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Related papers: Neutralino annihilation beyond leading order

200 papers

We present a complete calculation of the QCD and SUSY-QCD corrections to neutralino pair annihilation into bottom quark-antiquark pairs through exchange of a pseudoscalar Higgs boson, which is the dominant process in the cosmological…

High Energy Physics - Phenomenology · Physics 2007-09-17 Björn Herrmann

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

What is the upper limit of the mass of the neutralino dark matter whose thermal relic is consistent with the observation? If the neutralino dark matter and colored sparticles are extremely degenerated in mass, with a mass difference less…

High Energy Physics - Phenomenology · Physics 2020-01-07 Hajime Fukuda , Feng Luo , Satoshi Shirai

We calculate the supersymmetric QCD corrections in order $\alpha_s$ to the decays $\squark_i \to q' \chargino_j$ (i,j = 1,2) and $\squark_i \to q \neutralino_k$ (k = 1,...4) within the Minimal Supersymmetric Standard Model. In particular we…

High Energy Physics - Phenomenology · Physics 2011-01-27 S. Kraml , H. Eberl , A. Bartl , W. Majerotto , W. Porod

We describe how the nested soft-collinear subtraction scheme [1] can be used to compute the next-to-next-to-leading order (NNLO) QCD corrections to the production of an arbitrary number of gluonic jets in hadron collisions. We show that the…

High Energy Physics - Phenomenology · Physics 2025-03-20 Federica Devoto , Kirill Melnikov , Raoul Röntsch , Chiara Signorile-Signorile , Davide Maria Tagliabue

The direct detection of neutralino dark matter is analysed in general supergravity scenarios, where non-universal soft scalar and gaugino masses can be present. In particular, the theoretical predictions for the neutralino-nucleon cross…

High Energy Physics - Phenomenology · Physics 2009-11-11 S. Baek , D. G. Cerdeno , Y. G. Kim , P. Ko , C. Munoz

Neutralino as the lightest supersymmetric particle (LSP) is a candidate for supersymmetric dark matter. It is known that coannihilation effects could be important in neutralino relic density calculation. Here we present some results on…

High Energy Physics - Phenomenology · Physics 2009-11-07 Yudi Santoso

We present the first exact and most general neutralino-neutralino annihilation cross sections in the presence of flavor violation. The existing set of calculations in literature do not include flavour violation. These calculations are…

High Energy Physics - Phenomenology · Physics 2015-01-05 V. Suryanarayana Mummidi

The Minimal Supersymmetric Standard Model opens the possibility of electroweak baryogenesis provided that the light scalar top quark (stop) is lighter than the top quark. In addition, the lightest neutralino is an ideal candidate to explain…

High Energy Physics - Phenomenology · Physics 2008-11-26 M. Carena , A. Finch , A. Freitas , C. Milstene , H. Nowak , A. Sopczak

The production and decay of supersymmetric particles is presented. The dependence of the hadro-production cross section for weakly and strongly interacting yields an improvement of derived mass bounds or the measurement of the masses,…

High Energy Physics - Phenomenology · Physics 2007-05-23 Tilman Plehn

We have calculated the full O(alpha_s) supersymmetric QCD corrections to neutralino-stop co-annihilation into electroweak vector and Higgs bosons within the Minimal Supersymmetric Standard Model (MSSM). We performed a parameter study within…

High Energy Physics - Phenomenology · Physics 2013-02-15 J. Harz , B. Herrmann , M. Klasen , K. Kovarik , Q. Le Boulc'h

Decays of the lightest neutralino are studied in $R_p$-violating models, with operators $\lambda^\prime L Q D^c$ and $\lambda L L E^c$ involving third-generation matter fields and with dominant $\lambda^\prime$ and $\lambda$ couplings.…

High Energy Physics - Phenomenology · Physics 2007-05-23 R. M. Godbole

Electron-positron annihilation into hadrons plus an energetic photon from initial state radiation allows the hadronic cross-section to be measured over a wide range of energies. The full next-to-leading order QED corrections for the…

High Energy Physics - Phenomenology · Physics 2011-09-13 G. Rodrigo , H. Czyz , J. H. Kuhn , M. Szopa

We calculate spin-independent and spin-dependent direct detection cross sections of neutralino dark matter at next-to-leading order of QCD. The numerical effects are comparable in size to the uncertainties in the nuclear matrix elements.…

High Energy Physics - Phenomenology · Physics 2017-09-11 M. Klasen , K. Kovarik , S. Schmiemann

Once supersymmetric neutralinos $\tilde{\chi}^0$ are produced copiously at $e^+e^-$ linear colliders, their characteristics can be measured with high precision. In particular, the fundamental parameters in the gaugino/higgsino sector of the…

High Energy Physics - Phenomenology · Physics 2009-11-11 S. Y. Choi , M. Drees , J. Song

The total cross section for top quark pair production close to threshold in e+e- annihilation is investigated. Details are given about the calculation at next-to-next-to-leading logarithmic order. The summation of logarithms leads to a…

High Energy Physics - Phenomenology · Physics 2008-11-26 A. H. Hoang , A. V. Manohar , I. W. Stewart , T. Teubner

We calculate the supersymmetric QCD corrections in order $\alpha_s$ to the cross section $e^+ e^- \to \sq_i \bar\sq_j$ $(i,j = 1, 2)$ within the Minimal Supersymmetric Standard Model. We pay particular attention to the case of the…

High Energy Physics - Phenomenology · Physics 2009-10-28 H. Eberl , A. Bartl , W. Majerotto

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

In supersymmetric models with an unbroken R-symmetry (rather than only R-parity), the neutralinos are Dirac fermions rather than Majorana. In this article, we discuss the phenomenology of neutralino dark matter in such models, including the…

High Energy Physics - Phenomenology · Physics 2013-11-05 Matthew R. Buckley , Dan Hooper , Jason Kumar

The process pp -> top anti-top bottom anti-bottom + X represents a very important background reaction to searches at the LHC, in particular to top anti-top H production where the Higgs boson decays into a bottom anti-bottom pair. A…

High Energy Physics - Phenomenology · Physics 2010-12-09 Axel Bredenstein , Ansgar Denner , Stefan Dittmaier , Stefano Pozzorini