Imperial College London

Professor Yoshi Uchida

Faculty of Natural SciencesDepartment of Physics

Professor of Physics
 
 
 
//

Contact

 

+44 (0)20 7594 7821yoshi.uchida Website

 
 
//

Location

 

524Blackett LaboratorySouth Kensington Campus

//

Summary

 

Publications

Publication Type
Year
to

278 results found

Abe K, Adrich P, Aihara H, Akutsu R, Alekseev I, Ali A, Ameli F, Anghel I, Anthony LH, Antonova M, Araya A, Asaoka Y, Ashida Y, Aushev V, Ballester F, Bandac I, Barbi M, Barker GJ, Barr G, Batkiewicz-Kwasniak M, Bellato M, Berardi V, Bergevin M, Bernard L, Bernardini E, Berns L, Bhadra S, Bian J, Blanchet A, Blaszczyk FDM, Blondel A, Boiano A, Bolognesi S, Bonavera L, Booth N, Borjabad S, Boschi T, Bose D, Bozza C, Bravar A, Bravo-Berguno D, Bronner C, Brown L, Bubak A, Buchowicz A, Avanzini MB, Cafagna FS, Calabria NF, Calvo-Mozota JM, Cao S, Cartwright SL, Carroll A, Catanesi MG, Cebrian S, Chabera M, Chakraborty S, Checchia C, Choi JH, Choubey S, Cicerchia M, Coleman J, Collazuol G, Cook L, Cowan G, Cuen-Rochin S, Danilov M, Daz Lopez G, De la Fuente E, de Perio P, De Rosa G, Dealtry T, Densham CJ, Dergacheva A, Deshmukh N, Devi MM, Di Lodovico F, Di Meo P, Di Palma I, Doyle TA, Drakopoulou E, Drapier O, Dumarchez J, Dunne P, Dziewiecki M, Eklund L, El Hedri S, Ellis J, Emery S, Esmaili A, Esteve R, Evangelisti A, Feely M, Fedotov S, Feng J, Fernandez P, Fernandez-Martinez E, Ferrario P, Ferrazzi B, Feusels T, Finch A, Finley C, Fiorentini A, Fiorillo G, Fitton M, Frankiewicz K, Friend M, Fujii Y, Fukuda Y, Galinski G, Gao J, Garde C, Garfagnini A, Garode S, Gialanella L, Giganti C, Gomez-Cadenas JJ, Gonin M, Gonzalez-Nuevo J, Gorin A, Gornea R, Gousy-Leblanc V, Gramegna F, Grassi M, Grella G, Guigue M, Gumplinger P, Hadley DR, Harada M, Hartfiel B, Hartz M, Hassani S, Hastings NC, Hayato Y, Hernando-Morata JA, Herrero V, Hill J, Hiraide K, Hirota S, Holin A, Horiuchi S, Hoshina K, Hultqvist K, Iacob F, Ichikawa AK, Ibnsalih WI, Iijima T, Ikeda M, Inomoto M, Inoue K, Insler J, Ioannisian A, Ishida T, Ishidoshiro K, Ishino H, Ishitsuka M, Ito H, Ito S, Itow Y, Iwamoto K, Izmaylov A, Izumi N, Izumiyama S, Jakkapu M, Jamieson B, Jang H, Jang JS, Jenkins SJ, Jeon SH, Jiang M, Jo HS, Jonsson P, Joo KK, Kajita T, Kakuno H, Kameda J, Kano Y, Kalaczynski P, Karlen D, Kaset al., 2021, Supernova Model Discrimination with Hyper-Kamiokande, ASTROPHYSICAL JOURNAL, Vol: 916, ISSN: 0004-637X

Journal article

Abe K, Akhlaq N, Akutsu R, Ali A, Alt C, Andreopoulos C, Antonova M, Aoki S, Arihara T, Asada Y, Ashida Y, Atkin ET, Awataguchi Y, Barker GJ, Barr G, Barrow D, Batkiewicz-Kwasniak M, Beloshapkin A, Bench F, Berardi V, Berns L, Bhadra S, Blanchet A, Blondel A, Bolognesi S, Bonus T, Bourguille B, Boyd SB, Bravar A, Bravo Berguño D, Bronner C, Bron S, Bubak A, Buizza Avanzini M, Cao S, Cartwright SL, Catanesi MG, Cervera A, Chakrani J, Cherdack D, Christodoulou G, Cicerchia M, Coleman J, Collazuol G, Cook L, Coplowe D, Cudd A, De Rosa G, Dealtry T, Delogu CC, Dennis SR, Densham C, Dergacheva A, Di Lodovico F, Dolan S, Douqa D, Doyle TA, Dumarchez J, Dunne P, Eguchi A, Eklund L, Emery-Schrenk S, Ereditato A, Finch AJ, Fiorillo G, Francois C, Friend M, Fujii Y, Fukuda R, Fukuda Y, Fusshoeller K, Giganti C, Gonin M, Goodman EAG, Gorin A, Grassi M, Guigue M, Hadley DR, Hamacher-Baumann P, Harris DA, Hartz M, Hasegawa T, Hassani S, Hastings NC, Hayato Y, Hiramoto A, Hogan M, Holeczek J, Hong Van NT, Honjo T, Iacob F, Ichikawa AK, Ikeda M, Ishida T, Ishitsuka M, Iwamoto K, Izmaylov A, Izumi N, Jakkapu M, Jamieson B, Jenkins SJ, Jesús-Valls C, Jiang JJ, Jonsson P, Jung CK, Jurj PB, Kabirnezhad M, Kakuno H, Kameda J, Kasetti SP, Kataoka Y, Katayama Y, Katori T, Kearns E, Khabibullin M, Khotjantsev A, Kikawa T, Kikutani H, King S, Kisiel J, Kobata T, Kobayashi T, Koch L, Konaka A, Kormos LL, Koshio Y, Kostin A, Kowalik K, Kudenko Y, Kuribayashi S, Kurjata R, Kutter T, Kuze M, Labarga L, Lagoda J, Lamoureux M, Last D, Laveder M, Lawe M, Lin S-K, Litchfield RP, Liu SL, Longhin A, Ludovici L, Lu X, Lux T, Machado LN, Magaletti L, Mahn K, Malek M, Manly S, Maret L, Marino AD, Marti-Magro L, Maruyama T, Matsubara T, Matsushita K, Mauger C, Maurel A, Mavrokoridis K, Mazzucato E, McCauley N, McElwee J, McFarland KS, McGrew C, Mefodiev A, Megias GD, Mellet L, Mezzetto M, Minamino A, Mineev O, Mine S, Miura M, Molina Bueno L, Moriyama S, Mueller TA, Munford D, Munteanu L, Nagai Y, Nakadet al., 2021, First T2K measurement of transverse kinematic imbalance in the muon-neutrino charged-current single-π+ production channel containing at least one proton, Physical Review D, Vol: 103, Pages: 1-27, ISSN: 2470-0010

This paper reports the first T2K measurement of the transverse kinematic imbalance in the single-π+ production channel of neutrino interactions. We measure the differential cross sections in the muon-neutrino charged-current interaction on hydrocarbon with a single π+ and at least one proton in the final state, at the ND280 off axis near detector of the T2K experiment. The extracted cross sections are compared to the predictions from different neutrino-nucleus interaction event generators. Overall, the results show a preference for models that have a more realistic treatment of nuclear medium effects including the initial nuclear state and final-state interactions.

Journal article

Abe K, Akhlaq N, Akutsu R, Ali A, Alt C, Andreopoulos C, Antonova M, Aoki S, Arihara T, Asada Y, Ashida Y, Atkin ET, Awataguchi Y, Barker GJ, Barr G, Barrow D, Batkiewicz-Kwasniak M, Beloshapkin A, Bench F, Berardi V, Berns L, Bhadra S, Blanchet A, Blondel A, Bolognesi S, Bonus T, Bourguille B, Boyd SB, Bravar A, Bravo Berguño D, Bronner C, Bron S, Bubak A, Buizza Avanzini M, Cao S, Cartwright SL, Catanesi MG, Cervera A, Chakrani J, Cherdack D, Christodoulou G, Cicerchia M, Coleman J, Collazuol G, Cook L, Coplowe D, Cudd A, De Rosa G, Dealtry T, Delogu CC, Dennis SR, Densham C, Dergacheva A, Di Lodovico F, Dolan S, Douqa D, Doyle TA, Dumarchez J, Dunne P, Eguchi A, Eklund L, Emery-Schrenk S, Ereditato A, Finch AJ, Fiorillo G, Francois C, Friend M, Fujii Y, Fukuda R, Fukuda Y, Fusshoeller K, Giganti C, Gonin M, Goodman EAG, Gorin A, Grassi M, Guigue M, Hadley DR, Hamacher-Baumann P, Harris DA, Hartz M, Hasegawa T, Hassani S, Hastings NC, Hayato Y, Hiramoto A, Hogan M, Holeczek J, Hong Van NT, Honjo T, Iacob F, Ichikawa AK, Ikeda M, Ishida T, Ishitsuka M, Iwamoto K, Izmaylov A, Izumi N, Jakkapu M, Jamieson B, Jenkins SJ, Jesús-Valls C, Jiang JJ, Jonsson P, Jung CK, Jurj PB, Kabirnezhad M, Kakuno H, Kameda J, Kasetti SP, Kataoka Y, Katayama Y, Katori T, Kearns E, Khabibullin M, Khotjantsev A, Kikawa T, Kikutani H, King S, Kisiel J, Kobata T, Kobayashi T, Koch L, Konaka A, Kormos LL, Koshio Y, Kostin A, Kowalik K, Kudenko Y, Kuribayashi S, Kurjata R, Kutter T, Kuze M, Labarga L, Lagoda J, Lamoureux M, Last D, Laveder M, Lawe M, Lin S-K, Litchfield RP, Liu SL, Longhin A, Ludovici L, Lu X, Lux T, Machado LN, Magaletti L, Mahn K, Malek M, Manly S, Maret L, Marino AD, Marti-Magro L, Maruyama T, Matsubara T, Matsushita K, Mauger C, Maurel A, Mavrokoridis K, Mazzucato E, McCauley N, McElwee J, McFarland KS, McGrew C, Mefodiev A, Megias GD, Mellet L, Mezzetto M, Minamino A, Mineev O, Mine S, Miura M, Molina Bueno L, Moriyama S, Mueller TA, Munford D, Munteanu L, Nagai Y, Nakadet al., 2021, Improved constraints on neutrino mixing from the T2K experiment with 3.13×1021 protons on target, Physical Review D, Vol: 103, Pages: 1-59, ISSN: 2470-0010

The T2K experiment reports updated measurements of neutrino and antineutrino oscillations using both appearance and disappearance channels. This result comes from an exposure of 14.9(16.4)×1020 protons on target in neutrino (antineutrino) mode. Significant improvements have been made to the neutrino interaction model and far detector reconstruction. An extensive set of simulated data studies have also been performed to quantify the effect interaction model uncertainties have on the T2K oscillation parameter sensitivity. T2K performs multiple oscillation analyses that present both frequentist and Bayesian intervals for the Pontecorvo-Maki-Nakagawa-Sakata parameters. For fits including a constraint on sin2θ13 from reactor data and assuming normal mass ordering T2K measures sin2θ23=0.53+0.03−0.04 and Δm232=(2.45±0.07)×10−3  eV2 c−4. The Bayesian analyses show a weak preference for normal mass ordering (89% posterior probability) and the upper sin2θ23 octant (80% posterior probability), with a uniform prior probability assumed in both cases. The T2K data exclude CP conservation in neutrino oscillations at the 2σ level.

Journal article

Abe K, Akhlaq N, Akutsu R, Ali A, Alt C, Andreopoulos C, Anthony L, Antonova M, Aoki S, Ariga A, Arihara T, Asada Y, Ashida Y, Atkin ET, Awataguchi Y, Ban S, Barbi M, Barker GJ, Barr G, Barrow D, Barry C, Batkiewicz-Kwasniak M, Beloshapkin A, Bench F, Berardi V, Berkman S, Berns L, Bhadra S, Bienstock S, Blanchet A, Blondel A, Bolognesi S, Bonus T, Bourguille B, Boyd SB, Brailsford D, Bravar A, Berguno DB, Bronner C, Bron S, Bubak A, Avanzini MB, Calcutt J, Campbell T, Cao S, Cartwright SL, Catanesi MG, Cervera A, Chappell A, Checchia C, Cherdack D, Chikuma N, Christodoulou G, Cicerchia M, Coleman J, Collazuol G, Cook L, Coplowe D, Cudd A, Dabrowska A, De Rosa G, Dealtry T, Denner PF, Dennis SR, Densham C, Dergacheva A, Di Lodovico F, Dokania N, Dolan S, Doyle TA, Drapier O, Dumarchez J, Dunne P, Eguchi A, Eklund L, Emery-Schrenk S, Ereditato A, Fernandez P, Feusels T, Finch AJ, Fiorentini GA, Fiorillo G, Francois C, Friend M, Fujii Y, Fujita R, Fukuda D, Fukuda R, Fukuda Y, Fusshoeller K, Gameil K, Giganti C, Golan T, Gonin M, Gorin A, Guigue M, Hadley DR, Haigh JT, Hamacher-Baumann P, Harris DA, Hartz M, Hasegawa T, Hassani S, Hastings NC, Hayashino T, Hayato Y, Hiramoto A, Hogan M, Holeczek J, Van NTH, Honjo T, Iacob F, Ichikawa AK, Ikeda M, Ishida T, Ishii T, Ishitsuka M, Iwamoto K, Izmaylov A, Izumi N, Jakkapu M, Jamieson B, Jenkins SJ, Jesus-Valls C, Jiang M, Johnson S, Jonsson P, Jung CK, Jurj PB, Kabirnezhad M, Kaboth AC, Kajita T, Kakuno H, Kameda J, Karlen D, Kasetti SP, Kataoka Y, Katayama Y, Katori T, Kato Y, Kearns E, Khabibullin M, Khotjantsev A, Kikawa T, Kikutani H, Kim H, Kim J, King S, Kisiel J, Knight A, Knox A, Kobata T, Kobayashi T, Koch L, Koga T, Konaka A, Kormos LL, Koshio Y, Kostin A, Kowalik K, Kubo H, Kudenko Y, Kukita N, Kuribayashi S, Kurjata R, Kutter T, Kuze M, Labarga L, Lagoda J, Lamoureux M, Last D, Laveder M, Lawe M, Licciardi M, Lindner T, Litchfield RP, Liu SL, Li X, Longhin A, Ludovici L, Lu X, Lux T, Machado LN, Magaletti L, Maet al., 2021, Measurements of (nu)over-bar(mu) and (nu)over-bar(mu) + nu(mu) charged-current cross-sections without detected pions or protons on water and hydrocarbon at a mean anti-neutrino energy of 0.86 GeV, PROGRESS OF THEORETICAL AND EXPERIMENTAL PHYSICS, Vol: 2021, ISSN: 2050-3911

