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Title: Neutralino-neutralino annihilation to {gamma}Z in MSSM

Abstract

The 1-loop computation of the processes {chi}-tilde{sub i}{sup 0}{chi}-tilde{sub j}{sup 0}{yields}{gamma}Z has been performed at an arbitrary c.m. energy for any pair of MSSM neutralinos. As an application suitable for dark matter (DM) searches, the neutralino-neutralino annihilation is studied at the limiting case of vanishing relative velocity, describing the present DM distribution in the galactic halo; and at a relative velocity of about 0.5, determining the neutralino relic density contributions. The most useful situation is obviously for i=j=1, but the case of nonidentical neutralinos may also be useful in some corners of the parameter space. Our results are contained in the FORTRAN code PLATONdmgZ, applying to any set of real MSSM parameters. Numerical results are also presented for a sample of 6 MSSM models, describing the various possible neutralino properties. A comparison with other existing works is also made.

Authors:
; ;  [1]; ;  [2]
  1. Department of Theoretical Physics, Aristotle University of Thessaloniki, Gr-54124, Thessaloniki (Greece)
  2. Laboratoire de Physique Theorique et Astroparticules, UMR 5207, Universite Montpellier II, F-34095 Montpellier Cedex 5 (France)
Publication Date:
OSTI Identifier:
20782787
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. D, Particles Fields; Journal Volume: 73; Journal Issue: 7; Other Information: DOI: 10.1103/PhysRevD.73.073003; (c) 2006 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; ANNIHILATION; COMPARATIVE EVALUATIONS; DISTRIBUTION; NONLUMINOUS MATTER; SPARTICLES; STANDARD MODEL; SUPERSYMMETRY

Citation Formats

Diakonidis, Th., Gounaris, G.J., Porfyriadis, P.I., Layssac, J., and Renard, F. M. Neutralino-neutralino annihilation to {gamma}Z in MSSM. United States: N. p., 2006. Web. doi:10.1103/PHYSREVD.73.073003.
Diakonidis, Th., Gounaris, G.J., Porfyriadis, P.I., Layssac, J., & Renard, F. M. Neutralino-neutralino annihilation to {gamma}Z in MSSM. United States. doi:10.1103/PHYSREVD.73.073003.
Diakonidis, Th., Gounaris, G.J., Porfyriadis, P.I., Layssac, J., and Renard, F. M. Sat . "Neutralino-neutralino annihilation to {gamma}Z in MSSM". United States. doi:10.1103/PHYSREVD.73.073003.
@article{osti_20782787,
title = {Neutralino-neutralino annihilation to {gamma}Z in MSSM},
author = {Diakonidis, Th. and Gounaris, G.J. and Porfyriadis, P.I. and Layssac, J. and Renard, F. M.},
abstractNote = {The 1-loop computation of the processes {chi}-tilde{sub i}{sup 0}{chi}-tilde{sub j}{sup 0}{yields}{gamma}Z has been performed at an arbitrary c.m. energy for any pair of MSSM neutralinos. As an application suitable for dark matter (DM) searches, the neutralino-neutralino annihilation is studied at the limiting case of vanishing relative velocity, describing the present DM distribution in the galactic halo; and at a relative velocity of about 0.5, determining the neutralino relic density contributions. The most useful situation is obviously for i=j=1, but the case of nonidentical neutralinos may also be useful in some corners of the parameter space. Our results are contained in the FORTRAN code PLATONdmgZ, applying to any set of real MSSM parameters. Numerical results are also presented for a sample of 6 MSSM models, describing the various possible neutralino properties. A comparison with other existing works is also made.},
doi = {10.1103/PHYSREVD.73.073003},
journal = {Physical Review. D, Particles Fields},
number = 7,
volume = 73,
place = {United States},
year = {Sat Apr 01 00:00:00 EST 2006},
month = {Sat Apr 01 00:00:00 EST 2006}
}
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