Imperial College London

Professor Sir Tejinder Singh Virdee FRS

Faculty of Natural SciencesDepartment of Physics

Professor of Physics
 
 
 
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Contact

 

t.virdee Website

 
 
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Location

 

506Blackett LaboratorySouth Kensington Campus

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Summary

 

Publications

Publication Type
Year
to

1150 results found

Sirunyan AM, Tumasyan A, Adam W, Ambrogi F, Bergauer T, Brandstetter J, Dragicevic M, Eroe J, Del Valle AE, Flechl M, Fruehwirth R, Jeitler M, Krammer N, Kraetschmer I, Liko D, Madlener T, Mikulec I, Rad N, Schieck J, Schoefbeck R, Spanring M, Spitzbart D, Waltenberger W, Wulz C-E, Zarucki M, Drugakov V, Mossolov V, Gonzalez JS, Darwish MR, De Wolf EA, Di Croce D, Janssen X, Lelek A, Pieters M, Sfar HR, Van Haevermaet H, Van Mechelen P, Van Putte S, Van Remortel N, Blekman F, Bols ES, Chhibra SS, D'Hondt J, De Clercq J, Lontkovskyi D, Lowette S, Marchesini I, Moortgat S, Python Q, Skovpen K, Tavernier S, Van Doninck W, Van Mulders P, Burns D, Beghin D, Bilin B, Brun H, Clerbaux B, De Lentdecker G, Delannoy H, Dorney B, Favart L, Grebenyuk A, Kalsi AK, Popov A, Postiau N, Starling E, Thomas L, Vander Velde C, Vanlaer P, Vannerom D, Fang W, Gao X, Cornelis T, Dobur D, Khvastunov I, Niedziela M, Roskas C, Trocino D, Tytgat M, Verbeke W, Vermassen B, Vit M, Bondu O, Bruno G, Caputo C, David P, Delaere C, Delcourt M, Giammanco A, Lemaitre V, Prisciandaro J, Saggio A, Marono MV, Vischia P, Zobec J, Alves FL, Alves GA, Correia Silva G, Hensel C, Moraes A, Rebello Teles P, Belchior Batista Das Chagas E, Carvalho W, Chinellato J, Coelho E, Da Costa EM, Da Silveira GG, De Jesus Damiao D, De Oliveira Martins C, Fonseca De Souza S, Huertas Guativa LM, Malbouisson H, Martins J, Matos Figueiredo D, Medina Jaime M, Melo De Almeida M, Mora Herrera C, Mundim L, Nogima H, Prado Da Silva WL, Sanchez Rosas LJ, Santoro A, Sznajder A, Thiel M, Tonelli Manganote EJ, Torres Da Silva De Araujo F, Vilela Pereira A, Bernardes CA, Calligaris L, Fernandez Perez Tomei TR, Novaes SF, Padula S, Gregores EM, Lemos DS, Mercadante PG, Aleksandrov A, Antchev G, Hadjiiska R, Iaydjiev P, Misheva M, Rodozov M, Shopova M, Sultanov G, Bonchev M, Dimitrov A, Ivanov T, Litov L, Pavlov B, Petkov P, Yuan L, Ahmad M, Hu Z, Wang Y, Dozen C, Chen GM, Chen HS, Chen M, Jiang CH, Leggat D, Liao H, Liu Z, Spiezia Aet al., 2020, Measurement of CKM matrix elements in single top quark t-channel production in proton-proton collisions at root s=13 TeV, Physics Letters B: Nuclear Physics and Particle Physics, Vol: 808, Pages: 1-31, ISSN: 0370-2693

The first direct, model-independent measurement is presented of the modulus of the Cabibbo–Kobayashi–Maskawa (CKM) matrix elements |Vtb|, |Vtd|, and |Vts|, in final states enriched in single top quark t-channel events. The analysis uses proton-proton collision data from the LHC, collected during 2016 by the CMS experiment, at a centre-of-mass energy of 13 TeV, corresponding to an integrated luminosity of 35.9 fb−1. Processes directly sensitive to these matrix elements are considered at both the production and decay vertices of the top quark. In the standard model hypothesis of CKM unitarity, a lower limit of |Vtb| >0.970 is measured at the 95% confidence level. Several theories beyond the standard model are considered, and by releasing all constraints among the involved parameters, the values |Vtb| =0.988 ±0.024, and |Vtd|2+|Vts|2=0.06 ±0.06, where the uncertainties include both statistical and systematic components, are measured.

Journal article

Sirunyan AM, Tumasyan A, Adam W, Ambrogi F, Asilar E, Bergauer T, Brandstetter J, Dragicevic M, Ero J, Del Valle AE, Flechl M, Fruhwirth R, Ghete VM, Hrubec J, Jeitler M, Krammer N, Kratschmer I, Liko D, Madlener T, Mikulec I, Rad N, Rohringer H, Schieck J, Schofbeck R, Spanring M, Spitzbart D, Taurok A, Waltenberger W, Wittmann J, Wulz C-E, Zarucki M, Chekhovsky V, Mossolov V, Gonzalez JS, De Wolf EA, Di Croce D, Janssen X, Lauwers J, Pieters M, Van Haevermaet H, Van Mechelen P, Van Remortel N, Abu Zeid S, Blekman F, D'Hondt J, De Bruyn I, De Clercq J, Deroover K, Flouris G, Lontkovskyi D, Lowette S, Marchesini I, Moortgat S, Moreels L, Python Q, Skovpen K, Tavernier S, Van Doninck W, Van Mulders P, Van Parijs I, Beghin D, Bilin B, Brun H, Clerbaux B, De Lentdecker G, Delannoy H, Dorney B, Fasanella G, Favart L, Goldouzian R, Grebenyuk A, Kalsi AK, Lenzi T, Luetic J, Postiau N, Starling E, Thomas L, Vander Velde C, Vanlaer P, Vannerom D, Wang Q, Cornelis T, Dobur D, Fagot A, Gul M, Khvastunov I, Poyraz D, Roskas C, Trocino D, Tytgat M, Verbeke W, Vermassen B, Vit M, Zaganidis N, Bakhshiansohi H, Bondu O, Brochet S, Bruno G, Caputo C, David P, Delaere C, Delcourt M, Giammanco A, Krintiras G, Lemaitre V, Magitteri A, Mertens A, Musich M, Piotrzkowski K, Saggio A, Vidal Marono M, Wertz S, Zobec J, Alves FL, Alves GA, Martins Junior MC, Correia Silva G, Hensel C, Moraes A, Pol ME, Teles PR, Batista Das Chagas EB, Carvalho W, Chinellato J, Coelho E, Da Costa EM, Da Silveira GG, Damiao DDJ, Martins CDO, De Souza SF, Malbouisson H, Figueiredo DM, De Almeida MM, Herrera CM, Mundim L, Nogima H, Da Silva WLP, Rosas LJS, Santoro A, Sznajder A, Thiel M, Tonelli Manganote EJ, Da Silva De Araujo FT, Pereira AV, Ahuja S, Bernardes CA, Calligaris L, Perez Tomei TRF, Gregores EM, Mercadante PG, Novaes SF, Padula SS, Aleksandrov A, Hadjiiska R, Iaydjiev P, Marinov A, Misheva M, Rodozov M, Shopova M, Sultanov G, Dimitrov A, Litov L, Pavlov B, Petkov P, Fang W, Gao X, Yuan L, Wang Yet al., 2020, Studies of Charm Quark Diffusion inside Jets Using Pb-Pb and <i>pp</i> Collisions at √<i>s</i><sub>NN</sub>=5.02 TeV, Publisher: AMER PHYSICAL SOC

Working paper

Sirunyan AM, Tumasyan A, Adam W, Ambrogi F, Bergauer T, Brandstetter J, Dragicevic M, Eroe J, Del Valle AE, Flechl M, Fruehwirth R, Jeitler M, Krammer N, Kraetschmer I, Liko D, Madlener T, Mikulec I, Rad N, Schieck J, Schoefbeck R, Spanring M, Spitzbart D, Waltenberger W, Wulz C-E, Zarucki M, Drugakov V, Mossolov V, Gonzalez JS, Darwish MR, De Wolf EA, Di Croce D, Janssen X, Lelek A, Pieters M, Sfar HR, Van Haevermaet H, Van Mechelen P, Van Putte S, Van Remortel N, Blekman F, Bols ES, Chhibra SS, D'Hondt J, De Clercq J, Lontkovskyi D, Lowette S, Marchesini I, Moortgat S, Python Q, Skovpen K, Tavernier S, Van Doninck W, Van Mulders P, Beghin D, Bilin B, Brun H, Clerbaux B, De Lentdecker G, Delannoy H, Dorney B, Favart L, Grebenyuk A, Kalsi AK, Popov A, Postiau N, Starling E, Thomas L, Vander Velde C, Vanlaer P, Vannerom D, Cornelis T, Dobur D, Khvastunov I, Niedziela M, Roskas C, Tytgat M, Verbeke W, Vermassen B, Vit M, Bondu O, Bruno G, Caputo C, David P, Delaere C, Delcourt M, Giammanco A, Lemaitre V, Prisciandaro J, Saggio A, Marono MV, Vischia P, Zobec J, Alves FL, Alves GA, Silva GC, Hensel C, Moraes A, Teles PR, Chagas EBBS, Carvalho W, Chinellato J, Coelho E, Costa EM, Silveira GG, Damiao DDJ, Martins CDO, De Souza SF, Guativa LMH, Malbouisson H, Martins J, Figueiredo DM, Jaime MM, De Almeida MM, Herrera CM, Mundim L, Nogima H, Da Silva WLP, Rosas LJS, Santoro A, Sznajder A, Thiel M, Manganote EJT, De Araujo FTS, Pereira AV, Bernardes CA, Calligaris L, Tomei TRFP, Gregores EM, Lemos DS, Mercadante PG, Novaes SF, Padula SS, Aleksandrov A, Antchev G, Hadjiiska R, Iaydjiev P, Misheva M, Rodozov M, Shopova M, Sultanov G, Bonchev M, Dimitrov A, Ivanov T, Litov L, Pavlov B, Petkov P, Fang W, Gao X, Yuan L, Chen GM, Chen HS, Chen M, Jiang CH, Leggat D, Liao H, Liu Z, Spiezia A, Tao J, Yazgan E, Zhang H, Zhang S, Zhao J, Agapitos A, Ban Y, Chen G, Levin A, Li J, Li L, Li Q, Mao Y, Qian SJ, Wang D, Wang Q, Ahmad M, Hu Z, Wang Y, Xiao M, Avila C, Cabrera A, Florez C, Heet al., 2020, Pileup mitigation at CMS in 13 TeV data, Journal of Instrumentation, Vol: 15, Pages: 1-58, ISSN: 1748-0221

With increasing instantaneous luminosity at the LHC come additional reconstruction challenges. At high luminosity, many collisions occur simultaneously within one proton-proton bunch crossing. The isolation of an interesting collision from the additional "pileup" collisions is needed for effective physics performance. In the CMS Collaboration, several techniques capable of mitigating the impact of these pileup collisions have been developed. Such methods include charged-hadron subtraction, pileup jet identification, isospin-based neutral particle "δβ" correction, and, most recently, pileup per particle identification. This paper surveys the performance of these techniques for jet and missing transverse momentum reconstruction, as well as muon isolation. The analysis makes use of data corresponding to 35.9 fb−1 collected with the CMS experiment in 2016 at a center-of-mass energy of 13 TeV. The performance of each algorithm is discussed for up to 70 simultaneous collisions per bunch crossing. Significant improvements are found in the identification of pileup jets, the jet energy, mass, and angular resolution, missing transverse momentum resolution, and muon isolation when using pileup per particle identification.

Journal article

Sirunyan AM, Tumasyan A, Adam W, Ambrogi F, Bergauer T, Dragicevic M, Ero J, Del Valle AE, Flechl M, Fruhwirth R, Jeitler M, Kratschmer I, Liko D, Madlener T, Mikulec I, Rad N, Schieck J, Schofbeck R, Spanring M, Waltenberger W, Wulz C-E, Zarucki M, Drugakov V, Mossolov V, Gonzalez JS, Darwish M, De Wolf E, Di Croce D, Janssen X, Kello T, Lelek A, Pieters M, Sfar HR, Van Haevermaet H, Van Mechelen P, Van Putte S, Van Remortel N, Blekman F, Bols ES, Chhibra SS, D'Hondt J, De Clercq J, Lontkovskyi D, Lowette S, Marchesini I, Moortgat S, Python Q, Tavernier S, Van Doninck W, Van Mulders P, Beghin D, Bilin B, Clerbaux B, De Lentdecker G, Delannoy H, Dorney B, Favart L, Kalsi AK, Moureaux L, Popov A, Postiau N, Starling E, Thomas L, Vander Velde C, Vanlaer P, Vannerom D, Cornelis T, Dobur D, Khvastunov I, Niedziela M, Roskas C, Skovpen K, Tytgat M, Verbeke W, Vermassen B, Vit M, Bruno G, Caputo C, David P, Delaere C, Delcourt M, Giammanco A, Lemaitre V, Prisciandaro J, Saggio A, Vischia P, Zobec J, Alves GA, Correia Silva G, Hensel C, Moraes A, Batista Das Chagas EB, Carvalho W, Chinellato J, Coelho E, Da Costa EM, Da Silveira GG, De Jesus Damiao D, De Oliveira Martins C, Fonseca De Souza S, Malbouisson H, Martins J, Matos Figueiredo D, Medina Jaime M, Melo De Almeida M, Mora Herrera C, Mundim L, Nogima H, Prado Da Silva WL, Rebello Teles P, Sanchez Rosas LJ, Santoro A, Sznajder A, Thiel M, Tonelli Manganote EJ, Da Silva De Araujo FT, Vilela Pereira A, Bernardes CA, Calligaris L, Fernandez Perez Tomei TR, Gregores EM, Lemos DS, Mercadante PG, Novaes SF, Padula SS, Aleksandrov A, Antchev G, Hadjiiska R, Iaydjiev P, Misheva M, Rodozov M, Shopova M, Sultanov G, Bonchev M, Dimitrov A, Ivanov T, Litov L, Pavlov B, Petkov P, Petrov A, Fang W, Gao X, Yuan L, Ahmad M, Hu Z, Wang Y, Chen GM, Chen HS, Chen M, Jiang CH, Leggat D, Liao H, Liu Z, Spiezia A, Tao J, Yazgan E, Zhang H, Zhang S, Zhao J, Agapitos A, Ban Y, Chen G, Levin A, Li J, Li L, Li Q, Mao Y, Qian SJ, Wang D, Wang Qet al., 2020, Search for a light pseudoscalar Higgs boson in the boosted mu mu tau tau final state in proton-proton collisions at root s=13 TeV, The Journal of High Energy Physics, Vol: 2020, Pages: 1-44, ISSN: 1029-8479

A search for a light pseudoscalar Higgs boson (a) decaying from the 125 GeV (or a heavier) scalar Higgs boson (H) is performed using the 2016 LHC proton-proton collision data at s√ = 13 TeV, corresponding to an integrated luminosity of 35.9 fb−1, collected by the CMS experiment. The analysis considers gluon fusion and vector boson fusion production of the H, followed by the decay H → aa → μμττ, and considers pseudoscalar masses in the range 3.6 < ma < 21 GeV. Because of the large mass difference between the H and the a bosons and the small masses of the a boson decay products, both the μμ and the ττ pairs have high Lorentz boost and are collimated. The ττ reconstruction efficiency is increased by modifying the standard technique for hadronic τ lepton decay reconstruction to account for a nearby muon. No significant signal is observed. Model-independent limits are set at 95% confidence level, as a function of ma, on the branching fraction (ℬ) for H → aa → μμττ, down to 1.5 (2.0) × 10−4 for mH = 125 (300) GeV. Model-dependent limits on ℬ(H → aa) are set within the context of two Higgs doublets plus singlet models, with the most stringent results obtained for Type-III models. These results extend current LHC searches for heavier a bosons that decay to resolved lepton pairs and provide the first such bounds for an H boson with a mass above 125 GeV.