Journal article

Abe K, Akhlaq N, Akutsu R, Ali A, Alt C, Andreopoulos C, Antonova M, Aoki S, Arihara T, Asada Y, Ashida Y, Atkin ET, Awataguchi Y, Barker GJ, Barr G, Barrow D, Batkiewicz-Kwasniak M, Beloshapkin A, Bench F, Berardi V, Berns L, Bhadra S, Blondel A, Bolognesi S, Bonus T, Bourguille B, Boyd SB, Bravar A, Berguno DB, Bronner C, Bron S, Bubak A, Avanzini MB, Cao S, Cartwright SL, Catanesi MG, Cervera A, Cherdack D, Christodoulou G, Cicerchia M, Coleman J, Collazuol G, Cook L, Coplowe D, Cudd A, De Rosa G, Dealtry T, Delogu CC, Dennis SR, Densham C, Dergacheva A, Di Lodovico F, Dolan S, Doyle TA, Dumarchez J, Dunne P, Eguchi A, Eklund L, Emery-Schrenk S, Ereditato A, Finch AJ, Fiorentini GA, Francois C, Friend M, Fujii Y, Fukuda R, Fukuda Y, Fusshoeller K, Giganti C, Gonin M, Gorin A, Guigue M, Hadley DR, Hamacher-Baumann P, Hartz M, Hasegawa T, Hassani S, Hastings NC, Hayato Y, Hiramoto A, Hogan M, Holeczek J, Van NTH, Honjo T, Iacob F, Ichikawa AK, Ikeda M, Ishida T, Ishitsuka M, Iwamoto K, Izmaylov A, Izumi N, Jakkapu M, Jamieson B, Jenkins SJ, Jesus-Valls C, Jonsson P, Jung CK, Jurj PB, Kabirnezhad M, Kakuno H, Kameda J, Kasetti SP, Kataoka Y, Katayama Y, Katori T, Kearns E, Khabibullin M, Khotjantsev A, Kikawa T, Kikutani H, King S, Kisiel J, Kobata T, Kobayashi T, Koch L, Konaka A, Kormos LL, Koshio Y, Kostin A, Kowalik K, Kudenko Y, Kuribayashi S, Kurjata R, Kutter T, Kuze M, Labarga L, Lagoda J, Lamoureux M, Last D, Laveder M, Lawe M, Litchfield RP, Liu SL, Longhin A, Ludovici L, Lu X, Lux T, Machado LN, Magaletti L, Mahn K, Malek M, Manly S, Maret L, Marino AD, Marti-Magro L, Maruyama T, Matsubara T, Matsushita K, Mauger C, Mavrokoridis K, Mazzucato E, McCauley N, McElwee J, McFarland KS, McGrew C, Mefodiev A, Mezzetto M, Minamino A, Mineev O, Mine S, Miura M, Bueno LM, Moriyama S, Mueller TA, Munteanu L, Nagai Y, Nakadaira T, Nakahata M, Nakajima Y, Nakamura A, Nakamura K, Nakano Y, Nakayama S, Nakaya T, Nakayoshi K, Naseby CER, Ngoc T, Nguyen VQ, Niewczas K, Niet al., 2021, T2K measurements of muon neutrino and antineutrino disappearance using 3.13 x 10(21) protons on target, Physical Review D: Particles, Fields, Gravitation and Cosmology, Vol: 103, Pages: 1-9, ISSN: 1550-2368

We report measurements by the T2K experiment of the parameters θ23 and Δm232, which govern the disappearance of muon neutrinos and antineutrinos in the three-flavor PMNS neutrino oscillation model at T2K’s neutrino energy and propagation distance. Utilizing the ability of the experiment to run with either a mainly neutrino or a mainly antineutrino beam, muon-like events from each beam mode are used to measure these parameters separately for neutrino and antineutrino oscillations. Data taken from 1.49×1021 protons on target (POT) in neutrino mode and 1.64×1021 POT in antineutrino mode are used. The best-fit values obtained by T2K were sin2(θ23)=0.51+0.06−0.07(0.43+0.21−0.05) and Δm232=2.47+0.08−0.09(2.50+0.18−0.13)×10−3  eV2/c4 for neutrinos (antineutrinos). No significant differences between the values of the parameters describing the disappearance of muon neutrinos and antineutrinos were observed. An analysis using an effective two-flavor neutrino oscillation model where the sine of the mixing angle is allowed to take nonphysical values larger than 1 is also performed to check the consistency of our data with the three-flavor model. Our data were found to be consistent with a physical value for the mixing angle.

Journal article

Abe K, Bronner C, Hayato Y, Ikeda M, Imaizumi S, Ito H, Kameda J, Kataoka Y, Miura M, Moriyama S, Nagao Y, Nakahata M, Nakajima Y, Nakayama S, Okada T, Okamoto K, Orii A, Pronost G, Sekiya H, Shiozawa M, Sonoda Y, Suzuki Y, Takeda A, Takemoto Y, Takenaka A, Tanaka H, Yano T, Akutsu R, Han S, Kajita T, Okumura K, Tashiro T, Wang R, Xia J, Bravo-Berguno D, Labarga L, Marti LL, Zaldivar B, Blaszczyk FDM, Kearns E, Gustafson JD, Raaf JL, Stone JL, Wan L, Wester T, Bian J, Griskevich NJ, Kropp WR, Locke S, Mine S, Smy MB, Sobel HW, Takhistov V, Weatherly P, Hill J, Kim JY, Lim IT, Park RG, Bodur B, Scholberg K, Walter CW, Coffani A, Drapier O, El Hedri S, Giampaolo A, Gonin M, Mueller TA, Paganini P, Quilain B, Ishizuka T, Nakamura T, Jang JS, Learned JG, Anthony LH, Sztuc AA, Uchida Y, Berardi V, Catanesi MG, Radicioni E, Calabria NF, Machado LN, De Rosa G, Collazuol G, Iacob F, Lamoureux M, Ospina N, Ludovici L, Nishimura Y, Cao S, Friend M, Hasegawa T, Ishida T, Kobayashi T, Matsubara T, Nakadaira T, Jakkapu M, Nakamura K, Oyama Y, Sakashita K, Sekiguchi T, Tsukamoto T, Nakano Y, Shiozawa T, Suzuki AT, Takeuchi Y, Yamamoto S, Ali A, Ashida Y, Feng J, Hirota S, Ichikawa AK, Kikawa T, Mori M, Nakaya T, Wendell RA, Yasutome K, Fernandez P, McCauley N, Mehta P, Pritchard A, Tsui KM, Fukuda Y, Itow Y, Menjo H, Niwa T, Sato K, Tsukada M, Mijakowski P, Posiadala-Zezula M, Jung CK, Vilela C, Wilking MJ, Yanagisawa C, Harada M, Hagiwara K, Horai T, Ishino H, Ito S, Koshio Y, Ma W, Piplani N, Sakai S, Kuno Y, Barr G, Barrow D, Cook L, Goldsack A, Samani S, Simpson C, Wark D, Nova F, Boschi T, Di Lodovico F, Sedgwick SM, Taani M, Zsoldos S, Yang JY, Jenkins SJ, McElwee JM, Thiesse MD, Thompson LF, Malek M, Stone O, Okazawa H, Kim SB, Yu I, Nishijima K, Koshiba M, Ogawa N, Iwamoto K, Yokoyama M, Martens K, Vagins MR, Kuze M, Izumiyama S, Tanaka M, Yoshida T, Inomoto M, Ishitsuka M, Matsumoto R, Ohta K, Shinoki M, Martin JF, Tanaka HA, Towstego T, Hartz M, Konaka A, de Perio P, Pret al., 2021, Neutron-antineutron oscillation search using a 0.37 megaton-years exposure of Super-Kamiokande, PHYSICAL REVIEW D, Vol: 103, ISSN: 2470-0010

Journal article

Takenaka A, Abe K, Bronner C, Hayato Y, Ikeda M, Imaizumi S, Ito H, Kameda J, Kataoka Y, Kato Y, Kishimoto Y, Marti L, Miura M, Moriyama S, Mochizuki T, Nagao Y, Nakahata M, Nakajima Y, Nakayama S, Okada T, Okamoto K, Orii A, Pronost G, Sekiya H, Shiozawa M, Sonoda Y, Suzuki Y, Takeda A, Takemoto Y, Tanaka H, Yano T, Akutsu R, Han S, Kajita T, Okumura K, Tashiro T, Wang R, Xia J, Bravo-Berguno D, Labarga L, Fernandez P, Zaldivar B, Blaszczyk FDM, Kearns E, Raaf JL, Stone JL, Wan L, Wester T, Pointon BW, Bian J, Griskevich NJ, Kropp WR, Locke S, Mine S, Smy MB, Sobel HW, Takhistov V, Weatherly P, Ganezer KS, Hill J, Kim JY, Lim IT, Park RG, Bodur B, Scholberg K, Walter CW, Coffani A, Drapier O, El Hedri S, Giampaolo A, Gonin M, Mueller TA, Paganini P, Quilain B, Ishizuka T, Nakamura T, Jang JS, Learned JG, Matsuno S, Anthony LH, Litchfield RP, Sztuc AA, Uchida Y, Berardi V, Catanesi MG, Radicioni E, Calabria NF, Machado LN, De Rosa G, Collazuol G, Iacob F, Lamoureux M, Ospina N, Ludovici L, Nishimura Y, Cao S, Friend M, Hasegawa T, Ishida T, Jakkapu M, Kobayashi T, Matsubara T, Nakadaira T, Nakamura K, Oyama Y, Sakashita K, Sekiguchi T, Tsukamoto T, Hasegawa M, Isobe Y, Miyabe H, Nakano Y, Shiozawa T, Sugimoto T, Suzuki AT, Takeuchi Y, Yamamoto S, Ali A, Ashida Y, Feng J, Hirota S, Ichikawa AK, Jiang M, Kikawa T, Mori M, Nakamura KE, Nakaya T, Wendell RA, Yasutome K, McCauley N, Mehta P, Pritchard A, Tsui KM, Fukuda Y, Itow Y, Menjo H, Niwa T, Sato K, Taani M, Tsukada M, Mijakowski P, Frankiewicz K, Jung CK, Santucci G, Vilela C, Wilking MJ, Yanagisawa C, Fukuda D, Harada M, Hagiwara K, Horai T, Ishino H, Ito S, Koshio Y, Ma K, Piplani N, Sakai S, Sakuda M, Takahira Y, Xu C, Kuno Y, Barr G, Barrow D, Cook L, Simpson C, Wark D, Nova F, Boschi T, Di Lodovico F, Segwick SM, Zsoldos S, Yang JY, Jenkins SJ, McElwee JM, Thiesse MD, Thompson LF, Okazawa H, Choi Y, Kim SB, Yu I, Nishijima K, Koshiba M, Iwamoto K, Ogawa N, Yokoyama M, Goldsack A, Martens K, Vagins MR, Kuze Met al., 2020, Search for proton decay via p -> e(+)pi(0) and p -> mu(+)pi(0) with an enlarged fiducial volume in Super-Kamiokande I-IV, PHYSICAL REVIEW D, Vol: 102, ISSN: 2470-0010

Journal article

Blondel A, Bogomilov M, Bordoni S, Cadoux F, Douqa D, Dugas K, Ekelof T, Favre Y, Fedotov S, Fransson K, Fujita R, Gramstad E, Ichikawa AK, Ilieva S, Iwamoto K, Jesus-Valls C, Jung CK, Kasetti SP, Khabibullin M, Khotjantsev A, Korzenev A, Kostin A, Kudenko Y, Kutter T, Lux T, Maret L, Matsubara T, Mefodiev A, Minamino A, Mineev O, Mitev G, Nessi M, Nicola L, Noah E, Parsa S, Petkov G, Sanchez F, Sgalaberna D, Shorrock W, Skwarczynski K, Suvorov S, Teklu A, Tsenov R, Uchida Y, Vankova-Kirilova G, Yershov N, Yokoyama M, Zalipska J, Zou Y, Zurek Wet al., 2020, The SuperFGD Prototype charged particle beam tests, JOURNAL OF INSTRUMENTATION, Vol: 15, ISSN: 1748-0221

