skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Supersymmetric dark matter and lepton flavor violation

Abstract

We study lepton flavor-violating (LFV) processes within a supersymmetric type-I seesaw framework with flavor-blind universal boundary conditions, properly accounting for the effect of the neutrino sector on the dark matter relic abundance. We consider several possibilities for the neutrino Yukawa coupling matrix and show that in regions of SUSY parameter space that yield the correct neutralino relic density, LFV rates can differ from naive estimates by up to 2 orders of magnitude. Contrary to common belief, we find that current LFV limits do not exclude neutrino Yukawa couplings larger than top Yukawa couplings. We introduce the ISAJET-M program that was used for the computations.

Authors:
 [1]; ; ;  [2]
  1. Department of Physics, University of Wisconsin, Madison, Wisconsin 53706 (United States)
  2. Department of Physics and Astronomy, University of Kansas, Lawrence, Kansas 66045 (United States)
Publication Date:
OSTI Identifier:
21325285
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. D, Particles Fields; Journal Volume: 80; Journal Issue: 7; Other Information: DOI: 10.1103/PhysRevD.80.076004; (c) 2009 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; BOUNDARY CONDITIONS; COUPLING; DENSITY; FLAVOR MODEL; NEUTRINOS; NONLUMINOUS MATTER; SIMULATION; SUPERSYMMETRY; YUKAWA POTENTIAL

Citation Formats

Barger, Vernon, Marfatia, Danny, Mustafayev, Azar, and Soleimani, Ali. Supersymmetric dark matter and lepton flavor violation. United States: N. p., 2009. Web. doi:10.1103/PHYSREVD.80.076004.
Barger, Vernon, Marfatia, Danny, Mustafayev, Azar, & Soleimani, Ali. Supersymmetric dark matter and lepton flavor violation. United States. doi:10.1103/PHYSREVD.80.076004.
Barger, Vernon, Marfatia, Danny, Mustafayev, Azar, and Soleimani, Ali. 2009. "Supersymmetric dark matter and lepton flavor violation". United States. doi:10.1103/PHYSREVD.80.076004.
@article{osti_21325285,
title = {Supersymmetric dark matter and lepton flavor violation},
author = {Barger, Vernon and Marfatia, Danny and Mustafayev, Azar and Soleimani, Ali},
abstractNote = {We study lepton flavor-violating (LFV) processes within a supersymmetric type-I seesaw framework with flavor-blind universal boundary conditions, properly accounting for the effect of the neutrino sector on the dark matter relic abundance. We consider several possibilities for the neutrino Yukawa coupling matrix and show that in regions of SUSY parameter space that yield the correct neutralino relic density, LFV rates can differ from naive estimates by up to 2 orders of magnitude. Contrary to common belief, we find that current LFV limits do not exclude neutrino Yukawa couplings larger than top Yukawa couplings. We introduce the ISAJET-M program that was used for the computations.},
doi = {10.1103/PHYSREVD.80.076004},
journal = {Physical Review. D, Particles Fields},
number = 7,
volume = 80,
place = {United States},
year = 2009,
month =
}
  • We reexamine the prospects for the detection of Higgs-mediated lepton flavor violation at LHC, at a photon collider and in {tau} decays such as {tau}{yields}{mu}{eta}, {tau}{yields}{mu}{gamma}. We allow for the presence of a large, model independent, source of lepton flavor violation in the slepton mass matrix in the {tau}-{mu} sector by the mass insertion approximation and constrain the parameter space using the {tau} lepton flavor violating decays together with the B-mesons physics observables, the anomalous magnetic moment of the muon, and the dark matter relic density. We further impose the exclusion limit on spin-independent neutralino-nucleon scattering from CDMS and themore » CDF limits from direct search of the heavy neutral Higgs at the TEVATRON. We find rates probably too small to be observed at future experiments if models have to accommodate for the relic density measured by WMAP and explain the (g-2){sub {mu}}anomaly: better prospects are found if these two constraints are applied only as upper bounds. The spin-independent neutralino-nucleon cross section in the studied constrained parameter space is just below the present CDMS limit and the running XENON100 experiment will cover the region of the parameter space where the lightest neutralino has large gaugino-Higgsino mixing.« less
  • We study a supersymmetric version of the seesaw mechanism type III. The model consists of the minimal supersymmetric extension of the standard model particle content plus three copies of 24 superfields. The fermionic part of the SU(2) triplet contained in the 24 is responsible for the type-III seesaw, which is used to explain the observed neutrino masses and mixings. Complete copies of 24 are introduced to maintain gauge coupling unification. These additional states change the beta functions of the gauge couplings above the seesaw scale. Using minimal Supergravity boundary conditions, we calculate the resulting supersymmetric mass spectra at the electroweakmore » scale using full 2-loop renormalization group equations. We show that the resulting spectrum can be quite different compared to the usual minimal Supergravity spectrum. We discuss how this might be used to obtain information on the seesaw scale from mass measurements. Constraints on the model space due to limits on lepton flavour violating decays are discussed. The main constraints come from the bounds on {mu}{yields}e{gamma} but there are also regions where the decay {tau}{yields}{mu}{gamma} gives stronger constraints. We also calculate the regions allowed by the dark matter constraint. For the sake of completeness, we compare our results with those for the supersymmetric seesaw type II and, to some extent, with type I.« less
  • We study gravitino dark matter and slow gravitino decays in supersymmetric theories with broken R-parity. It turns out that for the model parameters that may give rise to viable radiative neutrino masses, and visible R-violating signatures in colliders, gravitinos are cosmologically stable and can be good dark matter candidates. On the contrary, the decays of the Next-to-Lightest Supersymmetric Particle are fast, and can be easily reconciled with Big Bang Nucleosynthesis. For the interesting range of parameters, observable lepton flavour violation is also to be expected, with rates that are strongly dependent from the flavour structure of the R-violating operators, andmore » with distinct correlations that should be distinguishable in the coming generation of experiments.« less
  • We analyze the complementarity between lepton flavor violation (LFV) and LHC experiments in probing the supersymmetric (SUSY) grand unified theories (GUT) when neutrinos get a mass via the seesaw mechanism. Our analysis is performed in an SO(10) framework, where at least one neutrino Yukawa coupling is necessarily as large as the top Yukawa coupling. Our study thoroughly takes into account the whole renormalization group running, including the GUT and the right-handed neutrino mass scales, as well as the running of the observable neutrino spectrum. We find that the upcoming (MEG, SuperKEKB) and future (PRISM/PRIME, super flavor factory) LFV experiments willmore » be able to test such SUSY framework for SUSY masses to be explored at the LHC and, in some cases, even beyond the LHC sensitivity reach.« less
  • Various lepton-flavor-violating (LFV) processes in the supersymmetric standard model with right-handed neutrino supermultiplets are investigated in detail. It is shown that large LFV rates are obtained when tan{beta} is large. In the case where the mixing matrix in the lepton sector has a similar structure as the Kobayashi-Maskawa matrix and the third-generation Yukawa coupling is as large as that of the top quark, the branching ratios can be as large as {ital B}({mu}{r_arrow}{ital e}{gamma}){approx_equal}10{sup {minus}11} and {ital B}({tau}{r_arrow}{mu}{gamma}){approx_equal}10{sup {minus}7}, which are within the reach of future experiments. If we assume a large mixing angle solution to the atmospheric neutrino problem,more » the rate for the process {tau}{r_arrow}{mu}{gamma} becomes larger. We also discuss the difference between our case and the case of the minimal SU(5) grand unified theory. {copyright} {ital 1996 The American Physical Society.}« less