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Related papers: Full One-loop Calculation of Neutralino Annihilati…

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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

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 complete 1-loop computation of the processes $(\tchi^0_i \tchi^0_j \leftrightarrow\gamma\gamma, ~ gg)$, for any pair of the four MSSM neutralinos, has been performed for an arbitrary c.m energy. As a first application suitable for Dark…

High Energy Physics - Phenomenology · Physics 2011-07-19 G. J. Gounaris , J. Layssac , P. I. Porfyriadis , F. M. Renard

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…

High Energy Physics - Phenomenology · Physics 2011-07-19 F. Boudjema , A. Semenov , D. Temes

The neutralino pair annihilation into two photons in our galactic halo gives a robust dark matter signal, since it would give a quasi-monotonic gamma ray. This process is radiatively-induced, and the full-one loop calculation was done…

High Energy Physics - Phenomenology · Physics 2009-11-07 Junji Hisano , Sh. Matsumoto , Mihoko M. Nojiri

We calculate the flux of cosmic gamma rays expected {}from the annihilation of neutralinos in the Galactic halo. Our calculation of the annihilation cross section to two photons improves the existing calculations by inclusion of exact…

High Energy Physics - Phenomenology · Physics 2016-09-01 Gerard Jungman , Marc Kamionkowski

We calculate, using unitarity, a lower bound on the branching ratio $\chi\chi\to \gamma\gamma$ and $\chi\chi\to \gamma Z$, where $\chi$ is any halo dark matter particle that has $W^+W^-$ as one of the major annihilation modes. Examples of…

High Energy Physics - Phenomenology · Physics 2010-11-30 L. Bergstrom , J. Kaplan

We calculate one-loop corrections to the decays of the next-to-lightest neutralino $\tilde{\chi}_2^0$ into the lightest neutralino $\tilde{\chi}_1^0$ and two leptons; this includes diagrams where a real photon is emitted. In cases where…

High Energy Physics - Phenomenology · Physics 2010-10-27 Manuel Drees , Wolfgang Hollik , Qingjun Xu

We perform a comprehensive analysis of the decays of charginos and neutralinos in the Minimal Supersymmetric Standard Model where the neutralino $\chi_1^0$ is assumed to be the lightest supersymmetric particle. We focus, in particular, on…

High Energy Physics - Phenomenology · Physics 2009-01-07 A. Djouadi , Y. Mambrini , M. Muhlleitner

We study properties of the lightest neutralino (\chi) and calculate its cosmological relic density in a supersymmetric U(1)' model with a secluded U(1)' breaking sector (the S-model). The lightest neutralino mass is smaller than in the…

High Energy Physics - Phenomenology · Physics 2009-09-15 Vernon Barger , Chung Kao , Paul Langacker , Hye-Sung Lee

We explore the prospects for indirect detection of neutralino dark matter in supersymmetric models with an extended Higgs sector (NMSSM). We compute, for the first time, one-loop amplitudes for NMSSM neutralino pair annihilation into two…

High Energy Physics - Phenomenology · Physics 2008-11-26 Francesc Ferrer , Lawrence M. Krauss , Stefano Profumo

The annihilation cross section of TeV scale dark matter particles $\chi^0$ with electroweak charges into photons is affected by large quantum corrections due to Sudakov logarithms and the Sommerfeld effect. We calculate the semi-inclusive…

High Energy Physics - Phenomenology · Physics 2020-12-17 M. Beneke , A. Broggio , C. Hasner , M. Vollmann

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

Within the minimal supersymmetric extension of the Standard Model, the best fit to the most recent precision-measurement data requires charginos and neutralinos, with dominant Higgsino components and with masses within the reach of LEP1.5…

High Energy Physics - Phenomenology · Physics 2008-11-26 S. Ambrosanio , M. Carena , B. Mele , C. E. M. Wagner

The 1-loop computation of the processes $\tchi_i \tchi_j \to \gamma Z$ 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…

High Energy Physics - Phenomenology · Physics 2009-11-11 Th. Diakonidis , G. J. Gounaris , J. Layssac , P. I. Porfyriadis , F. M. Renard

We study the effect of the MeV-scale asymmetric dark matter annihilation on the effective number of neutrinos $N_{\rm eff}$ at the epoch of the big bang nucleosynthesis. If the asymmetric dark matter $\chi$ couples more strongly to the…

High Energy Physics - Phenomenology · Physics 2016-03-23 Teruyuki Kitabayashi , Yoshihiro Kurosawa

We present a complete calculation of the electroweak one-loop corrections to the relic density within the MSSM framework. In the context of the neutralino as dark matter candidate, we review different scenarios of annihilation and…

High Energy Physics - Phenomenology · Physics 2015-05-14 N. Baro , G. Chalons , Sun Hao

Assuming that the underlying model satisfies some general requirements such as renormalizability and CP conservation, we calculate the non-relativistic one-loop cross section for any self-conjugate dark matter particle annihilating into two…

High Energy Physics - Phenomenology · Physics 2017-10-30 Camilo Garcia-Cely , Andres Rivera

Recent advances in N-body simulations of cold dark matter halos point to a substantial density enhancement near the center. This means that, e.g., the $\gamma$ ray signals from neutralino dark matter annihilations would be significantly…

Astrophysics · Physics 2010-11-30 L. Bergstrom , P. Ullio , J. Buckley

We present a complete 1-loop study of the process $\gamma \gamma \to \tchi^0_i \tchi^0_j$ and the predicted cross section in a $\gamma\gamma$ Linear Collider. A suitable numerical code PLATONlc, valid for any set of real MSSM parameters, is…

High Energy Physics - Phenomenology · Physics 2008-11-26 G. J. Gounaris , J. Layssac , P. I. Porfyriadis , F. M. Renard
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