Journal article

Abe K, Bronner C, Haga Y, Hayato Y, Ikeda M, Imaizumi S, Ito H, Iyogi K, Kameda J, Kataoka Y, Kato Y, Kishimoto Y, Marti L, Miura M, Moriyama S, Mochizuki T, Nagao Y, Nakahata M, Nakajima Y, Nakajima T, Nakayama S, Okada T, Okamoto K, Orii A, Pronost G, Sekiya H, Shiozawa M, Sonoda Y, Takeda A, Takenaka A, Tanaka H, Tasaka S, Tomura T, Ueno K, Yano T, Yokozawa T, Akutsu R, Han S, Irvine T, Kajita T, Kametani I, Lee KP, McLachlan T, Okumura K, Richard E, Tashiro T, Wang R, Xia J, Bravo-Berguno D, Labarga L, Fernandez P, Blaszczyk FDM, Gustafson J, Kachulis C, Kearns E, Raaf JL, Stone JL, Sulak LR, Sussman S, Wan L, Wester T, Berkman S, Tobayama S, Bian J, Carminati G, Elnimr M, Griskevich NJ, Kropp WR, Locke S, Mine S, Renshaw A, Smy MB, Sobel HW, Takhistov V, Weatherly P, Hartfiel BL, Hill J, Keig WE, Hong N, Kim JY, Lim IT, Park RG, Akiri T, Bodur B, Himmel A, Li Z, O'Sullivan E, Scholberg K, Walter CW, Wongjirad T, Coffani A, Drapier O, El Hedri S, Giampaolo A, Gonin M, Imber J, Mueller TA, Paganini P, Quilain B, Ishizuka T, Nakamura T, Jang JS, Choi K, Learned JG, Matsuno S, Smith SN, Amey J, Anthony LH, Litchfield RP, Sztuc AA, Uchida Y, Wascko MO, Berardi V, Catanesi MG, Intonti RA, Radicioni E, Calabria NF, Machado LN, De Rosa G, Collazuol G, Iacob F, Lamoureux M, Ospina N, Ludovici L, Boschi T, Di Lodovico F, Sedgwick SM, Zsoldos S, Nishimura Y, Cao S, Friend M, Hasegawa T, Ishida T, Ishii T, Kobayashi T, Nakadaira T, Nakamura K, Oyama Y, Sakashita K, Sekiguchi T, Tsukamoto T, Abe K, Hasegawa M, Isobe Y, Miyabe H, Nakano Y, Shiozawa T, Sugimoto T, Suzuki AT, Takeuchi Y, Yamamoto S, Ali A, Ashida Y, Hayashino T, Hiraki T, Hirota S, Huang K, Ieki K, Jiang M, Kikawa T, Mori M, Murakami A, Nakamura KE, Nakaya T, Patel ND, Suzuki K, Takahashi S, Tateishi K, Wendell RA, McCauley N, Mehta P, Pritchard A, Tsui KM, Fukuda Y, Itow Y, Menjo H, Mitsuka G, Murase M, Muto F, Niwa T, Sato K, Suzuki T, Taani M, Tsukada M, Mijakowski P, Frankiewicz K, Hignight J, Jung CK, Liet al., 2020, Indirect search for dark matter from the Galactic Center and halo with the Super-Kamiokande detector, Physical Review D: Particles, Fields, Gravitation and Cosmology, Vol: 102, Pages: 072002 – 1-072002 – 14, ISSN: 1550-2368

We present a search for an excess of neutrino interactions due to dark matter in the form of weakly interacting massive particles (WIMPs) annihilating in the Galactic center or halo based on the data set of Super-Kamiokande-I, -II, -III and -IV taken from 1996 to 2016. We model the neutrino flux, energy, and flavor distributions assuming WIMP self-annihilation is dominant to ν¯ν, μ+μ−, b¯b, or W+W−. The excess is in comparison to atmospheric neutrino interactions which are modeled in detail and fit to data. Limits on the self-annihilation cross section ⟨σAV⟩ are derived for WIMP masses in the range 1 GeV to 10 TeV, reaching as low as 9.6×10−23  cm3 s−1 for 5 GeV WIMPs in b¯b mode and 1.2×10−24  cm3 s−1 for 1 GeV WIMPs in ν¯ν mode. The obtained sensitivity of the Super-Kamiokande detector to WIMP masses below several tens of GeV is the best among similar indirect searches to date.

Journal article

Abe K, Akhlaq N, Akutsu R, Ali A, Alt C, Andreopoulos C, Anthony L, Antonova M, Aoki S, Ariga A, Arihara T, Asada Y, Ashida Y, Atkin ET, Awataguchi Y, Ban S, Barbi M, Barker GJ, Barr G, Barrow D, Barry C, Batkiewicz-Kwasniak M, Beloshapkin A, Bench F, Berardi V, Berns L, Bhadra S, Bienstock S, Blondel A, Bolognesi S, Bonus T, Bourguille B, Boyd SB, Brailsford D, Bravar A, Bravo Berguño D, Bronner C, Bron S, Bubak A, Buizza Avanzini M, Calcutt J, Campbell T, Cao S, Cartwright SL, Catanesi MG, Cervera A, Chappell A, Checchia C, Cherdack D, Chikuma N, Christodoulou G, Cicerchia M, Coleman J, Collazuol G, Cook L, Coplowe D, Cudd A, Dabrowska A, De Rosa G, Dealtry T, Denner PF, Dennis SR, Densham C, Di Lodovico F, Dokania N, Dolan S, Doyle TA, Drapier O, Dumarchez J, Dunne P, Eguchi A, Eklund L, Emery-Schrenk S, Ereditato A, Fernandez P, Feusels T, Finch AJ, Fiorentini GA, Fiorillo G, Francois C, Friend M, Fujii Y, Fujita R, Fukuda D, Fukuda R, Fukuda Y, Fusshoeller K, Giganti C, Golan T, Gonin M, Gorin A, Guigue M, Hadley DR, Haigh JT, Hamacher-Baumann P, Hartz M, Hasegawa T, Hassani S, Hastings NC, Hayashino T, Hayato Y, Hiramoto A, Hogan M, Holeczek J, Hong Van NT, Honjo T, Iacob F, Ichikawa AK, Ikeda M, Ishida T, Ishii T, Ishitsuka M, Iwamoto K, Izmaylov A, Izumi N, Jakkapu M, Jamieson B, Jenkins SJ, Jesús-Valls C, Jiang M, Johnson S, Jonsson P, Jung CK, Junjie X, Jurj PB, Kabirnezhad M, Kaboth AC, Kajita T, Kakuno H, Kameda J, Karlen D, Kasetti SP, Kataoka Y, Katayama Y, Katori T, Kato Y, Kearns E, Khabibullin M, Khotjantsev A, Kikawa T, Kikutani H, Kim H, King S, Kisiel J, Knight A, Knox A, Kobata T, Kobayashi T, Koch L, Koga T, Konaka A, Kormos LL, Koshio Y, Kostin A, Kowalik K, Kubo H, Kudenko Y, Kukita N, Kuribayashi S, Kurjata R, Kutter T, Kuze M, Labarga L, Lagoda J, Lamoureux M, Last D, Laveder M, Lawe M, Licciardi M, Lindner T, Litchfield RP, Liu SL, Li X, Longhin A, Ludovici L, Lu X, Lux T, Machado LN, Magaletti L, Mahn K, Malek M, Manly S, Maret L, Marinoet al., 2020, Measurement of the charged-current electron (anti-)neutrino inclusive cross-sections at the T2K off-axis near detector ND280, The Journal of High Energy Physics, Vol: 2020, Pages: 1-43, ISSN: 1029-8479

The electron (anti-)neutrino component of the T2K neutrino beam constitutes the largest background in the measurement of electron (anti-)neutrino appearance at the far detector. The electron neutrino scattering is measured directly with the T2K off-axis near detector, ND280. The selection of the electron (anti-)neutrino events in the plastic scintillator target from both neutrino and anti-neutrino mode beams is discussed in this paper. The flux integrated single differential charged-current inclusive electron (anti-)neutrino cross-sections, dσ/dp and dσ/d cos(θ), and the total cross-sections in a limited phase-space in momentum and scattering angle (p > 300 MeV/c and θ ≤ 45°) are measured using a binned maximum likelihood fit and compared to the neutrino Monte Carlo generator predictions, resulting in good agreement.

Journal article

Abe K, Akutsu R, Ali A, Alt C, Andreopoulos C, Anthony L, Antonova M, Aoki S, Ariga A, Ashida Y, Atkin ET, Awataguchi Y, Ban S, Barbi M, Barker GJ, Barr G, Barry C, Batkiewicz-Kwasniak M, Beloshapkin A, Bench F, Berardi V, Berkman S, Berns L, Bhadra S, Bienstock S, Blondel A, Bolognesi S, Bourguille B, Boyd SB, Brailsford D, Bravar A, Bronner C, Avanzini MB, Calcutt J, Campbell T, Cao S, Cartwright SL, Catanesi MG, Cervera A, Chappell A, Checchia C, Cherdack D, Chikuma N, Christodoulou G, Coleman J, Collazuol G, Cook L, Coplowe D, Cudd A, Dabrowska A, De Rosa G, Dealtry T, Denner PF, Dennis SR, Densham C, Di Lodovico F, Dokania N, Dolan S, Drapier O, Dumarchez J, Dunne P, Eklund L, Emery-Schrenk S, Ereditato A, Fernandez P, Feusels T, Finch AJ, Fiorentini GA, Fiorillo G, Francois C, Friend M, Fujii Y, Fujita R, Fukuda D, Fukuda R, Fukuda Y, Gameil K, Giganti C, Golan T, Gonin M, Gorin A, Guigue M, Hadley DR, Haigh JT, Hamacher-Baumann P, Hartz M, Hasegawa T, Hastings NC, Hayashino T, Hayato Y, Hiramoto A, Hogan M, Holeczek J, Hong Van NT, Iacob F, Ichikawa AK, Ikeda M, Ishida T, Ishii T, Ishitsuka M, Iwamoto K, Izmaylov A, Jamieson B, Jenkins SJ, Jesus-Valls C, Jiang M, Johnson S, Jonsson P, Jung CK, Kabirnezhad M, Kaboth AC, Kajita T, Kakuno H, Kameda J, Karlen D, Kataoka Y, Katori T, Kato Y, Kearns E, Khabibullin M, Khotjantsev A, Kim H, Kim J, King S, Kisiel J, Knight A, Knox A, Kobayashi T, Koch L, Koga T, Konaka A, Kormos LL, Koshio Y, Kowalik K, Kubo H, Kudenko Y, Kukita N, Kurjata R, Kutter T, Kuze M, Labarga L, Lagoda J, Lamoureux M, Laveder M, Lawe M, Licciardi M, Lindner T, Litchfield RP, Liu SL, Li X, Longhin A, Ludovici L, Lu X, Lux T, Magaletti L, Mahn K, Malek M, Manly S, Maret L, Marino AD, Martin JF, Maruyama T, Matsubara T, Matsushita K, Matveev V, Mavrokoridis K, Mazzucato E, McCarthy M, McCauley N, McFarland KS, McGrew C, Mefodiev A, Metelko C, Mezzetto M, Minamino A, Mineev O, Mine S, Miura M, Bueno LM, Moriyama S, Morrison J, Mueller TA, Munteanet al., 2020, First measurement of the charged current (nu)over-bar(mu) double differential cross section on a water target without( )pions in the final state, Physical Review D: Particles, Fields, Gravitation and Cosmology, Vol: 102, Pages: 1-16, ISSN: 1550-2368

This paper reports the first differential measurement of the charged-current ¯νμ interaction cross section on water with no pions in the final state. The unfolded flux-averaged measurement using the T2K off-axis near detector is given in double-differential bins of μ+ momentum and angle. The integrated cross section in a restricted phase space is σ=(1.11±0.18)×10−38  cm2 per water molecule. Comparisons with several nuclear models are also presented.

Journal article

Abe K, Akhlaq N, Akutsu R, Ali A, Alt C, Andreopoulos C, Anthony L, Antonova M, Aoki S, Ariga A, Arihara T, Asada Y, Ashida Y, Atkin ET, Awataguchi Y, Ban S, Barbi M, Barker GJ, Barr G, Barrow D, Batkiewicz-Kwasniak M, Beloshapkin A, Bench F, Berardi V, Berns L, Bhadra S, Bienstock S, Bolognesi S, Bonus T, Bourguille B, Boyd SB, Bravar A, Bravo Berguno D, Bronner C, Bron S, Bubak A, Avanzini MB, Campbell T, Cao S, Cartwright SL, Catanesi MG, Cervera A, Cherdack D, Chikuma N, Christodoulou G, Cicerchia M, Coleman J, Collazuol G, Cook L, Coplowe D, Cudd A, Dabrowska A, De Rosa G, Dealtry T, Dennis SR, Densham C, Di Lodovico F, Dokania N, Dolan S, Doyle TA, Drapier O, Dumarchez J, Dunne P, Eguchi A, Eklund L, Emery-Schrenk S, Ereditato A, Finch AJ, Fiorillo G, Francois C, Friend M, Fujii Y, Fujita R, Fukuda D, Fukuda R, Fukuda Y, Fusshoeller K, Giganti C, Gonin M, Gorin A, Guigue M, Hadley DR, Haigh JT, Hamacher-Baumann P, Hartz M, Hasegawa T, Hassani S, Hastings NC, Hayato Y, Hiramoto A, Hogan M, Holeczek J, Van NTH, Honjo T, Iacob F, Ichikawa AK, Ikeda M, Ishida T, Ishitsuka M, Iwamoto K, Izmaylov A, Izumi N, Jakkapu M, Jamieson B, Jenkins SJ, Jesus-Valls C, Jiang M, Jonsson P, Jung CK, Junjie X, Jurj PB, Kabirnezhad M, Kaboth AC, Kajita T, Kakuno H, Kameda J, Karlen D, Kasetti SP, Kataoka Y, Katayama Y, Katori T, Kato Y, Kearns E, Khabibullin M, Khotjantsev A, Kikawa T, Kikutani H, Kim H, King S, Kisiel J, Knight A, Kobata T, Kobayashi T, Koch L, Koga T, Konaka A, Kormos LL, Koshio Y, Kostin A, Kowalik K, Kubo H, Kudenko Y, Kukita N, Kuribayashi S, Kurjata R, Kutter T, Kuze M, Labarga L, Lagoda J, Lamoureux M, Last D, Lawe M, Licciardi M, Litchfield RP, Liu SL, Li X, Longhin A, Ludovici L, Lu X, Lux T, Machado LN, Magaletti L, Mahn K, Malek M, Manly S, Maret L, Marino AD, Marti-Magro L, Maruyama T, Matsubara T, Matsushita K, Matveev V, Mauger C, Mavrokoridis K, Mazzucato E, McCauley N, McElwee J, McFarland KS, McGrew C, Mefodiev A, Metelko C, Mezzetto M, Minamino Aet al., 2020, Simultaneous measurement of the muon neutrino charged-current cross section on oxygen and carbon without pions in the final state at T2K, Physical Review D: Particles, Fields, Gravitation and Cosmology, Vol: 101, Pages: 112004 – 1-112004 – 32, ISSN: 1550-2368

This paper reports the first simultaneous measurement of the double differential muon neutrino charged-current cross section on oxygen and carbon without pions in the final state as a function of the outgoing muon kinematics, made at the ND280 off-axis near detector of the T2K experiment. The ratio of the oxygen and carbon cross sections is also provided to help validate various models’ ability to extrapolate between carbon and oxygen nuclear targets, as is required in T2K oscillation analyses. The data are taken using a neutrino beam with an energy spectrum peaked at 0.6 GeV. The extracted measurement is compared with the prediction from different Monte Carlo neutrino-nucleus interaction event generators, showing particular model separation for very forward-going muons. Overall, of the models tested, the result is best described using local Fermi gas descriptions of the nuclear ground state with RPA suppression.