Journal article

Sirunyan AM, Tumasyan A, Adam W, Ambrogi F, Bergauer T, Brandstetter J, Dragicevic M, Ero J, Del Valle AE, Flechl M, Fruhwirth R, Jeitler M, Krammer N, Kratschmer I, Liko D, Madlener T, Mikulec I, Rad N, Schieck J, Schofbeck R, Spanring M, Spitzbart D, Waltenberger W, Wulz C-E, Zarucki M, Drugakov V, Mossolov V, Gonzalez JS, Darwish MR, De Wolf EA, Di Croce D, Janssen X, Lelek A, Pieters M, Sfar HR, Van Haevermaet H, Van Mechelen P, Van Putte S, Van Remortel N, Blekman F, Bols ES, Chhibra SS, D'Hondt J, De Clercq J, Lontkovskyi D, Lowette S, Marchesini I, Moortgat S, Python Q, Skovpen K, Tavernier S, Van Doninck W, Van Mulders P, Beghin D, Bilin B, Brun H, Clerbaux B, De Lentdecker G, Delannoy H, Dorney B, Favart L, Grebenyuk A, Kalsi AK, Popov A, Postiau N, Starling E, Thomas L, Vander Velde C, Vanlaer P, Vannerom D, Cornelis T, Dobur D, Khvastunov I, Niedziela M, Roskas C, Tytgat M, Verbeke W, Vermassen B, Vit M, Bondu O, Bruno G, Caputo C, David P, Delaere C, Delcourt M, Giammanco A, Lemaitre V, Prisciandaro J, Saggio A, Marono MV, Vischia P, Zobec J, Alves FL, Alves GA, Silva GC, Hensel C, Moraes A, Teles PR, Chagas EBBS, Carvalho W, Chinellato J, Coelho E, Costa EM, Silveira GG, Damiao DDJ, Martins CDO, De Souza SF, Guativa LMH, Malbouisson H, Martins J, Figueiredo DM, Jaime MM, De Almeida MM, Herrera CM, Mundim L, Nogima H, Da Silva WLP, Rosas LJS, Santoro A, Sznajder A, Thiel M, Manganote EJT, De Araujo FTS, Pereira AV, Bernardes CA, Calligaris L, Tomei TRFP, Gregores EM, Lemos DS, Mercadante PG, Novaes SF, Padula SS, Aleksandrov A, Antchev G, Hadjiiska R, Iaydjiev P, Misheva M, Rodozov M, Shopova M, Sultanov G, Bonchev M, Dimitrov A, Ivanov T, Litov L, Pavlov B, Petkov P, Fang W, Gao X, Yuan L, Chen GM, Chen HS, Chen M, Jiang CH, Leggat D, Liao H, Liu Z, Spiezia A, Tao J, Yazgan E, Zhang H, Zhang S, Zhao J, Agapitos A, Ban Y, Chen G, Levin A, Li J, Li L, Li Q, Mao Y, Qian SJ, Wang D, Wang Q, Ahmad M, Hu Z, Wang Y, Xiao M, Avila C, Cabrera A, Florez C, Hernanet al., 2020, Measurement of the associated production of a Z boson with charm or bottom quark jets in proton-proton collisions at root s=13 TeV, Physical Review D: Particles, Fields, Gravitation and Cosmology, Vol: 102, Pages: 032007 – 1-032007 – 20, ISSN: 1550-2368

Ratios of cross sections, σ(Z+c  jets)/σ(Z+jets), σ(Z+b  jets)/σ(Z+jets), and σ(Z+c  jets)/σ(Z+b  jets) in the associated production of a Z boson with at least one charm or bottom quark jet are measured in proton-proton collisions at √s=13  TeV. The data sample, collected by the CMS experiment at the CERN LHC, corresponds to an integrated luminosity of 35.9  fb−1, with a fiducial volume of pT>30  GeV and |η|<2.4 for the jets, where pT and η represent transverse momentum and pseudorapidity, respectively. The Z boson candidates come from leptonic decays into electrons or muons with pT>25  GeV and |η|<2.4, and the dilepton mass satisfies 71<mZ<111  GeV. The measured values are σ(Z+c  jets)/σ(Z+jets)=0.102±0.002±0.009, σ(Z+b  jets)/σ(Z+jets)=0.0633±0.0004±0.0015, and σ(Z+c  jets)/σ(Z+b  jets)=1.62±0.03±0.15. Results on the inclusive and differential cross section ratios as functions of jet and Z boson transverse momentum are compared with predictions from leading and next-to-leading order perturbative quantum chromodynamics calculations. These are the first measurements of the cross section ratios at 13 TeV.

Journal article

Sirunyan AM, Tumasyan A, Adam W, Ambrogi F, Bergauer T, Dragicevic M, Erö J, Escalante Del Valle A, Flechl M, Frühwirth R, Jeitler M, Krammer N, Krätschmer I, Liko D, Madlener T, Mikulec I, Rad N, Schieck J, Schöfbeck R, Spanring M, Waltenberger W, Wulz C-E, Zarucki M, Drugakov V, Mossolov V, Suarez Gonzalez J, Darwish MR, De Wolf EA, Di Croce D, Janssen X, Lelek A, Pieters M, Rejeb Sfar H, Van Haevermaet H, Mechelen PV, Putte SV, Remortel NV, Blekman F, Bols ES, Chhibra SS, D'Hondt J, De Clercq J, Lontkovskyi D, Lowette S, Marchesini I, Moortgat S, Python Q, Tavernier S, Doninck WV, Mulders PV, Beghin D, Bilin B, Clerbaux B, De Lentdecker G, Delannoy H, Dorney B, Favart L, Grebenyuk A, Kalsi AK, Moureaux L, Popov A, Postiau N, Starling E, Thomas L, Vander Velde C, Vanlaer P, Vannerom D, Cornelis T, Dobur D, Khvastunov I, Niedziela M, Roskas C, Skovpen K, Tytgat M, Verbeke W, Vermassen B, Vit M, Bondu O, Bruno G, Caputo C, David P, Delaere C, Delcourt M, Giammanco A, Lemaitre V, Prisciandaro J, Saggio A, Vidal Marono M, Vischia P, Zobec J, Alves GA, Correia Silva G, Hensel C, Moraes A, Das Chagas EBB, Carvalho W, Chinellato J, Coelho E, Da Costa EM, Da Silveira GG, De Jesus Damiao D, De Oliveira Martins C, Fonseca De Souza S, Huertas Guativa LM, Malbouisson H, Martins J, Matos Figueiredo D, Medina Jaime M, Melo De Almeida M, Herrera CM, Mundim L, Nogima H, Prado Da Silva WL, Rebello Teles P, Sanchez Rosas LJ, Santoro A, Sznajder A, Thiel M, Tonelli Manganote EJ, Torres Da Silva De Araujo F, Vilela Pereira A, Bernardes CA, Calligaris L, Fernandez Perez Tomei TR, Gregores EM, Lemos DS, Mercadante PG, Novaes SF, Padula SS, Aleksandrov A, Antchev G, Hadjiiska R, Iaydjiev P, Misheva M, Rodozov M, Shopova M, Sultanov G, Bonchev M, Dimitrov A, Ivanov T, Litov L, Pavlov B, Petkov P, Petrov A, Fang W, Gao X, Yuan L, Ahmad M, Hu Z, Wang Y, Chen GM, Chen HS, Chen M, Jiang CH, Leggat D, Liao H, Liu Z, Spiezia A, Tao J, Yazgan E, Zhang H, Zhang S, Zhao J, Agapitos A, Ban Y, Chenet al., 2020, Search for physics beyond the standard model in events with jets and two same-sign or at least three charged leptons in proton-proton collisions at s =13 TeV, European Physical Journal C: Particles and Fields, Vol: 80, ISSN: 1124-1861

A data sample of events from proton-proton collisions with at least two jets, and two isolated same-sign or three or more charged leptons, is studied in a search for signatures of new physics phenomena. The data correspond to an integrated luminosity of 137 fb - 1 at a center-of-mass energy of 13 TeV , collected in 2016-2018 by the CMS experiment at the LHC. The search is performed using a total of 168 signal regions defined using several kinematic variables. The properties of the events are found to be consistent with the expectations from standard model processes. Exclusion limits at 95% confidence level are set on cross sections for the pair production of gluinos or squarks for various decay scenarios in the context of supersymmetric models conserving or violating R parity. The observed lower mass limits are as large as 2.1 TeV for gluinos and 0.9 TeV for top and bottom squarks. To facilitate reinterpretations, model-independent limits are provided in a set of simplified signal regions.

Journal article

Sirunyan AM, Tumasyan A, Adam W, Ambrogi F, Bergauer T, Dragicevic M, Ero J, Del Valle AE, Fruhwirth R, Jeitler M, Krammer N, Lechner L, Liko D, Madlener T, Mikulec I, Rad N, Schieck J, Schofbeck R, Spanring M, Templ S, Waltenberger W, Wulz C-E, Zarucki M, Chekhovsky V, Litomin A, Makarenko V, Gonzalez JS, Darwish MR, De Wolf EA, Di Croce D, Janssen X, Kello T, Lelek A, Pieters M, Sfar HR, Van Haevermaet H, Van Mechelen P, Van Putte S, Van Remortel N, Blekman F, Bols ES, Chhibra SS, D'Hondt J, De Clercq J, Lontkovskyi D, Lowette S, Marchesini I, Moortgat S, Python Q, Tavernier S, Van Doninck W, Van Mulders P, Beghin D, Bilin B, Clerbaux B, De Lentdecker G, Delannoy H, Dorney B, Favart L, Grebenyuk A, Kalsi AK, Makarenko I, Moureaux L, Petre L, Popov A, Postiau N, Starling E, Thomas L, Vander Velde C, Vanlaer P, Vannerom D, Wezenbeek L, Cornelis T, Dobur D, Khvastunov I, Niedziela M, Roskas C, Skovpen K, Tytgat M, Verbeke W, Vermassen B, Vit M, Bruno G, Bury F, Caputo C, David P, Delaere C, Delcourt M, Donertas IS, Giammanco A, Lemaitre V, Prisciandaro J, Saggio A, Taliercio A, Teklishyn M, Vischia P, Wuyckens S, Zobec J, Alves GA, Silva GC, Hensel C, Moraes A, Alda Junior WL, Das Chagas EBB, Carvalho W, Chinellato J, Coelho E, Da Costa EM, Da Silveira GG, Damiao DDJ, De Souza SF, Malbouisson H, Martins J, Figueiredo DM, Jaime MM, De Almeida MM, Herrera CM, Mundim L, Nogima H, Teles PR, Rosas LJS, Santoro A, Do Amaral SMS, Sznajder A, Thiel M, Manganote EJT, De Araujo FTDS, Pereira AV, Bernardes CA, Calligaris L, Tomei TRFP, Gregores EM, Lemos DS, Mercadante PG, Novaes SF, Padula SS, Aleksandrov A, Antchev G, Atanasov I, Hadjiiska R, Iaydjiev P, Misheva M, Rodozov M, Shopova M, Sultanov G, Bonchev M, Dimitrov A, Ivanov T, Litov L, Pavlov B, Petkov P, Petrov A, Fang W, Guo Q, Wang H, Yuan L, Ahmad M, Hu Z, Wang Y, Chapon E, Chen GM, Chen HS, Chen M, Jiang CH, Leggat D, Liao H, Liu Z, Sharma R, Spiezia A, Tao J, Wang J, Zhang H, Zhang S, Zhao J, Agapitos A, Ban Y, Chenet al., 2020, Search for resonant pair production of Higgs bosons in the bbZZ channel in proton-proton collisions at root s=13 TeV, Physical Review D: Particles, Fields, Gravitation and Cosmology, Vol: 102, Pages: 032003 – 1-032003 – 26, ISSN: 1550-2368

A search for the production of a narrow-width resonance decaying into a pair of Higgs bosons decaying into the bbZZ channel is presented. The analysis is based on data collected with the CMS detector during 2016, in proton-proton collisions at the LHC, corresponding to an integrated luminosity of 35.9  fb−1. The final states considered are the ones where one of the Z bosons decays into a pair of muons or electrons, and the other Z boson decays to either a pair of quarks or a pair of neutrinos. Upper limits at 95% confidence level are placed on the production of narrow-width spin-0 or spin-2 particles decaying to a pair of Higgs bosons, in models with and without an extended Higgs sector. For a resonance mass range between 260 and 1000 GeV, limits on the production cross section times branching fraction of a spin-0 and spin-2 resonance range from 0.1 to 5.0 pb and 0.1 to 3.6 pb, respectively. These results set limits in parameter space in bulk Randall-Sundrum radion, Kaluza-Klein excitation of the graviton, and next-to-minimal two-Higgs doublet models (N2HDMs). For specific choices of parameters the N2HDM can be excluded in a mass range between 360 and 620 GeV for a resonance decaying to two Higgs bosons. This is the first search for Higgs boson resonant pair production in the bbZZ channel.

