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Related papers: Exact Cross Sections for the Neutralino WIMP Pair-…

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Coannihilation processes provide an important additional mechanism for reducing the density of stable relics in the Universe. In the case of the stable lightest neutralino of the MSSM, and in particular the Constrained MSSM (CMSSM), the…

High Energy Physics - Phenomenology · Physics 2009-11-07 Takeshi Nihei , Leszek Roszkowski , Roberto Ruiz de Austri

From the relic density measurement by WMAP the WIMP annihilation cross section can be determined in a model independent way. If the WIMPS are postulated to be the neutralinos of Supersymmetry, then only a limited region of the…

High Energy Physics - Phenomenology · Physics 2011-09-13 W. de Boer , M. Herold , C. Sander , V. Zhukov

We compute analytically the tree-level annihilation rates of a collection of non-relativistic neutralino and chargino two-particle states in the general MSSM, including the previously unknown off-diagonal rates. The results are…

High Energy Physics - Phenomenology · Physics 2014-01-09 M. Beneke , C. Hellmann , P. Ruiz-Femenia

We present exact analytic cross sections for all neutralino-neutralino coannihilations into two-body tree level final states. These expressions allow the calculation of important contributions to the neutralino relic abundance over large…

High Energy Physics - Phenomenology · Physics 2014-11-17 A. Birkedal-Hansen , E. Jeong

The cosmological significance of the neutralino sector is studied for a class of models in which electroweak symmetry breaking is seeded by a gauge singlet. Extensive use is made of the renormalisation group equations to significantly…

High Energy Physics - Phenomenology · Physics 2011-02-16 S. A. Abel , S. Sarkar , I. B. Whittingham

This paper concludes the presentation of the non-relativistic effective field theory formalism designed to calculate the radiative corrections that enhance the pair-annihilation cross sections of slowly moving neutralinos and charginos…

High Energy Physics - Phenomenology · Physics 2014-11-26 M. Beneke , C. Hellmann , P. Ruiz-Femenia

We compute the neutralino relic density in the minimal supersymmetric standard model by using exact expressions for the neutralino annihilation cross section into all tree-level final states, including all contributions and interference…

High Energy Physics - Phenomenology · Physics 2010-02-03 Takeshi Nihei , Leszek Roszkowski , Roberto Ruiz de Austri

This paper is a continuation of an earlier work (arXiv:1210.7928) which computed analytically the tree-level annihilation rates of a collection of non-relativistic neutralino and chargino two-particle states in the general MSSM. Here we…

High Energy Physics - Phenomenology · Physics 2014-01-09 C. Hellmann , P. Ruiz-Femenia

Evaluating the relic density of dark matter is an interesting possibility to constrain the parameter space of new physics models. However, this calculation is affected by several sources of uncertainty. On the particle physics side,…

High Energy Physics - Phenomenology · Physics 2010-12-01 Björn Herrmann

We enlarge our set of supersymmetric models and update accelerator constraints in our precise calculation of the relic density of the lightest neutralino, which includes relativistic Boltzmann averaging, subthreshold and resonant…

High Energy Physics - Phenomenology · Physics 2007-05-23 Paolo Gondolo , Joakim Edsjo

We compute the annihilation cross-section of two neutralinos at rest into two photons, which is of importance for the indirect detection of neutralino dark matter in the galactic halo through a quasi-monochromatic gamma-ray line. We include…

High Energy Physics - Phenomenology · Physics 2008-11-26 Z. Bern , P. Gondolo , M. Perelstein

The parameters of the Minimal Supersymmetric Standard Model appear to require uncomfortably precise adjustment in order to reconcile the electroweak symmetry breaking scale with the lower mass limits on a neutral Higgs scalar boson. This…

High Energy Physics - Phenomenology · Physics 2008-11-26 Stephen P. Martin

We study pair annihilations of the neutralino dark matter in the minimal supersymmetric standard model with CP violation. We consider the case that the higgsino mass and the trilinear scalar couplings have CP-violating phases of order…

High Energy Physics - Phenomenology · Physics 2009-11-11 Takeshi Nihei

We compute the full O(alpha_s) supersymmetric QCD corrections for neutralino-stop co-annihilation into electroweak gauge and Higgs bosons in the Minimal Supersymmetric Standard Model (MSSM). We show that these annihilation channels are…

High Energy Physics - Phenomenology · Physics 2013-04-09 J. Harz , B. Herrmann , M. Klasen , K. Kovarik , Q. Le Boulc'h

We evaluate the relic density of the lightest neutralino, the lightest supersymmetric particle, in the Minimal Supersymmetric extension of the Standard Model (MSSM). For the first time, we include all coannihilation processes between…

High Energy Physics - Phenomenology · Physics 2008-11-26 J. Edsjo , P. Gondolo

We compute one-loop corrections to the annihilation of non--relativistic particles $\chi$ due to the exchange of a (gauge or Higgs) boson $\phi$ with mass $\mu$ in the initial state. In the limit $m_\chi \gg \mu$ this leads to the…

High Energy Physics - Phenomenology · Physics 2010-05-25 M. Drees , J. M. Kim , K. I. Nagao

The extracted value of the relic density has reached the few per-cent level precision. One can therefore no longer content oneself with calculations of this observable where the annihilation processes are computed at tree-level, especially…

High Energy Physics - Phenomenology · Physics 2013-05-29 Fawzi Boudjema , Guillaume Drieu La Rochelle , Suchita Kulkarni

We present an improved partial wave analysis of the dominant LSP annihilation channel to a fermion-antifermion pair which avoids the non-relativistic expansion being therefore applicable near thresholds and poles. The method we develop…

High Energy Physics - Phenomenology · Physics 2014-11-17 M. Argyrou , A. B. Lahanas , D. V. Nanopoulos , V. C. Spanos

We investigate, if the cosmic ray positron fraction, as reported by the HEAT and AMS collaborations, is compatible with the annihilation of neutralinos in the supergravity inspired Constrained Minimal Supersymmetric Model (CMSSM), thus…

Astrophysics · Physics 2009-11-07 W. de Boer , C. Sander , M. Horn , D. Kazakov

A full one-loop calculation of neutralino S-wave annihilation into the $Z\gamma$ final state is performed in the minimal supersymmetric extension of the Standard Model. This process, like the similar one with two photons in the final state,…

High Energy Physics - Phenomenology · Physics 2010-11-30 P. Ullio , L. Bergstrom
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