Journal article

Abe K, Akhlaq N, Akutsu R, Ali A, Alt C, Andreopoulos C, Anthony L, Antonova M, Aoki S, Ariga A, Arihara T, Asada Y, Ashida Y, Atkin ET, Awataguchi Y, Ban S, Barbi M, Barker GJ, Barr G, Barrow D, Barry C, Batkiewicz-Kwasniak M, Beloshapkin A, Bench F, Berardi V, Berns L, Bhadra S, Bienstock S, Blondel A, Bolognesi S, Bonus T, Bourguille B, Boyd SB, Brailsford D, Bravar A, Bravo Berguno D, Bronner C, Bron S, Bubak A, Avanzini MB, Calcutt J, Campbell T, Cao S, Cartwright SL, Catanesi MG, Cervera A, Chappell A, Checchia C, Cherdack D, Chikuma N, Christodoulou G, Cicerchia M, Coleman J, Collazuol G, Cook L, Coplowe D, Cudd A, Dabrowska A, De Rosa G, Dealtry T, Denner PF, Dennis SR, Densham C, Di Lodovico F, Dokania N, Dolan S, Doyle TA, Drapier O, Dumarchez J, Dunne P, Eguchi A, Eklund L, Emery-Schrenk S, Ereditato A, Fernandez P, Feusels T, Finch AJ, Fiorentini GA, Fiorillo G, Francois C, Friend M, Fujii Y, Fujita R, Fukuda D, Fukuda R, Fukuda Y, Fusshoeller K, Giganti C, Golan T, Gonin M, Gorin A, Guigue M, Hadley DR, Haigh JT, Hamacher-Baumann P, Hartz M, Hasegawa T, Hassani S, Hastings NC, Hayashino T, Hayato Y, Hiramoto A, Hogan M, Holeczek J, Van NTH, Honjo T, Iacob F, Ichikawa AK, Ikeda M, Ishida T, Ishii T, Ishitsuka M, Iwamoto K, Izmaylov A, Izumi N, Jakkapu M, Jamieson B, Jenkins SJ, Jesus-Valls C, Jiang M, Johnson S, Jonsson P, Jung CK, Junjie X, Jurj PB, Kabirnezhad M, Kaboth AC, Kajita T, Kakuno H, Kameda J, Karlen D, Kasetti SP, Kataoka Y, Katayama Y, Katori T, Kato Y, Kearns E, Khabibullin M, Khotjantsev A, Kikawa T, Kikutani H, Kim H, King S, Kisiel J, Knight A, Knox A, Kobata T, Kobayashi T, Koch L, Koga T, Konaka A, Kormos LL, Koshio Y, Kostin A, Kowalik K, Kubo H, Kudenko Y, Kukita N, Kuribayashi S, Kurjata R, Kutter T, Kuze M, Labarga L, Lagoda J, Lamoureux M, Last D, Laveder M, Lawe M, Licciardi M, Lindner T, Litchfield RP, Liu SL, Li X, Longhin A, Ludovici L, Lu X, Lux T, Machado LN, Magaletti L, Mahn K, Malek M, Manly S, Maret L, Marino AD, Marti-et al., 2020, First combined measurement of the muon neutrino and antineutrino charged-current cross section without pions in the final state at T2K, Physical Review D: Particles, Fields, Gravitation and Cosmology, Vol: 101, Pages: 112001 – 1-112001 – 44, ISSN: 1550-2368

This paper presents the first combined measurement of the double-differential muon neutrino and antineutrino charged-current cross sections with no pions in the final state on hydrocarbon at the off-axis near detector of the T2K experiment. The data analyzed in this work comprise 5.8×1020 and 6.3×1020 protons on target in neutrino and antineutrino mode respectively, at a beam energy peak of 0.6 GeV. Using the two measured cross sections, the sum, difference, and asymmetry were calculated with the aim of better understanding the nuclear effects involved in such interactions. The extracted measurements have been compared with the prediction from different Monte Carlo generators and theoretical models showing that the difference between the two cross sections have interesting sensitivity to nuclear effects.

Journal article

Abe K, Akutsu R, Ali A, Alt C, Andreopoulos C, Anthony L, Antonova M, Aoki S, Ariga A, Asada Y, Ashida Y, Atkin ET, Awataguchi Y, Ban S, Barbi M, Barker GJ, Barr G, Barrow D, Barry C, Batkiewicz-Kwasniak M, Beloshapkin A, Bench F, Berardi V, Berkman S, Berns L, Bhadra S, Bienstock S, Blondel A, Bolognesi S, Bourguille B, Boyd SB, Brailsford D, Bravar A, Bravo Berguno D, Bronner C, Bubak A, Avanzini MB, Calcutt J, Campbell T, Cao S, Cartwright SL, Catanesi MG, Cervera A, Chappell A, Checchia C, Cherdack D, Chikuma N, Christodoulou G, Coleman J, Collazuol G, Cook L, Coplowe D, Cudd A, Dabrowska A, De Rosa G, Dealtry T, Denner PF, Dennis SR, Densham C, Di Lodovico F, Dokania N, Dolan S, Doyle TA, Drapier O, Dumarchez J, Dunne P, Eklund L, Emery-Schrenk S, Ereditato A, Fernandez P, Feusels T, Finch AJ, Fiorentini GA, Fiorillo G, Francois C, Friend M, Fujii Y, Fujita R, Fukuda D, Fukuda R, Fukuda Y, Fusshoeller K, Gameil K, Giganti C, Golan T, Gonin M, Gorin A, Guigue M, Hadley DR, Haigh JT, Hamacher-Baumann P, Hartz M, Hasegawa T, Hastings NC, Hayashino T, Hayato Y, Hiramoto A, Hogan M, Holeczek J, Van NTH, Iacob F, Ichikawa AK, Ikeda M, Ishida T, Ishii T, Ishitsuka M, Iwamoto K, Izmaylov A, Jakkapu M, Jamieson B, Jenkins SJ, Jesus-Valls C, Jiang M, Johnson S, Jonsson P, Jung CK, Kabirnezhad M, Kaboth AC, Kajita T, Kakuno H, Kameda J, Karlen D, Kasetti SP, Kataoka Y, Katori T, Kato Y, Kearns E, Khabibullin M, Khotjantsev A, Kikawa T, Kim H, Kim J, King S, Kisiel J, Knight A, Knox A, Kobayashi T, Koch L, Koga T, Konaka A, Kormos LL, Koshio Y, Kostin A, Kowalik K, Kubo H, Kudenko Y, Kukita N, Kuribayashi S, Kurjata R, Kutter T, Kuze M, Labarga L, Lagoda J, Lamoureux M, Laveder M, Lawe M, Licciardi M, Lindner T, Litcheld RP, Liu SL, Li X, Longhin A, Ludovici L, Lu X, Lux T, Machado LN, Magaletti L, Mahn K, Malek M, Manly S, Maret L, Marino AD, Marti-Magro L, Martin JF, Maruyama T, Matsubara T, Matsushita K, Matveev V, Mavrokoridis K, Mazzucato E, McCarthy M, McCauley N, Mcet al., 2020, Search for electron antineutrino appearance in a long-baseline muon antineutrino beam, Physical Review Letters, Vol: 124, Pages: 161802-1-161802-8, ISSN: 0031-9007

Electron antineutrino appearance is measured by the T2K experiment in an accelerator-produced antineutrino beam, using additional neutrino beam operation to constrain parameters of the Pontecorvo-Maki-Nakagawa-Sakata (PMNS) mixing matrix. T2K observes 15 candidate electron antineutrino events with a background expectation of 9.3 events. Including information from the kinematic distribution of observed events, the hypothesis of no electron antineutrino appearance is disfavored with a significance of 2.40σ and no discrepancy between data and PMNS predictions is found. A complementary analysis that introduces an additional free parameter which allows non-PMNS values of electron neutrino and antineutrino appearance also finds no discrepancy between data and PMNS predictions.

Journal article

Abe K, Akutsu R, Ali A, Alt C, Andreopoulos C, Anthony L, Antonova M, Aoki S, Ariga A, Ashida Y, Atkin ET, Awataguchi Y, Ban S, Barbi M, Barker GJ, Barr G, Barry C, Batkiewicz-Kwasniak M, Beloshapkin A, Bench F, Berardi V, Berkman S, Berns L, Bhadra S, Bienstock S, Blondel A, Bolognesi S, Bourguille B, Boyd SB, Brailsford D, Bravar A, Berguno DB, Bronner C, Bubak A, Avanzini MB, Calcutt J, Campbell T, Cao S, Cartwright SL, Catanesi MG, Cervera A, Chappell A, Checchia C, Cherdack D, Chikuma N, Christodoulou G, Coleman J, Collazuol G, Cook L, Coplowe D, Cudd A, Dabrowska A, De Rosa G, Dealtry T, Denner PF, Dennis SR, Densham C, Di Lodovico F, Dokania N, Dolan S, Drapier O, Dumarchez J, Dunne P, Eklund L, Emery-Schrenk S, Ereditato A, Fernandez P, Feusels T, Finch AJ, Fiorentini GA, Fiorillo G, Francois C, Friend M, Fujii Y, Fujita R, Fukuda D, Fukuda R, Fukuda Y, Gameil K, Giganti C, Golan T, Gonin M, Gorin A, Guigue M, Hadley DR, Haigh JT, Hamacher-Baumann P, Hartz M, Hasegawa T, Hastings NC, Hayashino T, Hayato Y, Hiramoto A, Hogan M, Holeczek J, Hong Van NT, Iacob F, Ichikawa AK, Ikeda M, Ishida T, Ishii T, Ishitsuka M, Iwamoto K, Izmaylov A, Jamieson B, Jenkins SJ, Jesus-Valls C, Jiang M, Johnson S, Jonsson P, Jung CK, Kabirnezhad M, Kaboth AC, Kajita T, Kakuno H, Kameda J, Karlen D, Kasetti SP, Kataoka Y, Katori T, Kato Y, Kearns E, Khabibullin M, Khotjantsev A, Kikawa T, Kim H, Kim J, King S, Kisiel J, Knight A, Knox A, Kobayashi T, Koch L, Koga T, Konaka A, Kormos LL, Koshio Y, Kowalik K, Kubo H, Kudenko Y, Kukita N, Kuribayashi S, Kurjata R, Kutter T, Kuze M, Labarga L, Lagoda J, Lamoureux M, Laveder M, Lawe M, Licciardi M, Lindner T, Litchfield RP, Liu SL, Li X, Longhin A, Ludovici L, Lu X, Lux T, Machado LN, Magaletti L, Mahn K, Malek M, Manly S, Maret L, Marino AD, Martin JF, Maruyama T, Matsubara T, Matsushita K, Matveev V, Mavrokoridis K, Mazzucato E, McCarthy M, McCauley N, McFarland KS, McGrew C, Mefodiev A, Metelko C, Mezzetto M, Minamino A, Mineev Oet al., 2020, Constraint on the matter-antimatter symmetry-violating phase in neutrino oscillations, Nature, Vol: 580, Pages: 339-344, ISSN: 0028-0836

The charge-conjugation and parity-reversal (CP) symmetry of fundamental particles is a symmetry between matter and antimatter. Violation of this CP symmetry was first observed in 19641, and CP violation in the weak interactions of quarks was soon established2. Sakharov proposed3 that CP violation is necessary to explain the observed imbalance of matter and antimatter abundance in the Universe. However, CP violation in quarks is too small to support this explanation. So far, CP violation has not been observed in non-quark elementary particle systems. It has been shown that CP violation in leptons could generate the matter–antimatter disparity through a process called leptogenesis4. Leptonic mixing, which appears in the standard model’s charged current interactions5,6, provides a potential source of CP violation through a complex phase δCP, which is required by some theoretical models of leptogenesis7,8,9. This CP violation can be measured in muon neutrino to electron neutrino oscillations and the corresponding antineutrino oscillations, which are experimentally accessible using accelerator-produced beams as established by the Tokai-to-Kamioka (T2K) and NOvA experiments10,11. Until now, the value of δCP has not been substantially constrained by neutrino oscillation experiments. Here we report a measurement using long-baseline neutrino and antineutrino oscillations observed by the T2K experiment that shows a large increase in the neutrino oscillation probability, excluding values of δCP that result in a large increase in the observed antineutrino oscillation probability at three standard deviations (3σ). The 3σ confidence interval for δCP, which is cyclic and repeats every 2π, is [−3.41, −0.03] for the so-called normal mass ordering and [−2.54, −0.32] for the inverted mass ordering. Our results indicate CP violation in leptons and our method enables sensitive searches for matter–antimatter