Journal article

Aad G, Abbott B, Abbott DC, Abud AA, Abeling K, Abhayasinghe DK, Abidi SH, AbouZeid OS, Abraham NL, Abramowicz H, Abreu H, Abulaiti Y, Acharya BS, Achkar B, Adam L, Bourdarios CA, Adamczyk L, Adamek L, Adelman J, Adersberger M, Adiguzel A, Adorni S, Adye T, Affolder AA, Afik Y, Agapopoulou C, Agaras MN, Aggarwal A, Agheorghiesei C, Aguilar-Saavedra JA, Ahmad A, Ahmadov F, Ahmed WS, Ai X, Aielli G, Akatsuka S, Akesson TPA, Akilli E, Akimov A, Al Khoury K, Alberghi GL, Albert J, Verzini MJA, Alderweireldt S, Aleksa M, Aleksandrov IN, Alexa C, Alexopoulos T, Alfonsi A, Alfonsi F, Alhroob M, Ali B, Ali S, Aliev M, Alimonti G, Allaire C, Allbrooke BMM, Allen BW, Allport PP, Aloisio A, Alonso F, Alpigiani C, Alshehri AA, Camelia EA, Alvarez Estevez M, Alviggi MG, Amaral Coutinho Y, Ambler A, Ambroz L, Amelung C, Amidei D, Amor Dos Santos SP, Amoroso S, Amrouche CS, An F, Anastopoulos C, Andari N, Andeen T, Anders CF, Anders JK, Andrean SY, Andreazza A, Andrei V, Anelli CR, Angelidakis S, Angerami A, Anisenkov A, Annovi A, Antel C, Anthony MT, Antipov E, Antonelli M, Antrim DJA, Anulli F, Aoki M, Aparisi Pozo JA, Aparo MA, Aperio Bella L, Araujo Ferraz V, Araujo Pereira R, Arcangeletti C, Arce ATH, Arduh FA, Arguin J-F, Argyropoulos S, Arling J-H, Armbruster AJ, Armstrong A, Arnaez O, Arnold H, Tame ZPA, Artoni G, Artz S, Asai S, Asawatavonvanich T, Asbah N, Asimakopoulou EM, Asquith L, Assahsah J, Assamagan K, Astalos R, Atkin RJ, Atkinson M, Atlay NB, Atmani H, Augsten K, Avolio G, Ayoub MK, Azuelos G, Bachacou H, Bachas K, Backes M, Backman F, Bagnaia P, Bahmani M, Bahrasemani H, Bailey AJ, Bailey VR, Baines JT, Bakalis C, Baker OK, Bakker PJ, Gupta DB, Balaji S, Baldin EM, Balek P, Balli F, Balunas WK, Balz J, Banas E, Bandieramonte M, Bandyopadhyay A, Banerjee S, Barak L, Barbe WM, Barberio EL, Barberis D, Barbero M, Barbour G, Barillari T, Barisits M-S, Barkeloo J, Barklow T, Barnea R, Barnett BM, Barnett RM, Barnovska-Blenessy Z, Baroncelli A, Barone G, Barr AJ, Baret al., 2020, Combination of the W boson polarization measurements in top quark decays using ATLAS and CMS data at root s=8 TeV, The Journal of High Energy Physics, Vol: 2020, Pages: 1-67, ISSN: 1029-8479

The combination of measurements of the W boson polarization in top quark decays performed by the ATLAS and CMS collaborations is presented. The measurements are based on proton-proton collision data produced at the LHC at a centre-of-mass energy of 8 TeV, and corresponding to an integrated luminosity of about 20 fb−1 for each experiment. The measurements used events containing one lepton and having different jet multiplicities in the final state. The results are quoted as fractions of W bosons with longitudinal (F0), left-handed (FL), or right-handed (FR) polarizations. The resulting combined measurements of the polarization fractions are F0 = 0.693 ± 0.014 and FL = 0.315 ± 0.011. The fraction FR is calculated from the unitarity constraint to be FR = −0.008 ± 0.007. These results are in agreement with the standard model predictions at next-to-next-to-leading order in perturbative quantum chromodynamics and represent an improvement in precision of 25 (29)% for F0 (FL) with respect to the most precise single measurement. A limit on anomalous right-handed vector (VR), and left- and right-handed tensor (gL, gR) tWb couplings is set while fixing all others to their standard model values. The allowed regions are [−0.11, 0.16] for VR, [−0.08, 0.05] for gL, and [−0.04, 0.02] for gR, at 95% confidence level. Limits on the corresponding Wilson coefficients are also derived.

Journal article

Sirunyan AM, Tumasyan A, Adam W, Ambrogi F, Bergauer T, Brandstetter J, Dragicevic M, Erö J, Del Valle AE, Flechl M, Frühwirth R, Jeitler M, Krammer N, Krätschmer I, Liko D, Madlener T, Mikulec I, Rad N, Schieck J, Schöfbeck R, Spanring M, Spitzbart D, Waltenberger W, Wittmann J, Wulz C-E, Zarucki M, Drugakov V, Mossolov V, Gonzalez JS, Darwish MR, De Wolf EA, Di Croce D, Janssen X, Lauwers J, Lelek A, Pieters M, Sfar HR, Van Haevermaet H, Van Mechelen P, Van Putte S, Van Remortel N, Blekman F, Bols ES, Chhibra SS, DHondt J, De Clercq J, Lontkovskyi D, Lowette S, Marchesini I, Moortgat S, Moreels L, Python Q, Skovpen K, Tavernier S, Van Doninck W, Van Mulders P, Van Parijs I, Beghin D, Bilin B, Brun H, Clerbaux B, De Lentdecker G, Delannoy H, Dorney B, Favart L, Grebenyuk A, Kalsi AK, Luetic J, Popov A, Postiau N, Starling E, Thomas L, Velde CV, Vanlaer P, Vannerom D, Wang Q, Cornelis T, Dobur D, Khvastunov I, Roskas C, Trocino D, Tytgat M, Verbeke W, Vermassen B, Vit M, Zaganidis N, Bondu O, Bruno G, Caputo C, David P, Delaere C, Delcourt M, Giammanco A, Krintiras G, Lemaitre V, Magitteri A, Piotrzkowski K, Prisciandaro J, Saggio A, Marono MV, Vischia P, Zobec J, Alves FL, Alves GA, Silva GC, Hensel C, Moraes A, Teles PR, Chagas EBBD, Carvalho W, Chinellato J, Coelho E, Costa EMD, Silveira GGD, Damiao DDJ, Martins CDO, De Souza SF, Guativa LMH, Malbouisson H, Martins J, Figueiredo DM, Jaime MM, De Almeida MM, Herrera CM, Mundim L, Nogima H, Da Silva WLP, Rosas LJS, Santoro A, Sznajder A, Thiel M, Manganote EJT, De Araujo FTDS, Pereira AV, Ahuja S, Bernardes CA, Calligaris L, Tomei TRFP, Gregores EM, Lemos DS, Mercadante PG, Novaes SF, Padula SS, Aleksandrov A, Antchev G, Hadjiiska R, Iaydjiev P, Marinov A, Misheva M, Rodozov M, Shopova M, Sultanov G, Dimitrov A, Litov L, Pavlov B, Petkov P, Fang W, Gao X, Yuan L, Hu Z, Wang Y, Ahmad M, Chen GM, Chen HS, Chen M, Jiang CH, Leggat D, Liao H, Liu Z, Shaheen SM, Spiezia A, Tao J, Yazgan E, Zhang H, Zhang S, Zhao J, Agaet al., 2020, Study of central exclusive [Inline Equation not available] production in proton-proton collisions at √s=5.02 and 13TeV, The European Physical Journal C, Vol: 80, Pages: 1-28, ISSN: 1434-6044

Central exclusive and semiexclusive production of pairs is measured with the CMS detector in proton-proton collisions at the LHC at center-of-mass energies of 5.02 and 13TeV. The theoretical description of these nonperturbative processes, which have not yet been measured in detail at the LHC, poses a significant challenge to models. The two pions are measured and identified in the CMS silicon tracker based on specific energy loss, whereas the absence of other particles is ensured by calorimeter information. The total and differential cross sections of exclusive and semiexclusive central production are measured as functions of invariant mass, transverse momentum, and rapidity of the system in the fiducial region defined as transverse momentum and pseudorapidity . The production cross sections for the four resonant channels , , , and are extracted using a simple model. These results represent the first measurement of this process at the LHC collision energies of 5.02 and 13TeV.

Journal article

Sirunyan AM, Tumasyan A, Adam W, Ambrogi F, Bergauer T, Dragicevic M, Ero J, Del Valle AE, Flechl M, Fruhwirth R, Jeitler M, Krammer N, Kratschmer I, Liko D, Madlener T, Mikulec I, Rad N, Schieck J, Schofbeck R, Spanring M, Waltenberger W, Wulz C-E, Zarucki M, Drugakov V, Mossolov V, Gonzalez JS, Darwish M, De Wolf E, Di Croce D, Janssen X, Kello T, Lelek A, Pieters M, Sfar HR, Van Haevermaet H, Van Mechelen P, Van Putte S, Van Remortel N, Blekman F, Bols ES, Chhibra SS, D'Hondt J, De Clercq J, Lontkovskyi D, Lowette S, Marchesini I, Moortgat S, Python Q, Tavernier S, Van Doninck W, Van Mulders P, Beghin D, Bilin B, Clerbaux B, De Lentdecker G, Delannoy H, Dorney B, Favart L, Kalsi AK, Moureaux L, Popov A, Postiau N, Starling E, Thomas L, Vander Velde C, Vanlaer P, Vannerom D, Cornelis T, Dobur D, Khvastunov I, Niedziela M, Roskas C, Skovpen K, Tytgat M, Verbeke W, Vermassen B, Vit M, Bruno G, Caputo C, David P, Delaere C, Delcourt M, Giammanco A, Lemaitre V, Prisciandaro J, Saggio A, Vischia P, Zobec J, Alves GA, Correia Silva G, Hensel C, Moraes A, Batista Das Chagas EB, Carvalho W, Chinellato J, Coelho E, Da Costa EM, Da Silveira GG, De Jesus Damiao D, De Oliveira Martins C, Fonseca De Souza S, Malbouisson H, Martins J, Matos Figueiredo D, Medina Jaime M, Melo De Almeida M, Mora Herrera C, Mundim L, Nogima H, Prado Da Silva WL, Rebello Teles P, Sanchez Rosas LJ, Santoro A, Sznajder A, Thiel M, Tonelli Manganote EJ, Da Silva De Araujo FT, Vilela Pereira A, Bernardes CA, Calligaris L, Fernandez Perez Tomei TR, Gregores EM, Lemos DS, Mercadante PG, Novaes SF, Padula SS, Aleksandrov A, Antchev G, Hadjiiska R, Iaydjiev P, Misheva M, Rodozov M, Shopova M, Sultanov G, Bonchev M, Dimitrov A, Ivanov T, Litov L, Pavlov B, Petkov P, Petrov A, Fang W, Gao X, Yuan L, Ahmad M, Hu Z, Wang Y, Chen GM, Chen HS, Chen M, Jiang CH, Leggat D, Liao H, Liu Z, Spiezia A, Tao J, Yazgan E, Zhang H, Zhang S, Zhao J, Agapitos A, Ban Y, Chen G, Levin A, Li J, Li L, Li Q, Mao Y, Qian SJ, Wanget al., 2020, Measurements of (tt)over-barH production and the CP structure of the Yukawa interaction between the Higgs Boson and top quark in the diphoton decay channel, Physical Review Letters, Vol: 125, Pages: 061801 – 1-061801 – 18, ISSN: 0031-9007

The first observation of the t¯tH process in a single Higgs boson decay channel with the full reconstruction of the final state (H→γγ) is presented, with a significance of 6.6 standard deviations (σ). The CP structure of Higgs boson couplings to fermions is measured, resulting in an exclusion of the pure CP-odd structure of the top Yukawa coupling at 3.2σ. The measurements are based on a sample of proton-proton collisions at a center-of-mass energy √s=13  TeV collected by the CMS detector at the LHC, corresponding to an integrated luminosity of 137  fb−1. The cross section times branching fraction of the t¯tH process is measured to be σt¯tHBγγ=1.56+0.34−0.32  fb, which is compatible with the standard model prediction of 1.13+0.08−0.11  fb. The fractional contribution of the CP-odd component is measured to be fHttCP=0.00±0.33.

Journal article

Sirunyan AM, Tumasyan A, Adam W, Ambrogi F, Asilar E, Bergauer T, Brandstetter J, Dragicevic M, Ero J, Del Valle AE, Flechl M, Fruhwirth R, Ghete VM, Hrubec J, Jeitler M, Krammer N, Kratschmer I, Liko D, Madlener T, Mikulec I, Rad N, Rohringer H, Schieck J, Schofbeck R, Spanring M, Spitzbart D, Waltenberger W, Wittmann J, Wulz C-E, Zarucki M, Chekhovsky V, Mossolov V, Gonzalez JS, De Wolf EA, Di Croce D, Janssen X, Lauwers J, Lelek A, Pieters M, Van Haevermaet H, Van Mechelen P, Van Remortel N, Blekman F, D'Hondt J, De Clercq J, Deroover K, Flouris G, Lontkovskyi D, Lowette S, Marchesini I, Moortgat S, Moreels L, Python Q, Skovpen K, Tavernier S, Van Doninck W, Van Mulders P, Van Parijs I, Beghin D, Bilin B, Brun H, Clerbaux B, De Lentdecker G, Delannoy H, Dorney B, Fasanella G, Favart L, Grebenyuk A, Kalsi AK, Luetic J, Popov A, Postiau N, Starling E, Thomas L, Vander Velde C, Vanlaer P, Vannerom D, Wang Q, Cornelis T, Dobur D, Fagot A, Gul M, Khvastunov I, Roskas C, Trocino D, Tytgat M, Verbeke W, Vermassen B, Vit M, Zaganidis N, Bondu O, Bruno G, Caputo C, David P, Delaere C, Delcourt M, Giammanco A, Krintiras G, Lemaitre V, Magitteri A, Piotrzkowski K, Saggio A, Marono MV, Vischia P, Zobec J, Alves FL, Alves GA, Silva GC, Hensel C, Moraes A, Pol ME, Teles PR, Chagas EBBS, Carvalho W, Chinellato J, Coelho E, Costa EM, Silveira GG, Damiao DDJ, Martins CDO, De Souza SF, Guativa LMH, Malbouisson H, Figueiredo DM, De Almeida MM, Herrera CM, Mundim L, Nogima H, Silva WLP, Rosas LJS, Santoro A, Sznajder A, Thiel M, Manganote EJT, De Araujo FTS, Pereira AV, Ahuja S, Bernardes CA, Calligaris L, Tomei TRFP, Gregores EM, Mercadante PG, Novaes SF, Padula S, Aleksandrov A, Hadjiiska R, Iaydjiev P, Marinov A, Misheva M, Rodozov M, Shopova M, Sultanov G, Dimitrov A, Litov L, Pavlov B, Petkov P, Fang W, Gao X, Yuan L, Wang Y, Ahmad M, Bian JG, Chen GM, Chen HS, Chen M, Jiang CH, Leggat D, Liao H, Liu Z, Shaheen SM, Spiezia A, Tao J, Yazgan E, Zhang H, Zhang S, Zhao J, Ban Y, Chet al., 2020, Measurement of t(t)over-bar normalised multi-differential cross sections in pp collisions at √<i>s</i>=13 TeV, and simultaneous determination of the strong coupling strength, top quark pole mass, and parton distribution functions, Publisher: SPRINGER

