Imperial College London
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ProfessorArttuRajantie

Faculty of Natural Sciences, Department of Physics

Professor of Theoretical Physics
 
 
 
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Contact

 

+44 (0)20 7594 7835a.rajantie Website CV

 
 
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Location

 

605Huxley BuildingSouth Kensington Campus

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Summary

 

Publications

Citation

BibTex format

@article{Karam:2020:10.1007/JHEP11(2020)153,
author = {Karam, A and Markkanen, T and Marzola, L and Nurmi, S and Raidal, M and Rajantie, A},
doi = {10.1007/JHEP11(2020)153},
journal = {The Journal of High Energy Physics},
title = {Novel mechanism for primordial perturbations in minimal extensions of the Standard Model},
url = {http://dx.doi.org/10.1007/JHEP11(2020)153},
volume = {2020},
year = {2020}
}
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RIS format (EndNote, RefMan)

TY  - JOUR
AB  - We demonstrate that light spectator fields in their equilibrium can source sizeable CMB anisotropies through modulated reheating even in the absence of direct couplings to the inflaton. The effect arises when the phase space of the inflaton decay is modulated by the spectator which generates masses for the decay products. We call the mechanism indirect modulation and using the stochastic eigenvalue expansion show that it can source perturbations even four orders of magnitude larger than the observed amplitude. Importantly, the indirect mechanism is present in the Standard Model extended with right- handed neutrinos. For a minimally coupled Higgs boson this leads to a novel lower bound on the quartic coupling and constrains the neutrino Yukawas below unity.
AU  - Karam,A
AU  - Markkanen,T
AU  - Marzola,L
AU  - Nurmi,S
AU  - Raidal,M
AU  - Rajantie,A
DO  - 10.1007/JHEP11(2020)153
PY  - 2020///
SN  - 1029-8479
TI  - Novel mechanism for primordial perturbations in minimal extensions of the Standard Model
T2  - The Journal of High Energy Physics
UR  - http://dx.doi.org/10.1007/JHEP11(2020)153
UR  - http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcApp=PARTNER_APP&SrcAuth=LinksAMR&KeyUT=WOS:000595812200005&DestLinkType=FullRecord&DestApp=ALL_WOS&UsrCustomerID=1ba7043ffcc86c417c072aa74d649202
UR  - https://link.springer.com/article/10.1007/JHEP11(2020)153
UR  - http://hdl.handle.net/10044/1/96438
VL  - 2020
ER  -
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