Journal article

Tanaka M, Abe K, Bronner C, Hayato Y, Ikeda M, Imaizumi S, Ito H, Kameda J, Kataoka Y, Kato Y, Kishimoto Y, Marti L, Miura M, Moriyama S, Mochizuki T, Nakahata M, Nakajima Y, Nakayama S, Okada T, Okamoto K, Orii A, Pronost G, Sekiya H, Shiozawa M, Sonoda Y, Takeda A, Takenaka A, Tanaka H, Yano T, Akutsu R, Kajita T, Okumura K, Wang R, Xia J, Bravo-Berguno D, Labarga L, Fernandez P, Blaszczyk FDM, Kearns E, Raaf JL, Stone JL, Wan L, Wester T, Bian J, Griskevich NJ, Kropp WR, Locke S, Mine S, Smy MB, Sobel HW, Takhistov V, Weatherly P, Hill J, Kim JY, Lim IT, Park RG, Bodur B, Scholberg K, Walter CW, Coffani A, Drapier O, El Hedri S, Gonin M, Mueller TA, Paganini P, Ishizuka T, Nakamura T, Jang JS, Learned JG, Matsuno S, Litchfield RP, Sztuc AA, Uchida Y, Berardi V, Catanesi MG, Radicioni E, Calabria NF, De Rosa G, Collazuol G, Iacob F, Ludovici L, Nishimura Y, Cao S, Friend M, Hasegawa T, Ishida T, Kobayashi T, Nakadaira T, Nakamura K, Oyama Y, Sakashita K, Sekiguchi T, Tsukamoto T, Hasegawa M, Isobe Y, Miyabe H, Nakano Y, Shiozawa T, Sugimoto T, Suzuki AT, Takeuchi Y, Ali A, Ashida Y, Hirota S, Jiang M, Kikawa T, Mori M, Nakamura K, Nakaya T, Wendell RA, Anthony LH, McCauley N, Mehta P, Pritchard A, Tsui KM, Fukuda Y, Itow Y, Niwa T, Taani M, Tsukada M, Mijakowski P, Frankiewicz K, Jung CK, Vilela C, Wilking MJ, Yanagisawa C, Fukuda D, Harada M, Hagiwara K, Horai T, Ishino H, Ito S, Koshio Y, Sakuda M, Takahira Y, Xu C, Kuno Y, Barrow D, Cook L, Simpson C, Wark D, Nova F, Boschi T, Di Lodovico F, Sedgwick SM, Zsoldos S, Kim SB, Yang JY, Thiesse M, Thompson L, Okazawa H, Choi Y, Nishijima K, Koshiba M, Yokoyama M, Goldsack A, Martens K, Quilain B, Suzuki Y, Vagins MR, Kuze M, Yoshida T, Ishitsuka M, Matsumoto R, Ohta K, Martin JF, Nantais CM, Tanaka HA, Towstego T, Hartz M, Konaka A, de Perio P, Prouse NW, Chen S, Xu BD, Richards B, Jamieson B, Walker J, Minamino A, Pintaudi Get al., 2020, Search for proton decay into three charged leptons in 0.37 megaton-years exposure of the Super-Kamiokande, Physical Review D: Particles, Fields, Gravitation and Cosmology, Vol: 101, Pages: 052011 – 1-052011 – 12, ISSN: 1550-2368

A search for proton decay into three charged leptons has been performed by using 0.37  Mton⋅years of data collected in Super-Kamiokande. All possible combinations of electrons, muons, and their antiparticles consistent with charge conservation were considered as decay modes. No significant excess of events has been found over the background, and lower limits on the proton lifetime divided by the branching ratio have been obtained. The limits range between 9.2×1033 and 3.4×1034  years at 90% confidence level, improving by more than an order of magnitude upon limits from previous experiments. A first limit has been set for the p→μ−e+e+ mode.

Journal article

Abramishvili R, Adamov G, Akhmetshin RR, Allin A, Angelique JC, Anishchik V, Aoki M, Aznabayev D, Bagaturia I, Ban G, Ban Y, Bauer D, Baygarashev D, Bondar AE, Carloganu C, Carniol B, Chau TT, Chen JK, Chen SJ, Cheung YE, da Silva W, Dauncey PD, Densham C, Devidze G, Dornan P, Drutskoy A, Duginov V, Eguchi Y, Epshteyn LB, Evtoukhovitch P, Fayer S, Fedotovich GV, Finger M, Finger M, Fujii Y, Fukao Y, Gabriel JL, Gay P, Gillies E, Grigoriev DN, Gritsay K, Hai VH, Hamada E, Hashim IH, Hashimoto S, Hayashi O, Hayashi T, Hiasa T, Ibrahim ZA, Igarashi Y, Ignatov FV, Iio M, Ishibashi K, Issadykov A, Itahashi T, Jansen A, Jiang XS, Jonsson P, Kachelhoffer T, Kalinnikov V, Kaneva E, Kapusta F, Katayama H, Kawagoe K, Kawashima R, Kazak N, Kazanin VF, Kemularia O, Khvedelidze A, Koike M, Kormoll T, Kozlov GA, Kozyrev AN, Kravchenko M, Krikler B, Kumsiashvili G, Kuno Y, Kuriyama Y, Kurochkin Y, Kurup A, Lagrange B, Lai J, Lee MJ, Li HB, Litchfield RP, Li WG, Loan T, Lomidze D, Lomidze I, Loveridge P, Macharashvili G, Makida Y, Mao YJ, Markin O, Matsuda Y, Melkadze A, Melnik A, Mibe T, Mihara S, Miyamoto N, Miyazaki Y, Idris FM, Azmi KAMK, Moiseenko A, Moritsu M, Mori Y, Motoishi T, Nakai H, Nakai Y, Nakamoto T, Nakamura Y, Nakatsugawa Y, Nakazawa Y, Nash J, Natori H, Niess V, Nioradze M, Nishiguchi H, Noguchi K, Numao T, O'Dell J, Ogitsu T, Ohta S, Oishi K, Okamoto K, Okamura T, Okinaka K, Omori C, Ota T, Pasternak J, Paulau A, Picters D, Ponariadov V, Quemener G, Ruban AA, Rusinov V, Sabirov B, Sakamoto H, Sarin P, Sasaki K, Sato A, Sato J, Semertzidis YK, Shigyo N, Shoukavy D, Slunecka M, Stoeckinger D, Sugano M, Tachimoto T, Takayanagi T, Tanaka M, Tang J, Tao CV, Teixeira AM, Tevzadze Y, Thanh T, Tojo J, Tolmachev SS, Tomasek M, Tomizawa M, Toriashvili T, Trang H, Trekov I, Tsamalaidze Z, Tsverava N, Uchida T, Uchida Y, Ueno K, Velicheva E, Volkov A, Vrba V, Abdullah WATW, Warin-Charpentier P, Wong ML, Wong TS, Wu C, Xing TY, Yamaguchi H, Yamamoto A, Yamanaka M, Yamane T Yet al., 2020, COMET phase-I technical design report, Progress of Theoretical and Experimental Physics, Vol: 2020, ISSN: 2050-3911

The Technical Design for the COMET Phase-I experiment is presented in this paper. COMET is an experiment at J-PARC, Japan, which will search for neutrinoless conversion of muons into electrons in the field of an aluminum nucleus (⁠μ–e conversion, μ−N→e−N⁠); a lepton flavor-violating process. The experimental sensitivity goal for this process in the Phase-I experiment is 3.1×10−15⁠, or 90% upper limit of a branching ratio of 7×10−15⁠, which is a factor of 100 improvement over the existing limit. The expected number of background events is 0.032. To achieve the target sensitivity and background level, the 3.2 kW 8 GeV proton beam from J-PARC will be used. Two types of detectors, CyDet and StrECAL, will be used for detecting the μ–e conversion events, and for measuring the beam-related background events in view of the Phase-II experiment, respectively. Results from simulation on signal and background estimations are also described.

Journal article

Nakazawa Y, Fujii Y, Gillies E, Hamada E, Igarashi Y, Lee M, Moritsu M, Matsuda Y, Miyazaki Y, Nakai Y, Natori H, Oishi K, Sato A, Uchida Y, Ueno K, Yamaguchi H, Yeo B, Yoshida H, Zhang Jet al., 2020, Radiation hardness study for the COMET Phase-I electronics, Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, Vol: 955, Pages: 1-7, ISSN: 0168-9002

Radiation damage on front-end readout and trigger electronics is an important issue in the COMET Phase-I experiment at J-PARC, which plans to search for the neutrinoless transition of a muon to an electron. To produce an intense muon beam, a high-power proton beam impinges on a graphite target, resulting in a high-radiation environment. We require radiation tolerance to a total dose of 1.0 kGy and 1 MeV equivalent neutron fluence of 1.0 x 10'12 neq cm-2 including a safety factor of 5 over the duration of the physics measurement. The use of commercially-available electronics components which have high radiation tolerance, if such components can be secured, is desirable in such an environment. The radiation hardness of commercial electronic components has been evaluated in gamma-ray and neutron irradiation tests. As results of these tests, voltage regulators, ADCs, DACs, and several other components were found to have enough tolerance to both gamma-ray and neutron irradiation at the level we require.

Journal article

Abe K, Akutsu R, Ali A, Alt C, Amey J, Andreopoulos C, Anthony L, Antonova M, Aoki S, Ariga A, Ashida Y, Atkin ET, Awataguchi Y, Azuma Y, Ban S, Barbi M, Barker GJ, Barr G, Barry C, Batkiewicz-Kwasniak M, Beloshapkin A, Bench F, Berardi V, Berkman S, Berner RM, Berns L, Bhadra S, Bienstock S, Blondel A, Bolognesi S, Bordoni S, Bourguille B, Boyd SB, Brailsford D, Bravar A, Bronner C, Avanzini MB, Calcutt J, Calland RG, Campbell T, Cao S, Cartwright SL, Castillo R, Catanesi MG, Cervera A, Chappell A, Checchia C, Cherdack D, Chikuma N, Christodoulou G, Coleman J, Collazuol G, Cook L, Coplowe D, Cudd A, Dabrowska A, De Rosa G, Dealtry T, Denner PF, Dennis SR, Densham C, Di Lodovico F, Dokania N, Dolan S, Drapier O, Duffy KE, Dumarchez J, Dunne P, Eklund L, Emery-Schrenk S, Ereditato A, Fernandez P, Feusels T, Finch AJ, Fiorentini GA, Fiorillo G, Francois C, Friend M, Fujii Y, Fujita R, Fukuda D, Fukuda R, Fukuda Y, Gameil K, Garcia A, Giganti C, Gizzarelli F, Golan T, Gonin M, Gorin A, Guigue M, Hadley DR, Haegel L, Haigh JT, Hamacher-Baumann P, Hansen D, Harada J, Hartz M, Hasegawa T, Hastings NC, Hayashino T, Hayato Y, Hillairet A, Hiraki T, Hiramoto A, Hirota S, Hogan M, Holeczek J, Van NTH, Hosomi F, Huang K, Iacob F, Ichikawa AK, Ikeda M, Imber J, Inoue T, Insler J, Intonti RA, Ishida T, Ishii T, Ishitsuka M, Iwai E, Iwamoto K, Izmaylov A, Jamieson B, Jenkins SJ, Jesus-Valls C, Jiang M, Johnson S, Jonsson P, Jung CK, Kabirnezhad M, Kaboth AC, Kajita T, Kakuno H, Kameda J, Karlen D, Kataoka Y, Katori T, Kato Y, Kearns E, Khabibullin M, Khotjantsev A, Kim H, Kim J, King S, Kisiel J, Knight A, Knox A, Kobayashi T, Koch L, Koga T, Koller PP, Konaka A, Kormos LL, Koshio Y, Kowalik K, Kubo H, Kudenko Y, Kukita N, Kurjata R, Kutter T, Kuze M, Labarga L, Lagoda J, Lamont I, Lamoureux M, Lasorak P, Laveder M, Lawe M, Licciardi M, Lindner T, Liptak ZJ, Litchfield RP, Liu SL, Li X, Longhin A, Lopez JP, Lou T, Ludovici L, Lu X, Lux T, Machado LN, Magaletti L, Mahn K, Malek Met al., 2020, Measurement of the muon neutrino charged-current single pi(+) production on hydrocarbon using the T2K off-axis near detector ND280, Physical Review D: Particles, Fields, Gravitation and Cosmology, Vol: 101, ISSN: 1550-2368

We report the measurements of the single and double differential cross section of muon neutrino charged-current interactions on carbon with a single positively charged pion in the final state at the T2K off-axis near detector using 5.56×1020 protons on target. The analysis uses data control samples for the background subtraction and the cross section signal, defined as a single negatively charged muon and a single positively charged pion exiting from the target nucleus, is extracted using an unfolding method. The model-dependent cross section, integrated over the T2K off-axis neutrino beam spectrum peaking at 0.6 GeV, is measured to be σ=(11.76±0.44(stat)±2.39(syst))×10−40  cm2 nucleon−1. Various differential cross sections are measured, including the first measurement of the Adler angles for single charged pion production in neutrino interactions with heavy nuclei target.