Working paper

Sirunyan AM, Tumasyan A, Adam W, Ambrogi F, Bergauer T, Brandstetter J, Dragicevic M, Ero J, Del Valle AE, Flechl M, Fruhwirth R, Jeitler M, Krammer N, Kratschmer I, Liko D, Madlener T, Mikulec I, Rad N, Schieck J, Schofbeck R, Spanring M, Spitzbart D, Waltenberger W, Wulz C-E, Zarucki M, Drugakov V, Mossolov V, Gonzalez JS, Darwish MR, De Wolf EA, Di Croce D, Janssen X, Lelek A, Pieters M, Sfar HR, Van Haevermaet H, Van Mechelen P, Van Putte S, Van Remortel N, Blekman F, Bols ES, Chhibra SS, D'Hondt J, De Clercq J, Lontkovskyi D, Lowette S, Marchesini I, Moortgat S, Python Q, Skovpen K, Tavernier S, Van Doninck W, Van Mulders P, Burns D, Beghin D, Bilin B, Brun H, Clerbaux B, De Lentdecker G, Delannoy H, Dorney B, Favart L, Grebenyuk A, Kalsi AK, Popov A, Postiau N, Starling E, Thomas L, Vander Velde C, Vanlaer P, Vannerom D, Cornelis T, Dobur D, Khvastunov I, Niedziela M, Roskas C, Tytgat M, Verbeke W, Vermassen B, Vit M, Bondu O, Bruno G, Caputo C, David P, Delaere C, Delcourt M, Giammanco A, Lemaitre V, Prisciandaro J, Saggio A, Marono MV, Vischia P, Zobec J, Alves FL, Alves GA, Correia Silva G, Hensel C, Moraes A, Rebello Teles P, Batista Das Chagas EB, Carvalho W, Chinellato J, Coelho E, Da Costa EM, Da Silveira GG, De Jesus Damiao D, De Oliveira Martins C, Fonseca De Souza S, Huertas Guativa LM, Malbouisson H, Martins J, Matos Figueiredo D, Medina Jaime M, Melo De Almeida M, Mora Herrera C, Mundim L, Nogima H, Prado Silva WL, Sanchez Rosas LJ, Santoro A, Sznajder A, Thiel M, Tonelli Manganote EJ, Da Silva De Araujo FT, Vilela Pereira A, Bernardes CA, Calligaris L, Fernandez Perez Tomei TR, Novaes SF, Padula SS, Gregores EM, Mercadante PG, Aleksandrov A, Antchev G, Hadjiiska R, Iaydjiev P, Misheva M, Rodozov M, Shopova M, Sultanov G, Bonchev M, Dimitrov A, Ivanov T, Litov L, Pavlov B, Petkov P, Fang W, Gao X, Yuan L, Ahmad M, Hu Z, Wang Y, Chen GM, Chen HS, Chen M, Jiang CH, Leggat D, Liao H, Liu Z, Spiezia A, Tao J, Yazgan E, Zhang H, Zhang S, Zhao J, Agapitoet al., 2020, Search for charged Higgs bosons decaying into a top and a bottom quark in the all-jet final state of pp collisions at root s=13 TeV, The Journal of High Energy Physics, Vol: 2020, Pages: 1-48, ISSN: 1029-8479

A search for charged Higgs bosons (H±) decaying into a top and a bottom quark in the all-jet final state is presented. The analysis uses LHC proton-proton collision data recorded with the CMS detector in 2016 at s√ = 13 TeV, corresponding to an integrated luminosity of 35.9 fb−1. No significant excess is observed above the expected background. Model-independent upper limits at 95% confidence level are set on the product of the H± production cross section and branching fraction in two scenarios. For production in association with a top quark, limits of 21.3 to 0.007 pb are obtained for H± masses in the range of 0.2 to 3 TeV. Combining this with a search in leptonic final states results in improved limits of 9.25 to 0.005 pb. The complementary s-channel production of an H± is investigated in the mass range of 0.8 to 3 TeV and the corresponding upper limits are 4.5 to 0.023 pb. These results are interpreted using different minimal supersymmetric extensions of the standard model.

Journal article

Sirunyan AM, Tumasyan A, Adam W, Ambrogi F, Bergauer T, Dragicevic M, Ero J, Del Valle AE, Flechl M, Fruhwirth R, Jeitler M, Krammer N, Kratschmer I, Liko D, Madlener T, Mikulec I, Rad N, Schieck J, Schofbeck R, Spanring M, Spitzbart D, Waltenberger W, Wulz C-E, Zarucki M, Drugakov V, Mossolov V, Gonzalez JS, Darwish MR, De Wolf EA, Di Croce D, Janssen X, Lelek A, Pieters M, Sfar HR, Van Haevermaet H, Van Mechelen P, Van Putte S, Van Remortel N, Blekman F, Bols ES, Chhibra SS, D'Hondt J, De Clercq J, Lontkovskyi D, Lowette S, Marchesini I, Moortgat S, Python Q, Skovpen K, Tavernier S, Van Doninck W, Van Mulders P, Burns D, Beghin D, Bilin B, Clerbaux B, De Lentdecker G, Delannoy H, Dorney B, Favart L, Grebenyuk A, Kalsi AK, Popov A, Postiau N, Starling E, Thomas L, Vander Velde C, Vanlaer P, Vannerom D, Cornelis T, Dobur D, Khvastunov I, Niedziela M, Roskas C, Tytgat M, Verbeke W, Vermassen B, Vit M, Bondu O, Bruno G, Caputo C, David P, Delaere C, Delcourt M, Giammanco A, Lemaitre V, Prisciandaro J, Saggio A, Marono MV, Vischia P, Zobec J, Alves FL, Alves GA, Correia Silva G, Hensel C, Moraes A, Rebello Teles P, Batista Das Chagas EB, Carvalho W, Chinellato J, Coelho E, Da Costa EM, Da Silveira GG, De Jesus Damiao D, De Oliveira Martins C, Fonseca De Souza S, Huertas Guativa LM, Malbouisson H, Martins J, Matos Figueiredo D, Medina Jaime M, Melo De Almeida M, Mora Herrera C, Mundim L, Nogima H, Prado Da Silva WL, Sanchez Rosas LJ, Santoro A, Sznajder A, Thiel M, Tonelli Manganote EJ, Da Silva De Araujo FT, Vilela Pereira A, Bernardes CA, Calligaris L, Fernandez Perez Tomei TR, Gregoresb EM, Lemos DS, Mercadante PC, Novaes SF, Padula S, Aleksandrov A, Antchev G, Hadjiiska R, Iaydjiev P, Misheva M, Rodozov M, Shopova M, Sultanov G, Bonchev M, Dimitrov A, Ivanov T, Litov L, Pavlov B, Petkov P, Fang W, Gao X, Yuan L, Ahmad M, Hu Z, Wang Y, Chen GM, Chen HS, Chen M, Jiang CH, Leggat D, Liao H, Liu Z, Spiezia A, Tao J, Yazgan E, Zhang H, Zhang S, Zhao J, Agapitos A, Ban Yet al., 2020, Measurement of the cross section for t(t)over-bar production with additional jets and b jets in pp collisions at root s=13TeV, The Journal of High Energy Physics, Vol: 2020, Pages: 1-46, ISSN: 1029-8479

Measurements of the cross section for the production of top quark pairs in association with a pair of jets from bottom quarks (σtt¯bb¯¯¯) and in association with a pair of jets from quarks of any flavor or gluons (σtt¯jj) and their ratio are presented. The data were collected in proton-proton collisions at a center-of-mass energy of 13 TeV by the CMS experiment at the LHC in 2016 and correspond to an integrated luminosity of 35.9 fb−1. The measurements are performed in a fiducial phase space and extrapolated to the full phase space, separately for the dilepton and lepton+jets channels, where lepton corresponds to either an electron or a muon. The results of the measurements in the fiducial phase space for the dilepton and lepton+jets channels, respectively, are σtt¯jj = 2.36±0.02 (stat)±0.20 (syst) pb and 31.0±0.2 (stat)±2.9 (syst) pb, and for the cross section ratio 0.017 ± 0.001 (stat) ± 0.001 (syst) and 0.020 ± 0.001 (stat) ± 0.001 (syst). The values of σtt¯bb¯¯¯ are determined from the product of the σtt¯jj and the cross section ratio, obtaining, respectively, 0.040±0.002 (stat)±0.005 (syst) pb and 0.62±0.03 (stat)±0.07 (syst) pb. These measurements are the most precise to date and are consistent, within the uncertainties, with the standard model expectations obtained using a matrix element calculation at next-to-leading order in quantum chromodynamics matched to a parton shower.

Journal article

Sirunyan AM, Tumasyan A, Adam W, Ambrogi F, Asilar E, Bergauer T, Brandstetter J, Dragicevic M, Eroe J, Del Valle AE, Flechl M, Fruehwirth R, Ghete VM, Hrubec J, Jeitler M, Krammer N, Kraetschmer I, Liko D, Madlener T, Mikulec I, Rad N, Rohringer H, Schieck J, Schoefbeck R, Spanring M, Spitzbart D, Taurok A, Waltenberger W, Wittmann J, Wulz C-E, Zarucki M, Chekhovsky V, Mossolov V, Gonzalez JS, De Wolf EA, Di Croce D, Janssen X, Lauwers J, Pieters M, Van De Klundert M, Janssen X, Lauwers J, Pieters M, Van De Klundert M, Van Haevermaet H, Van Mechelen P, Van Remortel N, Abu Zeid S, Blekman F, D'Hondt J, De Bruyn I, De Clercq J, Deroover K, Flouris G, Lontkovskyi D, Lowette S, Marchesini I, Moortgat S, Moreels L, Python Q, Skovpen K, Tavernier S, Van Doninck W, Van Mulders P, Van Parijs I, Beghin D, Bilin B, Brun H, Clerbaux B, De Lentdecker G, Delannoy H, Dorney B, Fasanella G, Favart L, Goldouzian R, Grebenyuk A, Kalsi AK, Lenzi T, Luetic J, Postiau N, Starling E, Thomas L, Vander Velde C, Vanlaer P, Vannerom D, Wang Q, Cornelis T, Dobur D, Fagot A, Gul M, Khvastunov I, Poyraz D, Roskas C, Trocino D, Tytgat M, Verbeke W, Vermassen B, Vit M, Zaganidis N, Bakhshiansohi H, Bondu O, Brochet S, Bruno G, Caputo C, David P, Delaere C, Delcourt M, Francois B, Giammanco A, Krintiras G, Lemaitre V, Magitteri A, Mertens A, Musich M, Piotrzkowski K, Saggio A, Marono MV, Wertz S, Zobec J, Alves FL, Alves GA, Martins Junior MC, Correia Silva G, Hensel C, Moraes A, Pol ME, Rebello Teles P, Belchior Batista Das Chagas E, Carvalho W, Chinellato J, Coelho E, Da Costa EM, Da Silveira GG, De Jesus Damiao D, De Oliveira Martins C, Fonseca De Souza S, Malbouisson H, Matos Figueiredo D, Melo De Almeida M, Mora Herrera C, Mundim L, Nogima H, Prado Da Silva WL, Sanchez Rosas LJ, Santoro A, Sznajder A, Thiel M, Tonelli Manganote EJ, Torres Da Silva De Araujo F, Vilela Pereira A, Ahuja S, Bernardes CA, Calligaris L, Fernandez Perez Tomei TR, Gregores EM, Mercadante PG, Novaes SF, Padula SS Ret al., 2020, Measurement of quark- and gluon-like jet fractions using jet charge in PbPb and pp collisions at 5.02 TeV, The Journal of High Energy Physics, Vol: 2020, Pages: 1-42, ISSN: 1029-8479

The momentum-weighted sum of the electric charges of particles inside a jet, known as jet charge, is sensitive to the electric charge of the particle initiating the parton shower. This paper presents jet charge distributions in sNN−−−√ = 5.02 TeV lead-lead (PbPb) and proton-proton (pp) collisions recorded with the CMS detector at the LHC. These data correspond to integrated luminosities of 404 μb−1 and 27.4 pb−1 for PbPb and pp collisions, respectively. Leveraging the sensitivity of the jet charge to fundamental differences in the electric charges of quarks and gluons, the jet charge distributions from simulated events are used as templates to extract the quark- and gluon-like jet fractions from data. The modification of these jet fractions is examined by comparing pp and PbPb data as a function of the overlap of the colliding Pb nuclei (centrality). This measurement tests the color charge dependence of jet energy loss due to interactions with the quark-gluon plasma. No significant modification between different centrality classes and with respect to pp results is observed in the extracted quark- and gluon-like jet fractions.

Journal article

Sirunyan AM, Tumasyan A, Adam W, Ambrogi F, Bergauer T, Dragicevic M, Eroe J, Del Valle AE, Flechl M, Fruehwirth R, Jeitler M, Krammer N, Kraetschmer I, Liko D, Madlener T, Mikulec I, Rad N, Schieck J, Schoefbeck R, Spanring M, Waltenberger W, Wulz C-E, Zarucki M, Drugakov V, Mossolov V, Gonzalez JS, Darwish MR, De Wolf EA, Di Croce D, Janssen X, Kello T, Lelek A, Pieters M, Sfar HR, Van Haevermaet H, Van Mechelen P, Van Putte S, Van Remortel N, Blekman F, Bols ES, Chhibra SS, D'Hondt J, De Clercq J, Lontkovskyi D, Lowette S, Marchesini I, Moortgat S, Python Q, Tavernier S, Van Doninck W, Van Mulders P, Burns D, Beghin D, Bilin B, Clerbaux B, De Lentdecker G, Delannoy H, Dorney B, Favart L, Grebenyuk A, Kalsi AK, Moureaux L, Popov A, Postiau N, Starling E, Thomas L, Vander Velde C, Vanlaer P, Vannerom D, Fang W, Gao X, Cornelis T, Dobur D, Khvastunov I, Niedziela M, Roskas C, Skovpen K, Tytgat M, Verbeke W, Vermassen B, Vit M, Bruno G, Caputo C, David P, Delaere C, Delcourt M, Giammanco A, Lemaitre V, Prisciandaro J, Saggio A, Vischia P, Zobec J, Alves GA, Correia Silva G, Hensel C, Moraes A, Belchior Batista Das Chagas E, Carvalho W, Chinellato J, Coelho E, Da Costa EM, Da Silveira GG, De Jesus Damiao D, De Oliveira Martins C, Fonseca De Souza S, Malbouisson H, Martins J, Matos Figueiredo D, Medina Jaime M, Melo De Almeida M, Mora Herrera C, Mundim L, Nogima H, Prado Da Silva WL, Rebello Teles P, Sanchez Rosas LJ, Santoro A, Sznajder A, Thiel M, Tonelli Manganote EJ, Torres Da Silva De Araujo F, Vilela Pereira A, Bernardes CA, Calligaris L, Fernandez Perez Tomei TR, Novaes SF, Padula S, Gregores EM, Mercadante PG, Aleksandrov A, Antchev G, Hadjiiska R, Iaydjiev P, Misheva M, Rodozov M, Shopova M, Sultanov G, Bonchev M, Dimitrov A, Ivanov T, Litov L, Pavlov B, Petkov P, Petrov A, Yuan L, Ahmad M, Hu Z, Wang Y, Dozen C, Chen GM, Chen HS, Chen M, Jiang CH, Leggat D, Liao H, Liu Z, Spiezia A, Tao J, Yazgan E, Zhang H, Zhang S, Zhao J, Agapitos A, Ban Y, Chen G, Levin Aet al., 2020, The production of isolated photons in PbPb and pp collisions at root s(NN)=5.02 TeV, The Journal of High Energy Physics, Vol: 2020, Pages: 1-39, ISSN: 1029-8479

The transverse energy (EγT) spectra of photons isolated from other particles are measured using proton-proton (pp) and lead-lead (PbPb) collisions at the LHC at sNN−−−√ = 5.02 TeV with integrated luminosities of 27.4 pb−1 and 404 μb−1 for pp and PbPb data, respectively. The results are presented for photons with 25 <EγT< 200 GeV in the pseudorapidity range |η| < 1.44, and for different centrality intervals for PbPb collisions. Photon production in PbPb collisions is consistent with that in pp collisions scaled by the number of binary nucleon-nucleon collisions, demonstrating that photons do not interact with the quark-gluon plasma. Therefore, isolated photons can provide information about the initial energy of the associated parton in photon+jet measurements. The results are compared with predictions from the next-to-leading-order jetphox generator for different parton distribution functions (PDFs) and nuclear PDFs (nPDFs). The comparisons can help to constrain the nPDFs global fits.

