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Title: Stop co-annihilation in the minimal supersymmetric standard model revisited

Authors:
; ;
Publication Date:
Sponsoring Org.:
USDOE Office of Science (SC), High Energy Physics (HEP) (SC-25)
OSTI Identifier:
1417071
Grant/Contract Number:
SC0007859
Resource Type:
Journal Article: Published Article
Journal Name:
Physical Review D
Additional Journal Information:
Journal Volume: 97; Journal Issue: 2; Related Information: CHORUS Timestamp: 2018-01-16 10:15:38; Journal ID: ISSN 2470-0010
Publisher:
American Physical Society
Country of Publication:
United States
Language:
English

Citation Formats

Pierce, Aaron, Shah, Nausheen R., and Vogl, Stefan. Stop co-annihilation in the minimal supersymmetric standard model revisited. United States: N. p., 2018. Web. doi:10.1103/PhysRevD.97.023008.
Pierce, Aaron, Shah, Nausheen R., & Vogl, Stefan. Stop co-annihilation in the minimal supersymmetric standard model revisited. United States. doi:10.1103/PhysRevD.97.023008.
Pierce, Aaron, Shah, Nausheen R., and Vogl, Stefan. 2018. "Stop co-annihilation in the minimal supersymmetric standard model revisited". United States. doi:10.1103/PhysRevD.97.023008.
@article{osti_1417071,
title = {Stop co-annihilation in the minimal supersymmetric standard model revisited},
author = {Pierce, Aaron and Shah, Nausheen R. and Vogl, Stefan},
abstractNote = {},
doi = {10.1103/PhysRevD.97.023008},
journal = {Physical Review D},
number = 2,
volume = 97,
place = {United States},
year = 2018,
month = 1
}

Journal Article:
Free Publicly Available Full Text
Publisher's Version of Record at 10.1103/PhysRevD.97.023008

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  • We revisit the one-loop calculation of the annihilation of a pair of the lightest neutralinos into a pair of photons, a pair of gluons and also a Z photon final state. For the latter we have identified a new contribution that may not always be negligible. For all three processes we have conducted a tuned comparison with previous calculations for some characteristic scenarios. The approach to the very heavy Higgsino and W-ino is studied and we argue how the full one-loop calculation should be matched into a more complete treatment that was presented recently for these extreme regimes. We alsomore » give a short description of the code that we exploited for the automatic calculation of one-loop cross sections in the minimal supersymmetric model that could apply, both for observables at the colliders and for astrophysics or relic density calculations. In particular, the automatic treatment of zero Gram determinants which appear in the latter applications is outlined. We also point out how generalized nonlinear gauge-fixing constraints can be exploited.« less
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