Journal article

Abe K, Akutsu R, Ali A, Alt C, Andreopoulos C, Anthony L, Antonova M, Aoki S, Ariga A, Ashida Y, Atkin ET, Awataguchi Y, Ban S, Barbi M, Barker GJ, Barr G, Barry C, Batkiewicz-Kwasniak M, Beloshapkin A, Bench F, Berardi V, Berkman S, Berns L, Bhadra S, Bienstock S, Blondel A, Bolognesi S, Bourguille B, Boyd SB, Brailsford D, Bravar A, Berguno DB, Bronner C, Bubak A, Avanzini MB, Calcutt J, Campbell T, Cao S, Cartwright SL, Catanesi MG, Cervera A, Chappell A, Checchia C, Cherdack D, Chikuma N, Christodoulou G, Coleman J, Collazuol G, Cook L, Coplowe D, Cudd A, Dabrowska A, De Rosa G, Dealtry T, Denner PF, Dennis SR, Densham C, Di Lodovico F, Dokania N, Dolan S, Drapier O, Dumarchez J, Dunne P, Eklund L, Emery-Schrenk S, Ereditato A, Fernandez P, Feusels T, Finch AJ, Fiorentini GA, Fiorillo G, Francois C, Friend M, Fujii Y, Fujita R, Fukuda D, Fukuda R, Fukuda Y, Gameil K, Giganti C, Golan T, Gonin M, Gorin A, Guigue M, Hadley DR, Haigh JT, Hamacher-Baumann P, Hartz M, Hasegawa T, Hastings NC, Hayashino T, Hayato Y, Hiramoto A, Hogan M, Holeczek J, Hong Van NT, Iacob F, Ichikawa AK, Ikeda M, Ishida T, Ishii T, Ishitsuka M, Iwamoto K, Izmaylov A, Jamieson B, Jenkins SJ, Jesus-Valls C, Jiang M, Johnson S, Jonsson P, Jung CK, Kabirnezhad M, Kaboth AC, Kajita T, Kakuno H, Kameda J, Karlen D, Kasetti SP, Kataoka Y, Katori T, Kato Y, Kearns E, Khabibullin M, Khotjantsev A, Kikawa T, Kim H, Kim J, King S, Kisiel J, Knight A, Knox A, Kobayashi T, Koch L, Koga T, Konaka A, Kormos LL, Koshio Y, Kowalik K, Kubo H, Kudenko Y, Kukita N, Kuribayashi S, Kurjata R, Kutter T, Kuze M, Labarga L, Lagoda J, Lamoureux M, Laveder M, Lawe M, Licciardi M, Lindner T, Litchfield RP, Liu SL, Li X, Longhin A, Ludovici L, Lu X, Lux T, Machado LN, Magaletti L, Mahn K, Malek M, Manly S, Maret L, Marino AD, Martin JF, Maruyama T, Matsubara T, Matsushita K, Matveev V, Mavrokoridis K, Mazzucato E, McCarthy M, McCauley N, McFarland KS, McGrew C, Mefodiev A, Metelko C, Mezzetto M, Minamino A, Mineev Oet al., 2019, Measurement of neutrino and antineutrino neutral-current quasielasticlike interactions on oxygen by detecting nuclear deexcitation gamma rays, Physical Review D: Particles, Fields, Gravitation and Cosmology, Vol: 100, Pages: 1-19, ISSN: 1550-2368

Neutrino- and antineutrino-oxygen neutral-current quasielasticlike interactions are measured at Super-Kamiokande using nuclear deexcitation γ rays to identify signal-like interactions in data from a 14.94(16.35)×1020 protons-on-target exposure of the T2K neutrino (antineutrino) beam. The measured flux-averaged cross sections on oxygen nuclei are ⟨σν−NCQE⟩=1.70±0.17(stat.)+0.51−0.38(syst.)×10−38  cm2/oxygen with a flux-averaged energy of 0.82 GeV and ⟨σ¯ν−NCQE⟩=0.98±0.16(stat.)+0.26−0.19(syst.)×10−38  cm2/oxygen with a flux-averaged energy of 0.68 GeV, for neutrinos and antineutrinos, respectively. These results are the most precise to date, and the antineutrino result is the first cross section measurement of this channel. They are compared with various theoretical predictions. The impact on evaluation of backgrounds to searches for supernova relic neutrinos at present and future water Cherenkov detectors is also discussed.

Journal article

Hagiwara K, Abe K, Bronner C, Hayato Y, Ikeda M, Ito H, Kameda J, Kataoka Y, Kato Y, Kishimoto Y, Marti L, Miura M, Moriyama S, Mochizuki T, Nakahata M, Nakajima Y, Nakayama S, Okada T, Okamoto K, Orii A, Pronost G, Sekiya H, Shiozawa M, Sonoda Y, Takeda A, Takenaka A, Tanaka H, Yano T, Akutsu R, Kajita T, Okumura K, Wang R, Xia J, Bravo-Berguño D, Labarga L, Fernandez P, Blaszczyk FDM, Kearns E, Raaf JL, Stone JL, Wan L, Wester T, Bian J, Griskevich NJ, Kropp WR, Locke S, Mine S, Smy MB, Sobel HW, Takhistov V, Weatherly P, Ganezer KS, Hill J, Kim JY, Lim IT, Park RG, Bodur B, Scholberg K, Walter CW, Coffani A, Drapier O, Gonin M, Mueller TA, Paganini P, Ishizuka T, Nakamura T, Jang JS, Learned JG, Matsuno S, Litchfield RP, Sztuc AA, Uchida Y, Berardi V, Calabria NF, Catanesi MG, Radicioni E, Rosa GD, Collazuol G, Iacob F, Ludovici L, Nishimura Y, Cao S, Friend M, Hasegawa T, Ishida T, Kobayashi T, Nakadaira T, Nakamura K, Oyama Y, Sakashita K, Sekiguchi T, Tsukamoto T, Hasegawa M, Isobe Y, Miyabe H, Nakano Y, Shiozawa T, Sugimoto T, Suzuki AT, Takeuchi Y, Ali A, Ashida Y, Hirota S, Jiang M, Kikawa T, Mori M, Nakamura KE, Nakaya T, Wendell RA, Anthony LHV, McCauley N, Pritchard A, Tsui KM, Fukuda Y, Itow Y, Niwa T, Taani M, Tsukada M, Mijakowski P, Frankiewicz K, Jung CK, Vilela C, Wilking MJ, Yanagisawa C, Fukuda D, Harada M, Horai T, Ishino H, Ito S, Koshio Y, Sakuda M, Takahira Y, Xu C, Kuno Y, Cook L, Simpson C, Wark D, Lodovico FD, Sedgwick SM, Richards B, Zsoldos S, Kim SB, Thiesse M, Thompson L, Okazawa H, Choi Y, Nishijima K, Koshiba M, Yokoyama M, Goldsack A, Martens K, Quilain B, Suzuki Y, Vagins MR, Kuze M, Tanaka M, Yoshida T, Ishitsuka M, Matsumoto R, Ohta K, Martin JF, Nantais CM, Tanaka HA, Towstego T, Hartz M, Konaka A, Perio PD, Chen S, Jamieson B, Walker J, Minamino A, Okamoto K, Pintaudi Get al., 2019, Search for astronomical neutrinos from blazar TXS 0506+056 in super-kamiokande, The Astrophysical Journal: an international review of astronomy and astronomical physics, Vol: 887, Pages: 1-7, ISSN: 0004-637X

We report a search for astronomical neutrinos in the energy region from several GeV to TeV in the direction of the blazar TXS 0506+056 using the Super-Kamiokande detector following the detection of a 100 TeV neutrinos from the same location by the IceCube collaboration. Using Super-Kamiokande neutrino data across several data samples observed from 1996 April to 2018 February we have searched for both a total excess above known backgrounds across the entire period as well as localized excesses on smaller timescales in that interval. No significant excess nor significant variation in the observed event rate are found in the blazar direction. Upper limits are placed on the electron- and muon-neutrino fluxes at the 90% confidence level as 6.0 × 10−7 and 4.5 × 10−7–9.3 × 10−10 [erg cm−2 s−1], respectively.

Journal article

Simpson C, Abe K, Bronner C, Hayato Y, Ikeda M, Ito H, Iyogi K, Kameda J, Kataoka Y, Kato Y, Kishimoto Y, Marti L, Miura M, Moriyama S, Mochizuki T, Nakahata M, Nakajima Y, Nakayama S, Okada T, Okamoto K, Orii A, Pronost G, Sekiya H, Shiozawa M, Sonoda Y, Takeda A, Takenaka A, Tanaka H, Yano T, Akutsu R, Kajita T, Okumura K, Wang R, Xia J, Bravo-Berguno D, Labarga L, Fernandez P, Blaszczyk FDM, Kachulis C, Kearns E, Raaf JL, Stone JL, Wan L, Wester T, Sussman S, Berkman S, Bian J, Griskevich NJ, Kropp WR, Locke S, Mine S, Smy MB, Sobel HW, Takhistov V, Weatherly P, Ganezer KS, Hill J, Kim JY, Lim IT, Park RG, Bodur B, Scholberg K, Walter CW, Coffani A, Drapier O, Gonin M, Imber J, Mueller TA, Paganini P, Ishizuka T, Nakamura T, Jang JS, Choi K, Learned JG, Matsuno S, Litchfield RP, Sztuc AA, Uchida Y, Wascko MO, Berardi V, Calabria NF, Catanesi MG, Intonti RA, Radicioni E, De Rosa G, Collazuol G, Iacob F, Ludovici L, Nishimura Y, Cao S, Friend M, Hasegawa T, Ishida T, Kobayashi T, Nakadaira T, Nakamura K, Oyama Y, Sakashita K, Sekiguchi T, Tsukamoto T, Abe KE, Hasegawa M, Isobe Y, Miyabe H, Nakano Y, Shiozawa T, Sugimoto T, Suzuki AT, Takeuchi Y, Ali A, Ashida Y, Hayashino T, Hirota S, Jiang M, Kikawa T, Mori M, Nakamura KE, Nakaya T, Wendell RA, Anthony LH, McCauley N, Pritchard A, Tsui KM, Fukuda Y, Itow Y, Murrase M, Niwa T, Taani M, Tsukada M, Mijakowski P, Frankiewicz K, Jung CK, Li X, Palomino JL, Santucci G, Vilela C, Wilking MJ, Yanagisawa C, Fukuda D, Harada M, Hagiwara K, Horai T, Ishino H, Ito S, Koshio Y, Sakuda M, Takahira Y, Xu C, Kuno Y, Cook L, Wark D, Di Lodovico F, Sedgwick SM, Richards B, Zsoldos S, Kim SB, Tacik R, Thiesse M, Thompson L, Okazawa H, Choi Y, Nishijima K, Koshiba M, Yokoyama M, Goldsack A, Martens K, Murdoch M, Quilain B, Suzuki Y, Vagins MR, Kuze M, Okajima Y, Tanaka M, Yoshida T, Ishitsuka M, Matsumoto R, Ohta K, Martin JF, Nantais CM, Tanaka HA, Towstego T, Hartz M, Konaka A, de Perio P, Chen S, Jamieson B, Walker J, Minamino Aet al., 2019, Sensitivity of super-kamiokande with gadolinium to low energy antineutrinos from pre-supernova emission, The Astrophysical Journal: an international review of astronomy and astronomical physics, Vol: 885, Pages: 1-14, ISSN: 0004-637X

Supernova detection is a major objective of the Super-Kamiokande (SK) experiment. In the next stage of SK (SK-Gd), gadolinium (Gd) sulfate will be added to the detector, which will improve the ability of the detector to identify neutrons. A core-collapse supernova (CCSN) will be preceded by an increasing flux of neutrinos and antineutrinos, from thermal and weak nuclear processes in the star, over a timescale of hours; some of which may be detected at SK-Gd. This could provide an early warning of an imminent CCSN, hours earlier than the detection of the neutrinos from core collapse. Electron antineutrino detection will rely on inverse beta decay events below the usual analysis energy threshold of SK, so Gd loading is vital to reduce backgrounds while maximizing detection efficiency. Assuming normal neutrino mass ordering, more than 200 events could be detected in the final 12 hr before core collapse for a 15–25 solar mass star at around 200 pc, which is representative of the nearest red supergiant to Earth, α-Ori (Betelgeuse). At a statistical false alarm rate of 1 per century, detection could be up to 10 hr before core collapse, and a pre-supernova star could be detected by SK-Gd up to 600 pc away. A pre-supernova alert could be provided to the astrophysics community following gadolinium loading.

Journal article

Abe K, Akutsu R, Ali A, Andreopoulos C, Anthony L, Antonova M, Aoki S, Ariga A, Ashida Y, Awataguchi Y, Azuma Y, Ban S, Barbi M, Barker GJ, Barr G, Barry C, Batkiewicz-Kwasniak M, Bench F, Berardi V, Berkman S, Berner RM, Berns L, Bhadra S, Bienstock S, Blondel A, Bolognesi S, Bourguille B, Boyd SB, Brailsford D, Bravar A, Bronner C, Avanzini MB, Calcutt J, Campbell T, Cao S, Cartwright SL, Catanesi MG, Cervera A, Chappell A, Checchia C, Cherdack D, Chikuma N, Christodoulou G, Coleman J, Collazuol G, Coplowe D, Cudd A, Dabrowska A, De Rosa G, Dealtry T, Denner PF, Dennis SR, Densham C, Di Lodovico F, Dokania N, Dolan S, Drapier O, Duffy KE, Dumarchez J, Dunne P, Emery-Schrenk S, Ereditato A, Fernandez P, Feusels T, Finch AJ, Fiorentini GA, Fiorillo G, Francois C, Friend M, Fujii Y, Fujita R, Fukuda D, Fukuda Y, Gameil K, Giganti C, Gizzarelli F, Golan T, Gonin M, Hadley DR, Haegel L, Haigh JT, Hamacher-Baumann P, Hartz M, Hasegawa T, Hastings NC, Hayashino T, Hayato Y, Hiramoto A, Hogan M, Holeczek J, Van NTH, Hosomi F, Iacob F, Ichikawa AK, Ikeda M, Inoue T, Intonti RA, Ishida T, Ishii T, Ishitsuka M, Iwamoto K, Izmaylov A, Jamieson B, Jesus C, Jiang M, Johnson S, Jonsson P, Jung CK, Kabirnezhad M, Kaboth AC, Kajita T, Kakuno H, Kameda J, Karlen D, Katori T, Kato Y, Kearns E, Khabibullin M, Khotjantsev A, Kim H, Kim J, King S, Kisiel J, Knight A, Knox A, Kobayashi T, Koch L, Koga T, Koller PP, Konaka A, Kormos LL, Koshio Y, Kowalik K, Kubo H, Kudenko Y, Kurjata R, Kutter T, Kuze M, Labarga L, Lagoda J, Lamoureux M, Lasorak P, Laveder M, Lawe M, Licciardi M, Lindner T, Liptak ZJ, Litchfield RP, Li X, Longhin A, Lopez JP, Lou T, Ludovici L, Lu X, Lux T, Magaletti L, Mahn K, Malek M, Manly S, Maret L, Marino AD, Martin JF, Martins P, Maruyama T, Matsubara T, Matveev V, Mavrokoridis K, Ma WY, Mazzucato E, McCarthy M, McCauley N, McFarland KS, McGrew C, Mefodiev A, Metelko C, Mezzetto M, Minamino A, Mineev O, Mine S, Miura M, Bueno LM, Moriyama S, Morrison J, Mueller TAet al., 2019, Search for heavy neutrinos with the T2K near detector ND280, Physical Review D: Particles, Fields, Gravitation and Cosmology, Vol: 100, ISSN: 1550-2368

This paper reports on the search for heavy neutrinos with masses in the range 140<MN<493  MeV/c2 using the off-axis near detector ND280 of the T2K experiment. These particles can be produced from kaon decays in the standard neutrino beam and then subsequently decay in ND280. The decay modes under consideration are N→ℓ±απ∓ and N→ℓ+αℓ−β(−)ν(α,β=e,μ). A search for such events has been made using the Time Projection Chambers of ND280, where the background has been reduced to less than two events in the current dataset in all channels. No excess has been observed in the signal region. A combined Bayesian statistical approach has been applied to extract upper limits on the mixing elements of heavy neutrinos to electron-, muon- and tau- flavored currents (U2e, U2μ, U2τ) as a function of the heavy neutrino mass, e.g., U2e<10−9 at 90% C.L. for a mass of 390  MeV/c2. These constraints are competitive with previous experiments.