Journal article

Sirunyan AM, Tumasyan A, Adam W, Ambrogi F, Bergauer T, Dragicevic M, Ero J, Del Valle AE, Flechl M, Fruhwirth R, Jeitler M, Kratschmer I, Liko D, Madlener T, Mikulec I, Rad N, Schieck J, Schofbeck R, Spanring M, Waltenberger W, Wulz C-E, Zarucki M, Drugakov V, Mossolov V, Gonzalez JS, Darwish M, De Wolf E, Di Croce D, Janssen X, Kello T, Lelek A, Pieters M, Sfar HR, Van Haevermaet H, Van Mechelen P, Van Putte S, Van Remortel N, Blekman F, Bols ES, Chhibra SS, D'Hondt J, De Clercq J, Lontkovskyi D, Lowette S, Marchesini I, Moortgat S, Python Q, Tavernier S, Van Doninck W, Van Mulders P, Beghin D, Bilin B, Clerbaux B, De Lentdecker G, Delannoy H, Dorney B, Favart L, Kalsi AK, Moureaux L, Popov A, Postiau N, Starling E, Thomas L, Vander Velde C, Vanlaer P, Vannerom D, Cornelis T, Dobur D, Khvastunov I, Niedziela M, Roskas C, Skovpen K, Tytgat M, Verbeke W, Vermassen B, Vit M, Bruno G, Caputo C, David P, Delaere C, Delcourt M, Giammanco A, Lemaitre V, Prisciandaro J, Saggio A, Vischia P, Zobec J, Alves GA, Correia Silva G, Hensel C, Moraes A, Batista Das Chagas EB, Carvalho W, Chinellato J, Coelho E, Da Costa EM, Da Silveira GG, De Jesus Damiao D, De Oliveira Martins C, Fonseca De Souza S, Malbouisson H, Martins J, Matos Figueiredo D, Medina Jaime M, Melo De Almeida M, Mora Herrera C, Mundim L, Nogima H, Prado Da Silva WL, Rebello Teles P, Sanchez Rosas LJ, Santoro A, Sznajder A, Thiel M, Tonelli Manganote EJ, Da Silva De Araujo FT, Vilela Pereira A, Bernardes CA, Calligaris L, Fernandez Perez Tomei TR, Gregores EM, Lemos DS, Mercadante PG, Novaes SF, Padula SS, Aleksandrov A, Antchev G, Hadjiiska R, Iaydjiev P, Misheva M, Rodozov M, Shopova M, Sultanov G, Bonchev M, Dimitrov A, Ivanov T, Litov L, Pavlov B, Petkov P, Petrov A, Fang W, Gao X, Yuan L, Ahmad M, Hu Z, Wang Y, Chen GM, Chen HS, Chen M, Jiang CH, Leggat D, Liao H, Liu Z, Spiezia A, Tao J, Yazgan E, Zhang H, Zhang S, Zhao J, Agapitos A, Ban Y, Chen G, Levin A, Li J, Li L, Li Q, Mao Y, Qian SJ, Wang D, Wang Qet al., 2020, Search for disappearing tracks in proton-proton collisions at root s=13 TeV, Physics Letters B: Nuclear Physics and Particle Physics, Vol: 806, Pages: 1-27, ISSN: 0370-2693

A search is presented for long-lived charged particles that decay within the volume of the silicon tracker of the CMS experiment. Such particles can produce events with an isolated track that is missing hits in the outermost layers of the silicon tracker, and is also associated with little energy deposited in the calorimeters and no hits in the muon detectors. The search for events with this “disappearing track” signature is performed in a sample of proton-proton collisions recorded by the CMS experiment at the LHC with a center-of-mass energy of 13 TeV, corresponding to an integrated luminosity of 101 fb−1recorded in 2017 and 2018. The observation of 48 events is consistent with the estimated background of 47.8+2.7−2.3(stat)±8.1 (syst) events. Upper limits are set on chargino production in the context of an anomaly-mediated supersymmetry breaking model for purely wino and higgsino neutralino scenarios. At 95% confidence level, the first constraint is placed on chargino masses in the higgsino case, excluding below 750 (175) GeV for a lifetime of 3 (0.05) ns. In the wino case, the results of this search are combined with a previous CMS search to produce a result representing the complete LHC data set recorded in 2015–2018, the most stringent constraints to date. At 95% confidence level, chargino masses in the wino case are excluded below 884 (474) GeV for a lifetime of 3 (0.2) ns.

Journal article

Sirunyan AM, Tumasyan A, Adam W, Ambrogi F, Bergauer T, Brandstetter J, Dragicevic M, Eroe J, Del Valle AE, Flechl M, Fruehwirth R, Jeitler M, Krammer N, Kraetschmer I, Liko D, Madlener T, Mikulec I, Rad N, Schieck J, Schoefbeck R, Spanring M, Spitzbart D, Waltenberger W, Wulz C-E, Zarucki M, Drugakov V, Mossolov V, Gonzalez JS, Darwish MR, De Wolf EA, Di Croce D, Janssen X, Lelek A, Pieters M, Sfar HR, Van Haevermaet H, Van Mechelen P, Van Putte S, Van Remortel N, Blekman F, Bols ES, Chhibra SS, D'Hondt J, De Clercq J, Lontkovskyi D, Lowette S, Marchesini I, Moortgat S, Python Q, Skovpen K, Tavernier S, Van Doninck W, Van Mulders P, Burns D, Beghin D, Bilin B, Brun H, Clerbaux B, De Lentdecker G, Delannoy H, Dorney B, Favart L, Grebenyuk A, Kalsi AK, Popov A, Postiau N, Starling E, Thomas L, Vander Velde C, Vanlaer P, Vannerom D, Fang W, Gao X, Cornelis T, Dobur D, Khvastunov I, Niedziela M, Roskas C, Trocino D, Tytgat M, Verbeke W, Vermassen B, Vit M, Bondu O, Bruno G, Caputo C, David P, Delaere C, Delcourt M, Giammanco A, Lemaitre V, Prisciandaro J, Saggio A, Marono MV, Vischia P, Zobec J, Alves FL, Alves GA, Correia Silva G, Hensel C, Moraes A, Rebello Teles P, Belchior Batista Das Chagas E, Carvalho W, Chinellato J, Coelho E, Da Costa EM, Da Silveira GG, De Jesus Damiao D, De Oliveira Martins C, Fonseca De Souza S, Huertas Guativa LM, Malbouisson H, Martins J, Matos Figueiredo D, Medina Jaime M, Melo De Almeida M, Mora Herrera C, Mundim L, Nogima H, Prado Da Silva WL, Sanchez Rosas LJ, Santoro A, Sznajder A, Thiel M, Tonelli Manganote EJ, Torres Da Silva De Araujo F, Vilela Pereira A, Bernardes CA, Calligaris L, Fernandez Perez Tomei TR, Novaes SF, Padula S, Gregores EM, Lemos DS, Mercadante PG, Aleksandrov A, Antchev G, Hadjiiska R, Iaydjiev P, Misheva M, Rodozov M, Shopova M, Sultanov G, Bonchev M, Dimitrov A, Ivanov T, Litov L, Pavlov B, Petkov P, Yuan L, Ahmad M, Hu Z, Wang Y, Dozen C, Chen GM, Chen HS, Chen M, Jiang CH, Leggat D, Liao H, Liu Z, Spiezia Aet al., 2020, Measurement of the top quark forward-backward production asymmetry and the anomalous chromoelectric and chromomagnetic moments in in pp collisions at root s=13 TeV, The Journal of High Energy Physics, Vol: 2020, Pages: 1-56, ISSN: 1029-8479

The parton-level top quark (t) forward-backward asymmetry and the anomalous chromoelectric (d^t) and chromomagnetic (μ^t) moments have been measured using LHC pp collisions at a center-of-mass energy of 13 TeV, collected in the CMS detector in a data sample corresponding to an integrated luminosity of 35.9 fb−1. The linearized variable A(1)FB is used to approximate the asymmetry. Candidate tt¯ events decaying to a muon or electron and jets in final states with low and high Lorentz boosts are selected and reconstructed using a fit of the kinematic distributions of the decay products to those expected for tt¯ final states. The values found for the parameters are A(1)FB=0.048+0.095−0.087(stat)+0.020−0.029(syst),μ^t=−0.024+0.013−0.009(stat)+0.016−0.011(syst), and a limit is placed on the magnitude of ∣∣d^t∣∣< 0.03 at 95% confidence level.

Journal article

Sirunyan AM, Tumasyan A, Adam W, Ambrogi F, Asilar E, Bergauer T, Brandstetter J, Dragicevic M, Eroe J, Del Valle AE, Flechl M, Fruehwirth R, Ghete VM, Hrubec J, Jeitler M, Krammer N, Kraetschmer I, Liko D, Madlener T, Mikulec I, Rad N, Rohringer H, Schieck J, Schoefbeck R, Spanring M, Spitzbart D, Taurok A, Waltenberger W, Wittmann J, Wulz C-E, Zarucki M, Chekhovsky V, Mossolov V, Gonzalez JS, De Wolf EA, Di Croce D, Janssen X, Lauwers J, Pieters M, Van De Klundert M, Janssen X, Lauwers J, Pieters M, Van De Klundert M, Van Haevermaet H, Van Mechelen P, Van Remortel N, Abu Zeid S, Blekman F, D'Hondt J, De Bruyn I, De Clercq J, Deroover K, Flouris G, Lontkovskyi D, Lowette S, Marchesini I, Moortgat S, Moreels L, Python Q, Skovpen K, Tavernier S, Van Doninck W, Van Mulders P, Van Parijs I, Beghin D, Bilin B, Brun H, Clerbaux B, De Lentdecker G, Delannoy H, Dorney B, Fasanella G, Favart L, Goldouzian R, Grebenyuk A, Kalsi AK, Lenzi T, Luetic J, Postiau N, Starling E, Thomas L, Vander Velde C, Vanlaer P, Vannerom D, Wang Q, Cornelis T, Dobur D, Fagot A, Gul M, Khvastunov I, Poyraz D, Roskas C, Trocino D, Tytgat M, Verbeke W, Vermassen B, Vit M, Zaganidis N, Bakhshiansohi H, Bondu O, Brochet S, Bruno G, Caputo C, David P, Delaere C, Delcourt M, Francois B, Giammanco A, Krintiras G, Lemaitre V, Magitteri A, Mertens A, Musich M, Piotrzkowski K, Saggio A, Marono MV, Wertz S, Zobec J, Alves FL, Alves GA, Martins Junior MC, Correia Silva G, Hensel C, Moraes A, Pol ME, Rebello Teles P, Belchior Batista Das Chagas E, Carvalho W, Chinellato J, Coelho E, Da Costa EM, Da Silveira GG, De Jesus Damiao D, De Oliveira Martins C, Fonseca De Souza S, Malbouisson H, Matos Figueiredo D, Melo De Almeida M, Mora Herrera C, Mundim L, Nogima H, Prado Da Silva WL, Sanchez Rosas LJ, Santoro A, Sznajder A, Thiel M, Tonelli Manganote EJ, Torres Da Silva De Araujo F, Vilela Pereira A, Ahuja S, Bernardes CA, Calligaris L, Fernandez Perez Tomei TR, Gregores EM, Mercadante PG, Novaes SF, Padula SS Ret al., 2020, Strange hadron production in pp and pPb collisions at root(NN)-N-s=5.02 TeV, Physical Review C: Nuclear Physics, Vol: 101, Pages: 064906 – 1-064906 – 21, ISSN: 0556-2813

The transverse momentum (pT) distributions of Λ, Ξ−, and Ω− baryons, their antiparticles, and K0S mesons are measured in proton-proton (pp) and proton-lead (pPb) collisions at a nucleon-nucleon center-of-mass energy of 5.02 TeV over a broad rapidity range. The data, corresponding to integrated luminosities of 40.2 nb−1 and 15.6 μb−1 for pp and pPb collisions, respectively, were collected by the CMS experiment. The nuclear modification factor RpPb, which is defined as the ratio of the particle yield in pPb collisions and a scaled pp reference, is measured for each particle. A strong dependence on particle species is observed in the pT range from 2 to 7 GeV, where RpPb for K0S is consistent with unity, while an enhancement ordered by strangeness content and/or particle mass is observed for the three baryons. In pPb collisions, the strange hadron production is asymmetric about the nucleon-nucleon center-of-mass rapidity. Enhancements, which depend on the particle type, are observed in the direction of the Pb beam. The results are compared with predictions from epos lhc, which includes parametrized radial flow. The model is in qualitative agreement with the RpPb data, but fails to describe the dependence on particle species in the yield asymmetries measured away from midrapidity in pPb collisions.

Journal article

Sirunyan AM, Tumasyan A, Adam W, Ambrogi F, Bergauer T, Brandstetter J, Dragicevic M, Erö J, Escalante Del Valle A, Flechl M, Frühwirth R, Jeitler M, Krammer N, Krätschmer I, Liko D, Madlener T, Mikulec I, Rad N, Schieck J, Schöfbeck R, Spanring M, Spitzbart D, Waltenberger W, Wulz C-E, Zarucki M, Drugakov V, Mossolov V, Suarez Gonzalez J, Darwish MR, De Wolf EA, Di Croce D, Janssen X, Lelek A, Pieters M, Rejeb Sfar H, Van Haevermaet H, Van Mechelen P, Van Putte S, Van Remortel N, Blekman F, Bols ES, Chhibra SS, D'Hondt J, De Clercq J, Lontkovskyi D, Lowette S, Marchesini I, Moortgat S, Moreels L, Python Q, Skovpen K, Tavernier S, Van Doninck W, Van Mulders P, Van Parijs I, Beghin D, Bilin B, Brun H, Clerbaux B, De Lentdecker G, Delannoy H, Dorney B, Favart L, Grebenyuk A, Kalsi AK, Popov A, Postiau N, Starling E, Thomas L, Vander Velde C, Vanlaer P, Vannerom D, Cornelis T, Dobur D, Khvastunov I, Niedziela M, Roskas C, Trocino D, Tytgat M, Verbeke W, Vermassen B, Vit M, Zaganidis N, Bondu O, Bruno G, Caputo C, David P, Delaere C, Delcourt M, Giammanco A, Lemaitre V, Magitteri A, Prisciandaro J, Saggio A, Vidal Marono M, Vischia P, Zobec J, Alves FL, Alves GA, Correia Silva G, Hensel C, Moraes A, Rebello Teles P, Belchior Batista Das Chagas E, Carvalho W, Chinellato J, Coelho E, Da Costa EM, Da Silveira GG, De Jesus Damiao D, De Oliveira Martins C, Fonseca De Souza S, Huertas Guativa LM, Malbouisson H, Martins J, Matos Figueiredo D, Medina Jaime M, Melo De Almeida M, Mora Herrera C, Mundim L, Nogima H, Prado Da Silva WL, Sanchez Rosas LJ, Santoro A, Sznajder A, Thiel M, Tonelli Manganote EJ, Torres Da Silva De Araujo F, Vilela Pereira A, Bernardes CA, Calligaris L, Fernandez Perez Tomei TR, Gregores EM, Lemos DS, Mercadante PG, Novaes SF, Padula SS, Aleksandrov A, Antchev G, Hadjiiska R, Iaydjiev P, Marinov A, Misheva M, Rodozov M, Shopova M, Sultanov G, Bonchev M, Dimitrov A, Ivanov T, Litov L, Pavlov B, Petkov P, Fang W, Gao X, Yuan L, Ahmad M, Chen GM, Chen HS, Chet al., 2020, Mixed higher-order anisotropic flow and nonlinear response coefficients of charged particles in PbPb collisions at s NN =2.76 and 5.02TeV, European Physical Journal C: Particles and Fields, Vol: 80, ISSN: 1124-1861

Anisotropies in the initial energy density distribution of the quark-gluon plasma created in high energy heavy ion collisions lead to anisotropies in the azimuthal distributions of the final-state particles known as collective anisotropic flow. Fourier harmonic decomposition is used to quantify these anisotropies. The higher-order harmonics can be induced by the same order anisotropies (linear response) or by the combined influence of several lower order anisotropies (nonlinear response) in the initial state. The mixed higher-order anisotropic flow and nonlinear response coefficients of charged particles are measured as functions of transverse momentum and centrality in PbPb collisions at nucleon-nucleon center-of-mass energies s NN = 2.76 and 5.02 TeV with the CMS detector. The results are compared with viscous hydrodynamic calculations using several different initial conditions, as well as microscopic transport model calculations. None of the models provides a simultaneous description of the mixed higher-order flow harmonics and nonlinear response coefficients.

Journal article

Sirunyan AM, Tumasyan A, Adam W, Ambrogi F, Bergauer T, Brandstetter J, Dragicevic M, Eroe J, Del Valle AE, Flechl M, Fruehwirth R, Jeitler M, Krammer N, Kraetschmer I, Liko D, Madlener T, Mikulec I, Rad N, Schieck J, Schoefbeck R, Spanring M, Spitzbart D, Waltenberger W, Wulz C-E, Zarucki M, Drugakov V, Mossolov V, Gonzalez JS, Darwish MR, De Wolf EA, Di Croce D, Janssen X, Lelek A, Pieters M, Sfar HR, Van Haevermaet H, Van Mechelen P, Van Putte S, Van Remortel N, Blekman F, Bols ES, Chhibra SS, D'Hondt J, De Clercq J, Lontkovskyi D, Lowette S, Marchesini I, Moortgat S, Python Q, Skovpen K, Tavernier S, Van Doninck W, Van Mulders P, Burns D, Beghin D, Bilin B, Brun H, Clerbaux B, De Lentdecker G, Delannoy H, Dorney B, Favart L, Grebenyuk A, Kalsi AK, Popov A, Postiau N, Starling E, Thomas L, Vander Velde C, Vanlaer P, Vannerom D, Fang W, Gao X, Cornelis T, Dobur D, Khvastunov I, Niedziela M, Roskas C, Trocino D, Tytgat M, Verbeke W, Vermassen B, Vit M, Bondu O, Bruno G, Caputo C, David P, Delaere C, Delcourt M, Giammanco A, Lemaitre V, Prisciandaro J, Saggio A, Marono MV, Vischia P, Zobec J, Alves FL, Alves GA, Correia Silva G, Hensel C, Moraes A, Rebello Teles P, Belchior Batista Das Chagas E, Carvalho W, Chinellato J, Coelho E, Da Costa EM, Da Silveira GG, De Jesus Damiao D, De Oliveira Martins C, Fonseca De Souza S, Huertas Guativa LM, Malbouisson H, Martins J, Matos Figueiredo D, Medina Jaime M, Melo De Almeida M, Mora Herrera C, Mundim L, Nogima H, Prado Da Silva WL, Sanchez Rosas LJ, Santoro A, Sznajder A, Thiel M, Tonelli Manganote EJ, Torres Da Silva De Araujo F, Vilela Pereira A, Bernardes CA, Calligaris L, Fernandez Perez Tomei TR, Novaes SF, Padula S, Gregores EM, Lemos DS, Mercadante PG, Aleksandrov A, Antchev G, Hadjiiska R, Iaydjiev P, Misheva M, Rodozov M, Shopova M, Sultanov G, Bonchev M, Dimitrov A, Ivanov T, Litov L, Pavlov B, Petkov P, Yuan L, Ahmad M, Hu Z, Wang Y, Dozen C, Chen GM, Chen HS, Chen M, Jiang CH, Leggat D, Liao H, Liu Z, Spiezia Aet al., 2020, A measurement of the Higgs boson mass in the diphoton decay channel, Physics Letters B: Nuclear Physics and Particle Physics, Vol: 805, Pages: 1-25, ISSN: 0370-2693

A measurement of the mass of the Higgs boson in the diphoton decay channel is presented. This analysis is based on 35.9 fb−1of proton-proton collision data collected during the 2016 LHC running period, with the CMS detector at a centre-of-mass energy of 13 TeV. A refined detector calibration and new analysis techniques have been used to improve the precision of this measurement. The Higgs boson mass is measured to be mH=125.78 ±0.26 GeV. This is combined with a measurement of mHalready performed in the H→ZZ→4 decay channel using the same data set, giving mH=125.46 ±0.16 GeV. This result, when further combined with an earlier measurement of mHusing data collected in 2011 and 2012 with the CMS detector, gives a value for the Higgs boson mass of mH=125.38 ±0.14 GeV. This is currently the most precise measurement of the mass of the Higgs boson.

Journal article

Sirunyan AM, Tumasyan A, Adam W, Ambrogi F, Bergauer T, Dragicevic M, Eroe J, Del Valle AE, Flechl M, Fruehwirth R, Jeitler M, Krammer N, Kraetschmer I, Liko D, Madlener T, Mikulec I, Rad N, Schieck J, Schoefbeck R, Spanring M, Spitzbart D, Waltenberger W, Wulz C-E, Zarucki M, Drugakov V, Mossolov V, Gonzalez JS, Darwish MR, De Wolf EA, Di Croce D, Janssen X, Lelek A, Pieters M, Sfar HR, Van Haevermaet H, Van Mechelen P, Van Putte S, Van Remortel N, Blekman F, Bols ES, Chhibra SS, D'Hondt J, De Clercq J, Lontkovskyi D, Lowette S, Marchesini I, Moortgat S, Python Q, Skovpen K, Tavernier S, Van Doninck W, Van Mulders P, Beghin D, Bilin B, Clerbaux B, De Lentdecker G, Delannoy H, Dorney B, Favart L, Grebenyuk A, Kalsi AK, Popov A, Postiau N, Starling E, Thomas L, Vander Velde C, Vanlaer P, Vannerom D, Cornelis T, Dobur D, Khvastunov I, Niedziela M, Roskas C, Tytgat M, Verbeke W, Vermassen B, Vit M, Bondu O, Bruno G, Caputo C, David P, Delaere C, Delcourt M, Giammanco A, Lemaitre V, Prisciandaro J, Saggio A, Marono MV, Vischia P, Zobec J, Alves FL, Alves GA, Correia Silva G, Hensel C, Moraes A, Rebello Teles P, Belchior Batista Das Chagas E, Carvalho W, Chinellato J, Coelho E, Da Costa EM, Da Silveira GG, De Jesus Damiao D, De Oliveira Martins C, Fonseca De Souza S, Huertas Guativa LM, Malbouisson H, Martins J, Matos Figueiredo D, Medina Jaime M, Melo De Almeida M, Mora Herrera C, Mundim L, Nogima H, Prado Da Silva WL, Sanchez Rosas LJ, Santoro A, Sznajder A, Thiel M, Tonelli Manganote EJ, Torres Da Silva De Araujo F, Vilela Pereira A, Bernardes CA, Calligaris L, Fernandez Perez Tomei TR, Gregores EM, Lemos DS, Mercadante PG, Novaes SF, Padula SS, Aleksandrov A, Antchev G, Hadjiiska R, Iaydjiev P, Misheva M, Rodozov M, Shopova M, Sultanov G, Bonchev M, Dimitrov A, Ivanov T, Litov L, Pavlov B, Petkov P, Fang W, Gao X, Yuan L, Ahmad M, Hu Z, Wang Y, Chen GM, Chen HS, Chen M, Jiang CH, Leggat D, Liao H, Liu Z, Spiezia A, Tao J, Yazgan E, Zhang H, Zhang S, Zhao J, Agapitoset al., 2020, Search for dijet resonances using events with three jets in proton-proton collisions at root s=13 TeV, PHYSICS LETTERS B, Vol: 805, Pages: 1-23, ISSN: 0370-2693

A search for a narrow resonance with a mass between 350 and 700 GeV, and decaying into a pair of jets, is performed using proton-proton collision events containing at least three jets. The data sample corresponds to an integrated luminosity of 18.3 fb−1 recorded at with the CMS detector. Data are collected with a technique known as “data scouting”, in which the events are reconstructed, selected, and recorded at a high rate in a compact form by the high-level trigger. The three-jet final state provides sensitivity to lower resonance masses than in previous searches using the data scouting technique. The spectrum of the dijet invariant mass, calculated from the two jets with the largest transverse momenta in the event, is used to search for a resonance. No significant excess over a smoothly falling background is found. Limits at 95% confidence level are set on the production cross section of a narrow dijet resonance and compared with the cross section of a vector dark matter mediator coupling to dark matter particles and quarks. Translating to a model where the narrow resonance interacts only with quarks, upper limits on this coupling range between 0.10 and 0.15, depending on the resonance mass. These results represent the most stringent upper limits in the mass range between 350 and 450 GeV obtained with a flavor-inclusive dijet resonance search.

Journal article

Sirunyan AM, Tumasyan A, Adam W, Ambrogi F, Bergauer T, Brandstetter J, Dragicevic M, Eroe J, Del Valle AE, Flechl M, Fruehwirth R, Jeitler M, Krammer N, Kraetschmer I, Liko D, Madlener T, Mikulec I, Rad N, Schieck J, Schoefbeck R, Spanring M, Spitzbart D, Waltenberger W, Wulz C-E, Zarucki M, Drugakov V, Mossolov V, Gonzalez JS, Darwish MR, De Wolf EA, Di Croce D, Janssen X, Lelek A, Pieters M, Sfar HR, Van Haevermaet H, Van Mechelen P, Van Putte S, Van Remortel N, Blekman F, Bols ES, Chhibra SS, D'Hondt J, De Clercq J, Lontkovskyi D, Lowette S, Marchesini I, Moortgat S, Python Q, Skovpen K, Tavernier S, Van Doninck W, Van Mulders P, Burns D, Beghin D, Bilin B, Brun H, Clerbaux B, De Lentdecker G, Delannoy H, Dorney B, Favart L, Grebenyuk A, Kalsi AK, Popov A, Postiau N, Starling E, Thomas L, Vander Velde C, Vanlaer P, Vannerom D, Fang W, Gao X, Cornelis T, Dobur D, Khvastunov I, Niedziela M, Roskas C, Trocino D, Tytgat M, Verbeke W, Vermassen B, Vit M, Bondu O, Bruno G, Caputo C, David P, Delaere C, Delcourt M, Giammanco A, Lemaitre V, Prisciandaro J, Saggio A, Marono MV, Vischia P, Zobec J, Alves FL, Alves GA, Correia Silva G, Hensel C, Moraes A, Rebello Teles P, Belchior Batista Das Chagas E, Carvalho W, Chinellato J, Coelho E, Da Costa EM, Da Silveira GG, De Jesus Damiao D, De Oliveira Martins C, Fonseca De Souza S, Huertas Guativa LM, Malbouisson H, Martins J, Matos Figueiredo D, Medina Jaime M, Melo De Almeida M, Mora Herrera C, Mundim L, Nogima H, Prado Da Silva WL, Sanchez Rosas LJ, Santoro A, Sznajder A, Thiel M, Tonelli Manganote EJ, Torres Da Silva De Araujo F, Vilela Pereira A, Bernardes CA, Calligaris L, Fernandez Perez Tomei TR, Novaes SF, Padula S, Gregores EM, Lemos DS, Mercadante PG, Aleksandrov A, Antchev G, Hadjiiska R, Iaydjiev P, Misheva M, Rodozov M, Shopova M, Sultanov G, Bonchev M, Dimitrov A, Ivanov T, Litov L, Pavlov B, Petkov P, Yuan L, Ahmad M, Hu Z, Wang Y, Dozen C, Chen GM, Chen HS, Chen M, Jiang CH, Leggat D, Liao H, Liu Z, Spiezia Aet al., 2020, Measurement of the cross section for electroweak production of a Z boson, a photon and two jets in proton-proton collisions at root s=13TeV and constraints on anomalous quartic couplings, The Journal of High Energy Physics, Vol: 2020, Pages: 1-42, ISSN: 1029-8479

A measurement is presented of the cross section for electroweak production of a Z boson and a photon in association with two jets (Zγjj) in proton-proton collisions. The Z boson candidates are selected through their decay into a pair of electrons or muons. The process of interest, electroweak Zγjj production, is isolated by selecting events with a large dijet mass and a large pseudorapidity gap between the two jets. The measurement is based on data collected at the CMS experiment at s√ = 13 TeV, corresponding to an integrated luminosity of 35.9 fb−1. The observed significance of the signal is 3.9 standard deviations, where a significance of 5.2 standard deviations is expected in the standard model. These results are combined with published results by CMS at s√ = 8 TeV, which leads to observed and expected respective significances of 4.7 and 5.5 standard deviations. From the 13 TeV data, a value is obtained for the signal strength of electroweak Zγjj production and bounds are given on quartic vector boson interactions in the framework of dimension-eight effective field theory operators.