Journal article

Abe K, Akutsu R, Ali A, Andreopoulos C, Anthony L, Antonova M, Aoki S, Ariga A, Ashida Y, Awataguchi Y, Azuma Y, Ban S, Barbi M, Barker GJ, Barr G, Barry C, Batkiewicz-Kwasniak M, Bench F, Berardi V, Berkman S, Berner RM, Berns L, Bhadra S, Bienstock S, Blondel A, Bolognesi S, Bourguille B, Boyd SB, Brailsford D, Bravar A, Bronner C, Avanzini MB, Calcutt J, Campbell T, Cao S, Cartwright SL, Catanesi MG, Cervera A, Chappell A, Checchia C, Cherdack D, Chikuma N, Christodoulou G, Coleman J, Collazuol G, Coplowe D, Cudd A, Dabrowska A, De Rosa G, Dealtry T, Denner PF, Dennis SR, Densham C, Di Lodovico F, Dokania N, Dolan S, Drapier O, Duffy KE, Dumarchez J, Dunne P, Emery-Schrenk S, Ereditato A, Fernandez P, Feusels T, Finch AJ, Fiorentini GA, Fiorillo G, Francois C, Friend M, Fujii Y, Fujita R, Fukuda D, Fukuda Y, Gameil K, Giganti C, Gizzarelli F, Golan T, Gonin M, Hadley DR, Haigh JT, Hamacher-Baumann P, Hartz M, Hasegawa T, Hastings NC, Hayashino T, Hayato Y, Hiramoto A, Hogan M, Holeczek J, Hong Van NT, Hosomi F, Ichikawa AK, Ikeda M, Inoue T, Intonti RA, Ishida T, Ishii T, Ishitsuka M, Iwamoto K, Izmaylov A, Jamieson B, Jesus-Valls C, Jiang M, Johnson S, Jonsson P, Jung CK, Kabirnezhad M, Kaboth AC, Kajita T, Kakuno H, Kameda J, Karlen D, Katori T, Kato Y, Kearns E, Khabibullin M, Khotjantsev A, Kim H, Kim J, King S, Kisiel J, Knight A, Knox A, Kobayashi T, Koch L, Koga T, Konaka A, Kormos LL, Koshio Y, Kowalik K, Kubo H, Kudenko Y, Kurjata R, Kutter T, Kuze M, Labarga L, Lagoda J, Lamoureux M, Lasorak P, Laveder M, Lawe M, Licciardi M, Lindner T, Litchfield RP, Li X, Longhin A, Lopez JP, Lou T, Ludovici L, Lu X, Lux T, Magaletti L, Mahn K, Malek M, Manly S, Maret L, Marino AD, Martin JF, Martins P, Maruyama T, Matsubara T, Matveev V, Mavrokoridis K, Ma WY, Mazzucato E, McCarthy M, McCauley N, McFarland KS, McGrew C, Mefodiev A, Metelko C, Mezzetto M, Minamino A, Mineev O, Mine S, Miura M, Moriyama S, Morrison J, Mueller TA, Murphy S, Nagai Y, Nakadaira T, Nakahatet al., 2019, Measurement of the muon neutrino charged-current cross sections on water, hydrocarbon and iron, and their ratios, with the T2K on-axis detectors, Progress of Theoretical and Experimental Physics, Vol: 2019, Pages: 1-30, ISSN: 0033-068X

We report a measurement of the flux-integrated νμ charged-current cross sections on water, hydrocarbon, and iron in the T2K on-axis neutrino beam with a mean neutrino energy of 1.5 GeV. The measured cross sections on water, hydrocarbon, and iron are σH2OCC=(0.840±0.010(stat.)+0.10−0.08(syst.))×10−38cm2/nucleon, σCHCC=(0.817±0.007(stat.)+0.11−0.08(syst.))×10−38cm2/nucleon, and σFeCC=(0.859±0.003(stat.)+0.12−0.10(syst.))×10−38cm2/nucleon, respectively, for a restricted phase space of induced muons: θμ<45∘ and pμ>0.4 GeV/c in the laboratory frame. The measured cross section ratios are σH2OCC/σCHCC=1.028±0.016(stat.)±0.053(syst.)⁠, σFeCC/σH2OCC=1.023±0.012(stat.)±0.058(syst.)⁠, and σFeCC/σCHCC=1.049±0.010(stat.)±0.043(syst.)⁠. These results, with an unprecedented precision for the measurements of neutrino cross sections on water in the studied energy region, show good agreement with the current neutrino interaction models used in the T2K oscillation analyses.

Journal article

Abe K, Akutsu R, Ali A, Andreopoulos C, Anthony L, Antonova M, Aoki S, Ariga A, Ashida Y, Awataguchi Y, Azuma Y, Ban S, Barbi M, Barker GJ, Barr G, Barry C, Batkiewicz-Kwasniak M, Bench F, Berardi V, Berkman S, Berner RM, Berns L, Bhadra S, Bienstock S, Blondel A, Bolognesi S, Bourguille B, Boyd SB, Brailsford D, Bravar A, Bronner C, Avanzini MB, Calcutt J, Campbell T, Cao S, Cartwright SL, Catanesi MG, Cervera A, Chappell A, Checchia C, Cherdack D, Chikuma N, Christodoulou G, Coleman J, Collazuol G, Coplowe D, Cudd A, Dabrowska A, Rosa GD, Dealtry T, Denner PF, Dennis SR, Densham C, Lodovico FD, Dokania N, Dolan S, Drapier O, Duffy KE, Dumarchez J, Dunne P, Emery-Schrenk S, Ereditato A, Fernandez P, Feusels T, Finch AJ, Fiorentini GA, Fiorillo G, Francois C, Friend M, Fujii Y, Fujita R, Fukuda D, Fukuda Y, Gameil K, Giganti C, Gizzarelli F, Golan T, Gonin M, Hadley DR, Haigh JT, Hamacher-Baumann P, Hartz M, Hasegawa T, Hastings NC, Hayashino T, Hayato Y, Hiramoto A, Hogan M, Holeczek J, Van NTH, Hosomi F, Ichikawa AK, Ikeda M, Inoue T, Intonti RA, Ishida T, Ishii T, Ishitsuka M, Iwamoto K, Izmaylov A, Jamieson B, Jesus C, Jiang M, Johnson S, Jonsson P, Jung CK, Kabirnezhad M, Kaboth AC, Kajita T, Kakuno H, Kameda J, Karlen D, Katori T, Kato Y, Kearns E, Khabibullin M, Khotjantsev A, Kim H, Kim J, King S, Kisiel J, Knight A, Knox A, Kobayashi T, Koch L, Koga T, Konaka A, Kormos LL, Koshio Y, Kowalik K, Kubo H, Kudenko Y, Kurjata R, Kutter T, Kuze M, Labarga L, Lagoda J, Lamoureux M, Lasorak P, Laveder M, Lawe M, Licciardi M, Lindner T, Litchfield RP, Li X, Longhin A, Lopez JP, Lou T, Ludovici L, Lu X, Lux T, Magaletti L, Mahn K, Malek M, Manly S, Maret L, Marino AD, Martin JF, Martins P, Maruyama T, Matsubara T, Matveev V, Mavrokoridis K, Ma WY, Mazzucato E, McCarthy M, McCauley N, McFarland KS, McGrew C, Mefodiev A, Metelko C, Mezzetto M, Minamino A, Mineev O, Mine S, Miura M, Moriyama S, Morrison J, Mueller TA, Murphy S, Nagai Y, Nakadaira T, Nakahata M, Nakajimaet al., 2019, Search for neutral-current induced single photon production at the ND280 near detector in T2K, Journal of Physics G: Nuclear and Particle Physics, Vol: 46, ISSN: 0954-3899

Neutrino neutral-current (NC) induced single photon production is a sub-leading order process for accelerator-based neutrino beam experiments including T2K. It is, however, an important process to understand because it is a background for electron (anti)neutrino appearance oscillation experiments. Here, we performed the first search of this process below 1 GeV using the fine-grained detector at the T2K ND280 off-axis near detector. By reconstructing single photon kinematics from electron–positron pairs, we achieved 95% pure gamma ray sample from $5.738\times {10}^{20}$ protons-on-targets neutrino mode data. We do not find positive evidence of NC induced single photon production in this sample. We set the model-dependent upper limit on the cross-section for this process, at $0.114\times {10}^{-38}$ cm2 (90% C.L.) per nucleon, using the J-PARC off-axis neutrino beam with an average energy of $\left\langle {E}_{\nu }\right\rangle \sim 0.6$ GeV. This is the first limit on this process below 1 GeV which is important for current and future oscillation experiments looking for electron neutrino appearance oscillation signals.

Journal article

Jiang M, Abe K, Bronner C, Hayato Y, Ikeda M, Iyogi K, Kameda J, Kato Y, Kishimoto Y, Marti LL, Miura M, Moriyama S, Mochizuki T, Nakahata M, Nakajima Y, Nakano Y, Nakayama S, Okada T, Okamoto K, Orii A, Pronost G, Sekiya H, Shiozawa M, Sonoda Y, Takeda A, Takenaka A, Tanaka H, Yano T, Akutsu R, Kajita T, Nishimura Y, Okumura K, Wang R, Xia J, Labarga L, Fernandez P, Blaszczyk FDM, Kachulis C, Kearns E, Raaf JL, Stone JL, Sussman S, Berkman S, Bian J, Griskevich NJ, Kropp WR, Locke S, Mine S, Weatherly P, Smy MB, Sobel HW, Takhistov V, Ganezer KS, Hill J, Kim JY, Lim IT, Park RG, Bodur B, Scholberg K, Walter CW, Gonin M, Imber J, Mueller TA, Ishizuka T, Nakamura T, Jang JS, Choi K, Learned JG, Matsuno S, Litchfield RP, Uchida Y, Wascko MO, Calabria NF, Catanesi MG, Intonti RA, Radicioni E, De Rosa G, Ali A, Collazuol G, Iacob F, Ludovici L, Cao S, Friend M, Hasegawa T, Ishida T, Kobayashi T, Nakadaira T, Nakamura K, Oyama Y, Sakashita K, Sekiguchi T, Tsukamoto T, Abe KE, Hasegawa M, Isobe Y, Miyabe H, Sugimoto T, Suzuki AT, Takeuchi Y, Ashida Y, Hayashino T, Hirota S, Kikawa T, Mori M, Nakamura KE, Nakaya T, Wendell RA, Anthony LHV, McCauley N, Pritchard A, Tsui KM, Fukuda Y, Itow Y, Murrase M, Mijakowski P, Frankiewicz K, Jung CK, Li X, Palomino JL, Santucci G, Vilela C, Wilking MJ, Yanagisawa C, Fukuda D, Hagiwara K, Ishino H, Ito S, Koshio Y, Sakuda M, Takahira Y, Xu C, Kuno Y, Simpson C, Wark D, Di Lodovico F, Richards B, Molina Sedgwick S, Tacik R, Kim SB, Thiesse M, Thompson L, Okazawa H, Choi Y, Nishijima K, Koshiba M, Yokoyama M, Goldsack A, Martens K, Murdoch M, Quilain B, Suzuki Y, Vagins MR, Kuze M, Okajima Y, Yoshida T, Ishitsuka M, Martin JF, Nantais CM, Tanaka HA, Towstego T, Hartz M, Konaka A, de Perio P, Chen S, Wan L, Minamino Aet al., 2019, Atmospheric neutrino oscillation analysis with improved event reconstruction in Super-Kamiokande IV, Progress of Theoretical and Experimental Physics, Vol: 2019, ISSN: 2050-3911

A new event reconstruction algorithm based on a maximum likelihood method has been developed for Super-Kamiokande. Its improved kinematic and particle identification capabilities enable the analysis of atmospheric neutrino data in a detector volume 32% larger than previous analyses and increase the sensitivity to the neutrino mass hierarchy. Analysis of a 253.9 kton⋅year exposure of the Super-Kamiokande IV atmospheric neutrino data has yielded a weak preference for the normal hierarchy, disfavoring the inverted hierarchy at 74% assuming oscillations at the best fit of the analysis.