Journal article

Sirunyan AM, Tumasyan A, Adam W, Ambrogi F, Asilar E, Bergauer T, Brandstetter J, Dragicevic M, Eroe J, Del Valle AE, Flechl M, Fruehwirth R, Ghete VM, Hrubec J, Jeitler M, Krammer N, Kraetschmer I, Liko D, Madlener T, Mikulec I, Rad N, Rohringer H, Schieck J, Schoefbeck R, Spanring M, Spitzbart D, Taurok A, Waltenberger W, Wittmann J, Wulz C-E, Zarucki M, Chekhovsky V, Mossolov V, Gonzalez JS, De Wolf EA, Di Croce D, Janssen X, Lauwers J, Pieters M, Van De Klundert M, Janssen X, Lauwers J, Pieters M, Van De Klundert M, Van Haevermaet H, Van Mechelen P, Van Remortel N, Abu Zeid S, Blekman F, D'Hondt J, De Bruyn I, De Clercq J, Deroover K, Flouris G, Lontkovskyi D, Lowette S, Marchesini I, Moortgat S, Moreels L, Python Q, Skovpen K, Tavernier S, Van Doninck W, Van Mulders P, Van Parijs I, Beghin D, Bilin B, Brun H, Clerbaux B, De Lentdecker G, Delannoy H, Dorney B, Fasanella G, Favart L, Goldouzian R, Grebenyuk A, Kalsi AK, Lenzi T, Luetic J, Postiau N, Starling E, Thomas L, Vander Velde C, Vanlaer P, Vannerom D, Wang Q, Cornelis T, Dobur D, Fagot A, Gul M, Khvastunov I, Poyraz D, Roskas C, Trocino D, Tytgat M, Verbeke W, Vermassen B, Vit M, Zaganidis N, Bakhshiansohi H, Bondu O, Brochet S, Bruno G, Caputo C, David P, Delaere C, Delcourt M, Francois B, Giammanco A, Krintiras G, Lemaitre V, Magitteri A, Mertens A, Musich M, Piotrzkowski K, Saggio A, Marono MV, Wertz S, Zobec J, Alves FL, Alves GA, Martins Junior MC, Correia Silva G, Hensel C, Moraes A, Pol ME, Rebello Teles P, Belchior Batista Das Chagas E, Carvalho W, Chinellato J, Coelho E, Da Costa EM, Da Silveira GG, De Jesus Damiao D, De Oliveira Martins C, Fonseca De Souza S, Malbouisson H, Matos Figueiredo D, Melo De Almeida M, Mora Herrera C, Mundim L, Nogima H, Prado Da Silva WL, Sanchez Rosas LJ, Santoro A, Sznajder A, Thiel M, Tonelli Manganote EJ, Torres Da Silva De Araujo F, Vilela Pereira A, Ahuja S, Bernardes CA, Calligaris L, Fernandez Perez Tomei TR, Gregores EM, Mercadante PG, Novaes SF, Padula SS Ret al., 2020, Measurements with silicon photomultipliers of dose-rate effects in the radiation damage of plastic scintillator tiles in the CMS hadron endcap calorimeter, Journal of Instrumentation, Vol: 15, Pages: 1-48, ISSN: 1748-0221

Measurements are presented of the reduction of signal output due to radiation damage for two types of plastic scintillator tiles used in the hadron endcap (HE) calorimeter of the CMS detector. The tiles were exposed to particles produced in proton-proton (pp) collisions at the CERN LHC with a center-of-mass energy of 13 TeV, corresponding to a delivered luminosity of 50 fb−1. The measurements are based on readout channels of the HE that were instrumented with silicon photomultipliers, and are derived using data from several sources: a laser calibration system, a movable radioactive source, as well as hadrons and muons produced in pp collisions. Results from several irradiation campaigns using 60Co sources are also discussed. The damage is presented as a function of dose rate. Within the range of these measurements, for a fixed dose the damage increases with decreasing dose rate.

Journal article

Sirunyan AM, Tumasyan A, Adam W, Ambrogi F, Bergauer T, Brandstetter J, Dragicevic M, Eroe J, Del Valle AE, Flechl M, Fruehwirth R, Jeitler M, Krammer N, Krtschmer I, Liko D, Madlener T, Mikulec I, Rad N, Schieck J, Schoefbeck R, Spanring M, Spitzbart D, Waltenberger W, Wulz C-E, Zarucki M, Drugakov V, Mossolov V, Gonzalez JS, Darwish MR, De Wolf EA, Di Croce D, Janssen X, Lelek A, Pieters M, Sfar HR, Van Haevermaet H, Van Mechelen P, Van Putte S, Van Remortel N, Blekman F, Bols ES, Chhibra SS, D'Hondt J, De Clercq J, Lontkovskyi D, Lowette S, Marchesini I, Moortgat S, Python Q, Skovpen K, Tavernier S, Van Doninck W, Van Mulders P, Beghin D, Bilin B, Brun H, Clerbaux B, De Lentdecker G, Delannoy H, Dorney B, Favart L, Grebenyuk A, Kalsi AK, Popov A, Postiau N, Starling E, Thomas L, Vander Velde C, Vanlaer P, Vannerom D, Cornelis T, Dobur D, Khvastunov I, Niedziela M, Roskas C, Trocino D, Tytgat M, Verbeke W, Vermassen B, Vit M, Bondu O, Bruno G, Caputo C, David P, Delaere C, Delcourt M, Giammanco A, Lemaitre V, Prisciandaro J, Saggio A, Marono MV, Vischia P, Zobec J, Alves FL, Alves GA, Correia Silva G, Hensel C, Moraes A, Rebello Teles P, Belchior Batista Das Chagas E, Carvalho W, Chinellato J, Coelho E, Da Costa EM, Da Silveira GG, De Jesus Damiao D, De Oliveira Martins C, Fonseca De Souza S, Huertas Guativa LM, Malbouisson H, Martins J, Matos Figueiredo D, Medina Jaime M, Melo De Almeida M, Mora Herrera C, Mundim L, Nogima H, Prado Da Silva WL, Sanchez Rosas LJ, Santoro A, Sznajder A, Thiel M, Tonelli Manganote EJ, Torres Da Silva De Araujo F, Vilela Pereira A, Bernardes CA, Calligaris L, Fernandez Perez Tomei TR, Gregores EM, Lemos DS, Mercadante PG, Novaes SF, Padula SS, Aleksandrov A, Antchev G, Hadjiiska R, Iaydjiev P, Misheva M, Rodozov M, Shopova M, Sultanov G, Bonchev M, Dimitrov A, Ivanov T, Litov L, Pavlov B, Petkov P, Fang W, Gao X, Yuan L, Ahmad M, Hu Z, Wang Y, Chen GM, Chen HS, Chen M, Jiang CH, Leggat D, Liao H, Liu Z, Spiezia A, Tao J, Yazgan E, Zhet al., 2020, Measurement of the jet mass distribution and top quark mass in hadronic decays of boosted top quarks in pp collisions at root s=13 TeV, Physical Review Letters, Vol: 124, Pages: 202001-1-202001-19, ISSN: 0031-9007

A measurement is reported of the jet mass distribution in hadronic decays of boosted top quarks produced in pp collisions at √s=13  TeV. The data were collected with the CMS detector at the LHC and correspond to an integrated luminosity of 35.9  fb−1. The measurement is performed in the lepton+jets channel of t¯t events, where the lepton is an electron or muon. The products of the hadronic top quark decay t→bW→bq¯q′ are reconstructed as a single jet with transverse momentum larger than 400 GeV. The t¯t cross section as a function of the jet mass is unfolded at the particle level and used to extract a value of the top quark mass of 172.6±2.5  GeV. A novel jet reconstruction technique is used for the first time at the LHC, which improves the precision by a factor of 3 relative to an earlier measurement. This highlights the potential of measurements using boosted top quarks, where the new technique will enable future precision measurements.

Journal article

Sirunyan AM, Tumasyan A, Adam W, Ambrogi F, Bergauer T, Brandstetter J, Dragicevic M, Eroe J, Del Valle AE, Flechl M, Fruehwirth R, Jeitler M, Krammer N, Kraetschmer I, Liko D, Madlener T, Mikulec I, Rad N, Schieck J, Schoefbeck R, Spanring M, Spitzbart D, Waltenberger W, Wittmann J, Wulz C-E, Zarucki M, Drugakov V, Mossolov V, Gonzalez JS, Darwish MR, De Wolf EA, Di Croce D, Janssen X, Lauwers J, Lelek A, Pieters M, Sfar HR, Van Haevermaet H, Van Mechelen P, Van Putte S, Van Remortel N, Blekman F, Bols ES, Chhibra SS, DHondt J, De Clercq J, Lontkovskyi D, Lowette S, Marchesini I, Moortgat S, Moreels L, Python Q, Skovpen K, Tavernier S, Van Doninck W, Van Mulders P, Van Parijs I, Beghin D, Bilin B, Brun H, Clerbaux B, De Lentdecker G, Delannoy H, Dorney B, Favart L, Grebenyuk A, Kalsi AK, Luetic J, Popov A, Postiau N, Starling E, Thomas L, Vander Velde C, Vanlaer P, Vannerom D, Wang Q, Cornelis T, Dobur D, Khvastunov I, Roskas C, Trocino D, Tytgat M, Verbeke W, Vermassen B, Vit M, Zaganidis N, Bondu O, Bruno G, Caputo C, David P, Delaere C, Delcourt M, Giammanco A, Krintiras G, Lemaitre V, Magitteri A, Piotrzkowski K, Prisciandaro J, Saggio A, Marono MV, Vischia P, Zobec J, Alves FL, Alves GA, Correia Silva G, Hensel C, Moraes A, Rebello Teles P, Belchior Batista Das Chagas E, Carvalho W, Chinellato J, Coelho E, Da Costa EM, Da Silveira GG, De Jesus Damiao D, De Oliveira Martins C, Fonseca De Souza S, Huertas Guativa LM, Malbouisson H, Martins J, Matos Figueiredo D, Medina Jaime M, Melo De Almeida M, Mora Herrera C, Mundim L, Nogima H, Prado Da Silva WL, Sanchez Rosas LJ, Santoro A, Sznajder A, Thiel M, Tonelli Manganote EJ, Torres Da Silva De Araujo F, Vilela Pereira A, Ahuja S, Bernardes CA, Calligaris L, Fernandez Perez Tomei TR, Gregores EM, Lemos DS, Mercadante PG, Novaes SF, Padula S, Aleksandrov A, Antchev G, Hadjiiska R, Iaydjiev P, Marinov A, Misheva M, Rodozov M, Shopova M, Sultanov G, Dimitrov A, Litov L, Pavlov B, Petkov P, Fang W, Gao X, Yuan L, Ahmad Met al., 2020, Search for an excited lepton that decays via a contact interaction to a lepton and two jets in proton-proton collisions at root s=13 TeV, The Journal of High Energy Physics, Vol: 2020, Pages: 1-40, ISSN: 1029-8479

Results are presented from a search for events containing an excited lepton (electron or muon) produced in association with an ordinary lepton of the same flavor and decaying to a lepton and two hadronic jets. Both the production and the decay of the excited leptons are assumed to occur via a contact interaction with a characteristic energy scale Λ. The branching fraction for the decay mode under study increases with the mass of the excited lepton and is the most sensitive channel for very heavy excited leptons. The analysis uses a sample of proton-proton collisions collected by the CMS experiment at the LHC at s√ = 13 TeV, corresponding to an integrated luminosity of 77.4 fb−1. The four-body invariant mass of the two lepton plus two jet system is used as the primary discriminating variable. No significant excess of events beyond the expectation for standard model processes is observed. Assuming that Λ is equal to the mass of the excited leptons, excited electrons and muons with masses below 5.6 and 5.7 TeV, respectively, are excluded at 95% confidence level. These are the best limits to date.

Journal article

Sirunyan AM, Tumasyan A, Adam W, Ambrogi F, Asilar E, Bergauer T, Brandstetter J, Dragicevic M, Eroe J, Del Valle AE, Flechl M, Fruehwirth R, Ghete VM, Hrubec J, Jeitler M, Krammer N, Kraetschmer I, Liko D, Madlener T, Mikulec I, Rad N, Rohringer H, Schieck J, Schoefbeck R, Spanring M, Spitzbart D, Taurok A, Waltenberger W, Wittmann J, Wulz C-E, Zarucki M, Chekhovsky V, Mossolov V, Gonzalez JS, De Wolf EA, Di Croce D, Janssen X, Lauwers J, Pieters M, Van De Klundert M, Janssen X, Lauwers J, Pieters M, Van De Klundert M, Van Haevermaet H, Van Mechelen P, Van Remortel N, Abu Zeid S, Blekman F, D'Hondt J, De Bruyn I, De Clercq J, Deroover K, Flouris G, Lontkovskyi D, Lowette S, Marchesini I, Moortgat S, Moreels L, Python Q, Skovpen K, Tavernier S, Van Doninck W, Van Mulders P, Van Parijs I, Beghin D, Bilin B, Brun H, Clerbaux B, De Lentdecker G, Delannoy H, Dorney B, Fasanella G, Favart L, Goldouzian R, Grebenyuk A, Kalsi AK, Lenzi T, Luetic J, Postiau N, Starling E, Thomas L, Vander Velde C, Vanlaer P, Vannerom D, Wang Q, Cornelis T, Dobur D, Fagot A, Gul M, Khvastunov I, Poyraz D, Roskas C, Trocino D, Tytgat M, Verbeke W, Vermassen B, Vit M, Zaganidis N, Bakhshiansohi H, Bondu O, Brochet S, Bruno G, Caputo C, David P, Delaere C, Delcourt M, Francois B, Giammanco A, Krintiras G, Lemaitre V, Magitteri A, Mertens A, Musich M, Piotrzkowski K, Saggio A, Marono MV, Wertz S, Zobec J, Alves FL, Alves GA, Martins Junior MC, Correia Silva G, Hensel C, Moraes A, Pol ME, Rebello Teles P, Belchior Batista Das Chagas E, Carvalho W, Chinellato J, Coelho E, Da Costa EM, Da Silveira GG, De Jesus Damiao D, De Oliveira Martins C, Fonseca De Souza S, Malbouisson H, Matos Figueiredo D, Melo De Almeida M, Mora Herrera C, Mundim L, Nogima H, Prado Da Silva WL, Sanchez Rosas LJ, Santoro A, Sznajder A, Thiel M, Tonelli Manganote EJ, Torres Da Silva De Araujo F, Vilela Pereira A, Ahuja S, Bernardes CA, Calligaris L, Fernandez Perez Tomei TR, Gregores EM, Mercadante PG, Novaes SF, Padula SS Ret al., 2020, Study of J/psi meson production inside jets in pp collisions at N root s=8 TeV The CM Collaboration, Physics Letters B: Nuclear Physics and Particle Physics, Vol: 804, Pages: 1-24, ISSN: 0370-2693

A study of the production of prompt J/ψ mesons contained in jets in proton-proton collisions at√s = 8 TeV is presented. The analysis is based on data corresponding to an integrated luminosity of19.1 fb−1 collected with the CMS detector at the LHC. For events with at least one observed jet, theangular separation between the J/ψ meson and the jet is used to test whether the J/ψ meson is partof the jet. The analysis shows that most prompt J/ψ mesons having energy above 15 GeV and rapidity|y| < 1 are contained in jets with pseudorapidity |ηjet| < 1. The differential distributions of the probabilityto have a J/ψ meson contained in a jet as a function of jet energy for a fixed J/ψ energy fraction arecompared to a theoretical model using the fragmenting jet function approach. The data agree best withfragmenting jet function calculations that use a long-distance matrix element parameter set in whichprompt J/ψ mesons are predicted to be unpolarized. This technique demonstrates a new way to testpredictions for prompt J/ψ production using nonrelativistic quantum chromodynamics.