Journal article

Abe K, Akutsu R, Ali A, Andreopoulos C, Anthony L, Antonova M, Aoki S, Ariga A, Ashida Y, Awataguchi Y, Azuma Y, Ban S, Barbi M, Barker GJ, Barr G, Barry C, Batkiewicz-Kwasniak M, Bench F, Berardi V, Berkman S, Berner RM, Berns L, Bhadra S, Bienstock S, Blondel A, Bolognesi S, Bourguille B, Boyd SB, Brailsford D, Bravar A, Bronner C, Avanzini MB, Calcutt J, Campbell T, Cao S, Cartwright SL, Catanesi MG, Cervera A, Chappell A, Checchia C, Cherdack D, Chikuma N, Christodoulou G, Coleman J, Collazuol G, Coplowe D, Cudd A, Dabrowska A, De Rosa G, Dealtry T, Denner PF, Dennis SR, Densham C, Di Lodovico F, Dokania N, Dolan S, Drapier O, Duffy KE, Dumarchez J, Dunne P, Emery-Schrenk S, Ereditato A, Fernandez P, Feusels T, Finch AJ, Fiorentini GA, Fiorillo G, Francois C, Friend M, Fujii Y, Fujita R, Fukuda D, Fukuda Y, Gameil K, Giganti C, Gizzarelli F, Golan T, Gonin M, Hadley DR, Haigh JT, Hamacher-Baumann P, Hartz M, Hasegawa T, Hastings NC, Hayashino T, Hayato Y, Hiramoto A, Hogan M, Holeczek J, Van NTH, Hosomi F, Iacob F, Ichikawa AK, Ikeda M, Inoue T, Intonti RA, Ishida T, Ishii T, Ishitsuka M, Iwamoto K, Izmaylov A, Jamieson B, Jesus C, Jiang M, Johnson S, Jonsson P, Jung CK, Kabirnezhad M, Kaboth AC, Kajita T, Kakuno H, Kameda J, Karlen D, Katori T, Kato Y, Kearns E, Khabibullin M, Khotjantsev A, Kim H, Kim J, King S, Kisiel J, Knight A, Knox A, Kobayashi T, Koch L, Koga T, Konaka A, Kormos LL, Koshio Y, Kowalik K, Kubo H, Kudenko Y, Kurjata R, Kutter T, Kuze M, Labarga L, Lagoda J, Lamoureux M, Lasorak P, Laveder M, Lawe M, Licciardi M, Lindner T, Litchfield RP, Li X, Longhin A, Lopez JP, Lou T, Ludovici L, Lu X, Lux T, Magaletti L, Mahn K, Malek M, Manly S, Maret L, Marino AD, Martin JF, Martins P, Maruyama T, Matsubara T, Matveev V, Mavrokoridis K, Ma WY, Mazzucato E, McCarthy M, McCauley N, McFarland KS, McGrew C, Mefodiev A, Metelko C, Mezzetto M, Minamino A, Mineev O, Mine S, Miura M, Bueno LM, Moriyama S, Morrison J, Mueller TA, Murphy S, Nagai Y, Nakadaira Tet al., 2019, Search for light sterile neutrinos with the T2K far detector Super-Kamiokande at a baseline of 295 km, Physical Review D: Particles, Fields, Gravitation and Cosmology, Vol: 99, ISSN: 1550-2368

We perform a search for light sterile neutrinos using the data from the T2K far detector at a baseline of 295 km, with an exposure of 14.7(7.6)×1020 protons on target in neutrino (antineutrino) mode. A selection of neutral-current interaction samples is also used to enhance the sensitivity to sterile mixing. No evidence of sterile neutrino mixing in the 3+1 model was found from a simultaneous fit to the charged-current muon, electron and neutral-current neutrino samples. We set the most stringent limit on the sterile oscillation amplitude sin2θ24 for the sterile neutrino mass splitting Δm241<3×10−3  eV2/c4.

Journal article

Wan L, Abe K, Bronner C, Hayato Y, Ikeda M, Iyogi K, Kameda J, Kato Y, Kishimoto Y, Marti L, Miura M, Moriyama S, Mochizuki T, Nakahata M, Nakajima Y, Nakano Y, Nakayama S, Okada T, Okamoto K, Orii A, Pronost G, Sekiya H, Shiozawa M, Sonoda Y, Takeda A, Takenaka A, Tanaka H, Yano T, Akutsu R, Kajita T, Nishimura Y, Okumura K, Wang R, Xia J, Labarga L, Fernandez P, Blaszczyk FDM, Kachulis C, Kearns E, Raaf JL, Stone JL, Sussman S, Berkman S, Bian J, Griskevich NJ, Kropp WR, Locke S, Mine S, Weatherly P, Smy MB, Sobel HW, Takhistov V, Ganezer KS, Hill J, Kim JY, Lim IT, Park RG, Bodur B, Scholberg K, Walter CW, Gonin M, Imber J, Mueller TA, Ishizuka T, Nakamura T, Jang JS, Choi K, Learned JG, Matsuno S, Litchfield RP, Uchida Y, Wascko MO, Calabria NF, Catanesi MG, Intonti RA, Radicioni E, De Rosa G, Ali A, Collazuol G, Iacob F, Ludovici L, Cao S, Friend M, Hasegawa T, Ishida T, Kobayashi T, Nakadaira T, Nakamura K, Oyama Y, Sakashita K, Sekiguchi T, Tsukamoto T, Abe KE, Hasegawa M, Isobe Y, Miyabe H, Sugimoto T, Suzuki AT, Takeuchi Y, Ashida Y, Hayashino T, Hirota S, Jiang M, Kikawa T, Mori M, Nakamura KE, Nakaya T, Wendell RA, Anthony LHV, McCauley N, Pritchard A, Tsui KM, Fukuda Y, Itow Y, Murrase M, Mijakowski P, Frankiewicz K, Jung CK, Li X, Palomino JL, Santucci G, Vilela C, Wilking MJ, Yanagisawa C, Fukuda D, Hagiwara K, Ishino H, Ito S, Koshio Y, Sakuda M, Takahira Y, Xu C, Kuno Y, Simpson C, Wark D, Di Lodovico F, Richards B, Sedgwick SM, Tacik R, Kim SB, Thiesse M, Thompson L, Okazawa H, Choi Y, Nishijima K, Koshiba M, Yokoyama M, Goldsack A, Martens K, Murdoch M, Quilain B, Suzuki Y, Vagins MR, Kuze M, Okajima Y, Yoshida T, Ishitsuka M, Martin JF, Nantais CM, Tanaka HA, Towstego T, Hartz M, Konaka A, de Perio P, Chen S, Minamino Aet al., 2019, Measurement of the neutrino-oxygen neutral-current quasielastic cross section using atmospheric neutrinos at Super-Kamiokande, Physical Review D, Vol: 99, ISSN: 2470-0010

Neutral current (NC) interactions of atmospheric neutrinos on oxygen form one of the major backgrounds in the search for supernova relic neutrinos with water-based Cherenkov detectors. The NC channel is dominated by neutrino quasielastic (NCQE) scattering off nucleons inside 16O nuclei. In this paper we report the first measurement of NCQE cross section using atmospheric neutrinos at Super-Kamiokande (SK). The measurement used 2,778 live days of SK-IV data with a fiducial volume of 22.5 kiloton water. Within the visible energy window of 7.5–29.5 MeV, we observed 117 events compared to the expected 71.9 NCQE signal and 53.1 background events. Weighted by the atmospheric neutrino spectrum from 160 MeV to 10 GeV, the flux averaged NCQE cross section is measured to be (1.01±0.17(stat.)+0.78−0.30(sys.))×10−38  cm2.

Journal article

Abe K, Akutsu R, Amey J, Andreopoulos C, Anthony L, Antonova M, Aoki S, Ariga A, Ashida Y, Azuma Y, Ban S, Barbi M, Barker GJ, Barr G, Barry C, Batkiewicz M, Bench F, Ali A, Berardi V, Berkman S, Berner RM, Berns L, Bhadra S, Bienstock S, Blondel A, Bolognesi S, Bourguille B, Boyd SB, Brailsford D, Bravar A, Bronner C, Avanzini MB, Calcutt J, Campbell T, Cao S, Cartwright SL, Catanesi MG, Cervera A, Chappell A, Checchia C, Cherdack D, Chilcuma N, Christodoulou G, Coleman J, Collazuol G, Coplowe D, Cudd A, Dabrowska A, De Rosa G, Dealtry T, Denner PF, Dennis SR, Densham C, Di Lodovico F, Dokania N, Dolan S, Drapier O, Duffy KE, Dumarchez J, Dunne P, Emery-Schrenk S, Ereditato A, Fernandez P, Feusels T, Finch AJ, Fiorentini GA, Fiorilloi G, Francois C, Friend M, Fujiii Y, Fujita R, Fukuda D, Fukuda Y, Gameil K, Giganti C, Gizzarelli F, Golan T, Gonin M, Hadley DR, Haegel L, Haigh JT, Hamacher-Baumann P, Hansen D, Harada J, Hartz M, Hasegawa T, Hastings NC, Hayashino T, Hayato Y, Hiramoto A, Hogan M, Holeczek J, Hosomi F, Ichikawa AK, Ikeda M, Imber J, Inoue T, Intonti RA, Ishida T, Ishii T, Ishitsuka M, Iwamoto K, Izmaylov A, Jamieson B, Jiang M, Johnson S, Jonsson P, Jung CK, Kabirnezhad M, Kaboth AC, Kajita T, Kakuno H, Kameda J, Karlen D, Katori T, Kato Y, Kearns E, Khabibullin M, Khotjantsev A, Kim J, King S, Kisiel J, Knight A, Knox A, Kobayashi T, Koch L, Koga T, Koller PP, Konaka A, Kormos LL, Koshio Y, Kowailk K, Kubo H, Kudenko Y, Kurjata R, Kutter T, Kuze M, Labarga L, Lagoda J, Lasorak P, Laveder M, Lawe M, Licciarai M, Lindner T, Liptak ZJ, Litchfield RP, Li X, Longhin A, Lou T, Ludovici L, Lu X, Magalettii L, Mahn K, Malek M, Manly S, Maret L, Marino AD, Martin JF, Martins P, Maruyama T, Matsubara T, Matveev V, Mavrokoridis K, Ma WY, Mazzucato E, McCarthy M, McCauley N, McFarland KS, McGrew C, Mefodiev A, Kim H, Lamoureux M, Lopez JP, Metelko C, Mezzetto M, Minamino A, Mineev O, Mine S, Missert A, Miura M, Moriyama S, Morrison J, Mueller TA, Murphy S, Naget al., 2018, Search for CP violation in neutrino and antineutrino oscillations by the T2K experiment with 2.2 x 10(21) protons on target, Physical Review Letters, Vol: 121, ISSN: 0031-9007

The T2K experiment measures muon neutrino disappearance and electron neutrino appearance in accelerator-produced neutrino and antineutrino beams. With an exposure of 14.7(7.6)×1020 protons on target in the neutrino (antineutrino) mode, 89 νe candidates and seven anti-νe candidates are observed, while 67.5 and 9.0 are expected for δCP=0 and normal mass ordering. The obtained 2σconfidence interval for the CP-violating phase, δCP, does not include the CP-conserving cases (δCP=0, π). The best-fit values of other parameters are sin2θ23=0.526+0.032−0.036 and Δm232=2.463+0.071−0.070×10−3  eV2/c4.

Journal article

Li Z, Abe K, Bronner C, Hayato Y, Ikeda M, Iyogi K, Kameda J, Kato Y, Kishimoto Y, Marti L, Miura M, Moriyama S, Nakahata M, Nakajima Y, Nakano Y, Nakayama S, Orii A, Pronost G, Sekiya H, Shiozawa M, Sonoda Y, Takeda A, Takenaka A, Tanaka H, Tasaka S, Tomura T, Akutsu R, Kajita T, Nishimura Y, Okumura K, Tsui KM, Fernandez P, Labarga L, Blaszczyk FDM, Gustafson J, Kachulis C, Kearns E, Raaf JL, Stone JL, Sulak LR, Berkman S, Tobayama S, Elnimr M, Kropp WR, Locke S, Mine S, Weatherly P, Smy MB, Sobel HW, Takhistov V, Ganezer KS, Hill J, Kim JY, Lim IT, Park RG, Himmel A, O'Sullivan E, Scholberg K, Walter CW, Ishizuka T, Nakamura T, Jang JS, Choi K, Learned JG, Matsuno S, Smith SN, Amey J, Litchfield RP, Ma WY, Uchida Y, Wascko MO, Cao S, Friend M, Hasegawa T, Ishida T, Ishii T, Kobayashi T, Nakadaira T, Nakamura K, Oyama Y, Sakashita K, Sekiguchi T, Tsukamoto T, Abe KE, Hasegawa M, Suzuki AT, Takeuchi Y, Yano T, Hayashino T, Hiraki T, Hirota S, Huang K, Jiang M, Mori M, Nakamura KE, Nakaya T, Patel ND, Wendell RA, Anthony LHV, McCauley N, Pritchard A, Fukuda Y, Itow Y, Murase M, Muto F, Mijakowski P, Frankiewicz K, Jung CK, Li X, Palomino JL, Santucci G, Vilela C, Wilking MJ, Yanagisawa C, Yang G, Ito S, Fukuda D, Ishino H, Kibayashi A, Koshio Y, Nagata H, Sakuda M, Xu C, Kuno Y, Wark D, Di Lodovico F, Richards B, Sedgwick SM, Tacik R, Kim SB, Cole A, Thompson L, Okazawa H, Choi Y, Ito K, Nishijima K, Koshiba M, Suda Y, Yokoyama M, Calland RG, Hartz M, Martens K, Murdoch M, Quilain B, Simpson C, Suzuki Y, Vagins MR, Hamabe D, Kuze M, Okajima Y, Yoshida T, Ishitsuka M, Martin JF, Nantais CM, Tanaka HA, Towstego T, Konaka A, Chen S, Wan L, Zhang Y, Minamino A, Wilkes RJet al., 2018, Measurement of the tau neutrino cross section in atmospheric neutrino oscillations with Super-Kamiokande, PHYSICAL REVIEW D, Vol: 98, ISSN: 2470-0010

Using 5326 days of atmospheric neutrino data, a search for atmospheric tau neutrino appearance has been performed in the Super-Kamiokande experiment. Super-Kamiokande measures the tau normalization to be 1.47±0.32 under the assumption of normal neutrino hierarchy, relative to the expectation of unity with neutrino oscillation. The result excludes the hypothesis of no-tau appearance with a significance level of 4.6σ. The inclusive charged-current tau neutrino cross section averaged by the tau neutrino flux at Super-Kamiokande is measured to be (0.94±0.20)×10−38  cm2. The measurement is consistent with the Standard Model prediction, agreeing to within 1.5σ.

Journal article

This data is extracted from the Web of Science and reproduced under a licence from Thomson Reuters. You may not copy or re-distribute this data in whole or in part without the written consent of the Science business of Thomson Reuters.

Request URL: http://wlsprd.imperial.ac.uk:80/respub/WEB-INF/jsp/search-html.jsp Request URI: /respub/WEB-INF/jsp/search-html.jsp Query String: respub-action=search.html&id=00414300&limit=30&person=true