Journal article

Sirunyan AM, Tumasyan A, Adam W, Ambrogi F, Bergauer T, Brandstetter J, Dragicevic M, Eroe J, Del Valle AE, Flechl M, Fruehwirth R, Jeitler M, Krammer N, Kraetschmer I, Liko D, Madlener T, Mikulec I, Rad N, Schieck J, Schoefbeck R, Spanring M, Spitzbart D, Waltenberger W, Wulz C-E, Zarucki M, Drugakov V, Mossolov V, Gonzalez JS, Darwish MR, De Wolf EA, Di Croce D, Janssen X, Lelek A, Pieters M, Sfar HR, Van Haevermaet H, Van Mechelen P, Van Putte S, Van Remortel N, Blekman F, Bols ES, Chhibra SS, De Clercq J, Lontkovskyi D, Lowette S, Marchesini I, Moortgat S, Python Q, Skovpen K, Tavernier S, Van Doninck W, Van Mulders P, Beghin D, Bilin B, Brun H, Clerbaux B, De Lentdecker G, Delannoy H, Dorney B, Favart L, Grebenyuk A, Kalsi AK, Popov A, Postiau N, Starling E, Thomas L, Vander Velde C, Vanlaer P, Vannerom D, Cornelis T, Dobur D, Khvastunov I, Niedziela M, Roskas C, Tytgat M, Verbeke W, Vermassen B, Vit M, Bondu O, Bruno G, Caputo C, David P, Delaere C, Delcourt M, Giammanco A, Lemaitre V, Prisciandaro J, Saggio A, Marono MV, Vischia P, Zobec J, Alves FL, Alves GA, Correia Silva G, Hensel C, Moraes A, Rebello Teles P, Belchior Batista Das Chagas E, Carvalho W, Chinellato J, Coelho E, Da Costa EM, Da Silveira GG, De Jesus Damiao D, De Oliveira Martins C, Fonseca De Souza S, Huertas Guativa LM, Malbouisson H, Martins J, Matos Figueiredo D, Medina Jaime M, Melo De Almeida M, Herrera CM, Mundim L, Nogima H, Prado Da Silva WL, Sanchez Rosas LJ, Santoro A, Sznajder A, Thiel M, Tonelli Manganote EJ, Torres Da Silva De Araujo F, Vilela Pereira A, Bernardes CA, Calligaris L, Fernandez Perez Tomei TR, Gregores EM, Lemos DS, Mercadante PG, Novaes SF, Padula SS, Aleksandrov A, Antchev G, Hadjiiska R, Iaydjiev P, Misheva M, Rodozov M, Shopova M, Sultanov G, Bonchev M, Dimitrov A, Ivanov T, Litov L, Pavlov B, Petkov P, Fang W, Gao X, Yuan L, Chen GM, Chen HS, Chen M, Jiang CH, Leggat D, Liao H, Liu Z, Spiezia A, Tao J, Yazgan E, Zhang H, Zhang S, Zhao J, Agapitos A, Ban Y, Chenet al., 2020, Search for direct top squark pair production in events with one lepton, jets, and missing transverse momentum at 13 TeV with the CMS experiment, The Journal of High Energy Physics, Vol: 2020, Pages: 1-50, ISSN: 1029-8479

A search for direct top squark pair production is presented. The search is based on proton-proton collision data at a center-of-mass energy of 13 TeV recorded by the CMS experiment at the LHC during 2016, 2017, and 2018, corresponding to an integrated luminosity of 137 fb−1. The search is carried out using events with a single isolated electron or muon, multiple jets, and large transverse momentum imbalance. The observed data are consistent with the expectations from standard model processes. Exclusions are set in the context of simplified top squark pair production models. Depending on the model, exclusion limits at 95% confidence level for top squark masses up to 1.2 TeV are set for a massless lightest supersymmetric particle, assumed to be the neutralino. For models with top squark masses of 1 TeV, neutralino masses up to 600 GeV are excluded.

Journal article

Sirunyan AM, Tumasyan A, Adam W, Ambrogi F, Asilar E, Bergauer T, Brandstetter J, Dragicevic M, Eroe J, Del Valle AE, Flechl M, Fruehwirth R, Ghete VM, Hrubec J, Jeitler M, Krammer N, Kraetschmer I, Liko D, Madlener T, Mikulec I, Rad N, Rohringer H, Schieck J, Schoefbeck R, Spanring M, Spitzbart D, Taurok A, Waltenberger W, Wittmann J, Wulz C-E, Zarucki M, Chekhovsky V, Mossolov V, Gonzalez JS, De Wolf EA, Di Croce D, Janssen X, Lauwers J, Pieters M, Van De Klundert M, Janssen X, Lauwers J, Pieters M, Van De Klundert M, Van Haevermaet H, Van Mechelen P, Van Remortel N, Abu Zeid S, Blekman F, D'Hondt J, De Bruyn I, De Clercq J, Deroover K, Flouris G, Lontkovskyi D, Lowette S, Marchesini I, Moortgat S, Moreels L, Python Q, Skovpen K, Tavernier S, Van Doninck W, Van Mulders P, Van Parijs I, Beghin D, Bilin B, Brun H, Clerbaux B, De Lentdecker G, Delannoy H, Dorney B, Fasanella G, Favart L, Goldouzian R, Grebenyuk A, Kalsi AK, Lenzi T, Luetic J, Postiau N, Starling E, Thomas L, Vander Velde C, Vanlaer P, Vannerom D, Wang Q, Cornelis T, Dobur D, Fagot A, Gul M, Khvastunov I, Poyraz D, Roskas C, Trocino D, Tytgat M, Verbeke W, Vermassen B, Vit M, Zaganidis N, Bakhshiansohi H, Bondu O, Brochet S, Bruno G, Caputo C, David P, Delaere C, Delcourt M, Francois B, Giammanco A, Krintiras G, Lemaitre V, Magitteri A, Mertens A, Musich M, Piotrzkowski K, Saggio A, Marono MV, Wertz S, Zobec J, Alves FL, Alves GA, Martins Junior MC, Correia Silva G, Hensel C, Moraes A, Pol ME, Rebello Teles P, Belchior Batista Das Chagas E, Carvalho W, Chinellato J, Coelho E, Da Costa EM, Da Silveira GG, De Jesus Damiao D, De Oliveira Martins C, Fonseca De Souza S, Malbouisson H, Matos Figueiredo D, Melo De Almeida M, Mora Herrera C, Mundim L, Nogima H, Prado Da Silva WL, Sanchez Rosas LJ, Santoro A, Sznajder A, Thiel M, Tonelli Manganote EJ, Torres Da Silva De Araujo F, Vilela Pereira A, Ahuja S, Bernardes CA, Calligaris L, Fernandez Perez Tomei TR, Gregores EM, Mercadante PG, Novaes SF, Padula SS Ret al., 2020, Search for high mass dijet resonances with a new background prediction method in proton-proton collisions at root s=13 TeV, The Journal of High Energy Physics, Vol: 2020, Pages: 1-45, ISSN: 1029-8479

A search for narrow and broad resonances with masses greater than 1.8 TeV decaying to a pair of jets is presented. The search uses proton-proton collision data at s√ = 13 TeV collected at the LHC, corresponding to an integrated luminosity of 137 fb−1. The background arising from standard model processes is predicted with the fit method used in previous publications and with a new method. The dijet invariant mass spectrum is well described by both data-driven methods, and no significant evidence for the production of new particles is observed. Model independent upper limits are reported on the production cross sections of narrow resonances, and broad resonances with widths up to 55% of the resonance mass. Limits are presented on the masses of narrow resonances from various models: string resonances, scalar diquarks, axigluons, colorons, excited quarks, color-octet scalars, W′ and Z′ bosons, Randall-Sundrum gravitons, and dark matter mediators. The limits on narrow resonances are improved by 200 to 800 GeV relative to those reported in previous CMS dijet resonance searches. The limits on dark matter mediators are presented as a function of the resonance mass and width, and on the associated coupling strength as a function of the mediator mass. These limits exclude at 95% confidence level a dark matter mediator with a mass of 1.8 TeV and width 1% of its mass or higher, up to one with a mass of 4.8 TeV and a width 45% of its mass or higher.

Journal article

Sirunyan AM, Tumasyan A, Adam W, Ambrogi F, Asilar E, Bergauer T, Brandstetter J, Dragicevic M, Eroe J, Del Valle AE, Flechl M, Fruehwirth R, Ghete VM, Hrubec J, Jeitler M, Krammer N, Kraetschmer I, Liko D, Madlener T, Mikulec I, Rad N, Rohringer H, Schieck J, Schoefbeck R, Spanring M, Spitzbart D, Taurok A, Waltenberger W, Wittmann J, Wulz C-E, Zarucki M, Chekhovsky V, Mossolov V, Gonzalez JS, De Wolf EA, Di Croce D, Janssen X, Lauwers J, Pieters M, Van De Klundert M, Janssen X, Lauwers J, Pieters M, Van De Klundert M, Van Haevermaet H, Van Mechelen P, Van Remortel N, Abu Zeid S, Blekman F, D'Hondt J, De Bruyn I, De Clercq J, Deroover K, Flouris G, Lontkovskyi D, Lowette S, Marchesini I, Moortgat S, Moreels L, Python Q, Skovpen K, Tavernier S, Van Doninck W, Van Mulders P, Van Parijs I, Beghin D, Bilin B, Brun H, Clerbaux B, De Lentdecker G, Delannoy H, Dorney B, Fasanella G, Favart L, Goldouzian R, Grebenyuk A, Kalsi AK, Lenzi T, Luetic J, Postiau N, Starling E, Thomas L, Vander Velde C, Vanlaer P, Vannerom D, Wang Q, Cornelis T, Dobur D, Fagot A, Gul M, Khvastunov I, Poyraz D, Roskas C, Trocino D, Tytgat M, Verbeke W, Vermassen B, Vit M, Zaganidis N, Bakhshiansohi H, Bondu O, Brochet S, Bruno G, Caputo C, David P, Delaere C, Delcourt M, Francois B, Giammanco A, Krintiras G, Lemaitre V, Magitteri A, Mertens A, Musich M, Piotrzkowski K, Saggio A, Marono MV, Wertz S, Zobec J, Alves FL, Alves GA, Martins Junior MC, Correia Silva G, Hensel C, Moraes A, Pol ME, Rebello Teles P, Belchior Batista Das Chagas E, Carvalho W, Chinellato J, Coelho E, Da Costa EM, Da Silveira GG, De Jesus Damiao D, De Oliveira Martins C, Fonseca De Souza S, Malbouisson H, Matos Figueiredo D, Melo De Almeida M, Mora Herrera C, Mundim L, Nogima H, Prado Da Silva WL, Sanchez Rosas LJ, Santoro A, Sznajder A, Thiel M, Tonelli Manganote EJ, Torres Da Silva De Araujo F, Vilela Pereira A, Ahuja S, Bernardes CA, Calligaris L, Fernandez Perez Tomei TR, Gregores EM, Mercadante PG, Novaes SF, Padula SS Ret al., 2020, Measurement of differential cross sections and charge ratios for t-channel single top quark production in proton-proton collisions at mml:msqrts mml:msqrt=13 mml:mspace width="0.166667em"mml:mspaceTe mml:mspace width="0.333333em"mml:mspace, European Physical Journal C: Particles and Fields, Vol: 80, Pages: 1-37, ISSN: 1124-1861

A measurement is presented of differential cross sections for t-channel single top quark and antiquark production in proton–proton collisions at a centre-of-mass energy of 13TeV by the CMS experiment at the LHC. From a data set corresponding to an integrated luminosity of 35.9fb−1, events containing one muon or electron and two or three jets are analysed. The cross section is measured as a function of the top quark transverse momentum (pT), rapidity, and polarisation angle, the charged lepton pT and rapidity, and the pT of the W boson from the top quark decay. In addition, the charge ratio is measured differentially as a function of the top quark, charged lepton, and W boson kinematic observables. The results are found to be in agreement with standard model predictions using various next-to-leading-order event generators and sets of parton distribution functions. Additionally, the spin asymmetry, sensitive to the top quark polarisation, is determined from the differential distribution of the polarisation angle at parton level to be 0.440±0.070, in agreement with the standard model prediction.

Journal article

Sirunyan AM, Tumasyan A, Adam W, Ambrogi F, Bergauer T, Brandstetter J, Dragicevic M, Eroe J, Del Valle AE, Flechl M, Fruehwirth R, Jeitler M, Krammer N, Kraetschmer I, Liko D, Madlener T, Mikulec I, Rad N, Schieck J, Schoefbeck R, Spanring M, Spitzbart D, Waltenberger W, Wulz C-E, Zarucki M, Chekhovsky V, Mossolov V, Gonzalez JS, Darwish MR, De Wolf EA, Di Croce D, Janssen X, Lelek A, Pieters M, Sfar HR, Van Haevermaet H, Van Mechelen P, Van Putte S, Van Remortel N, Blekman F, Bols ES, Chhibra SS, D'Hondt J, De Clercq J, Lontkovskyi D, Lowette S, Marchesini I, Moortgat S, Moreels L, Python Q, Skovpen K, Tavernier S, Van Doninck W, Van Mulders P, Van Parijs I, Beghin D, Bilin B, Brun H, Clerbaux B, De Lentdecker G, Delannoy H, Dorney B, Favart L, Grebenyuk A, Kalsi AK, Popov A, Postiau N, Starling E, Thomas L, Vander Velde C, Vanlaer P, Vannerom D, Cornelis T, Dobur D, Khvastunov I, Niedziela M, Roskas C, Tytgat M, Verbeke W, Vermassen B, Vit M, Zaganidis N, Bondu O, Bruno G, Caputo C, David P, Delaere C, Delcourt M, Giammanco A, Lemaitre V, Magitteri A, Prisciandaro J, Saggio A, Marono MV, Vischia P, Zobec J, Alves FL, Alves GA, Correia Silva G, Hensel C, Moraes A, Rebello Teles P, Belchior Batista das Chagas E, Carvalho W, Chinellato J, Coelho E, Da Costa EM, Da Silveira GG, De Jesus Damiao D, De Oliveira Martins C, Fonseca De Souza S, Huertas Guativa LM, Malbouisson H, Martins J, Matos Figueiredo D, Medina Jaime M, Melo De Almeida M, Mora Herrera C, Mundim L, Nogima H, Prado Da Silva WL, Sanchez Rosas LJ, Santoro A, Sznajder A, Thiel M, Tonelli Manganote EJ, Torres Da Silva De Araujo F, Vilela Pereira A, Bernardes CA, Calligaris L, Fernandez Perez Tomei TR, Gregores EM, Lemos DS, Mercadante PG, Novaes SF, Padula SS, Aleksandrov A, Antchev G, Hadjiiska R, Iaydjiev P, Misheva M, Rodozov M, Shopova M, Sultanov G, Bonchev M, Dimitrov A, Ivanov T, Litov L, Pavlov B, Petkov P, Fang W, Gao X, Yuan L, Chen GM, Chen HS, Chen M, Jiang CH, Leggat D, Liao H, Liu Z, Spiezia Aet al., 2020, Calibration of the CMS hadron calorimeters using proton-proton collision data at root s=13 TeV, Journal of Instrumentation, Vol: 15, Pages: 1-48, ISSN: 1748-0221

Methods are presented for calibrating the hadron calorimeter system of the CMS detector at the LHC. The hadron calorimeters of the CMS experiment are sampling calorimeters of brass and scintillator, and are in the form of one central detector and two endcaps. These calorimeters cover pseudorapidities |η| < 3 and are positioned inside the solenoidal magnet. An outer calorimeter, outside the magnet coil, covers |η| < 1.26, and a steel and quartz-fiber Cherenkov forward calorimeter extends the coverage to |η| < 5.19. The initial calibration of the calorimeters was based on results from test beams, augmented with the use of radioactive sources and lasers. The calibration was improved substantially using proton-proton collision data collected at √s = 7, 8, and 13 TeV, as well as cosmic ray muon data collected during the periods when the LHC beams were not present. The present calibration is performed using the 13 TeV data collected during 2016 corresponding to an integrated luminosity of 35.9 fb−1. The intercalibration of channels exploits the approximate uniformity of energy collection over the azimuthal angle. The absolute energy scale of the central and endcap calorimeters is set using isolated charged hadrons. The energy scale for the electromagnetic portion of the forward calorimeters is set using Z→ ee data. The energy scale of the outer calorimeters has been determined with test beam data and is confirmed through data with high transverse momentum jets. In this paper, we present the details of the calibration methods and accuracy.

Journal article

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