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Title: Towards a supersymmetric description of the Fermi Galactic center excess

Abstract

We attempt to build a model that describes the Fermi galactic gamma-ray excess (FGCE) within a UV-complete Supersymmetric framework; we find this to be highly non-trivial. At the very least a successful Supersymmetric explanation must have several important ingredients in order to fit the data and satisfy other theoretical and experimental constraints. Under the assumption that a single annihilation mediator is responsible for both the observed relic density as well as the FGCE, we show that the requirements are not easily satisfied in many TeV-scale SUSY models, but can be met with some model building effort in the general NMSSM with ~ 10 parameters beyond the MSSM. We find that the data selects a particular region of the parameter space with a mostly singlino lightest Supersymmetric particle and a relatively light CP-odd Higgs boson that acts as the mediator for dark matter annihilation. We study the predictions for various observables within this parameter space, and find that searches for this light CP-odd state at the LHC, as well as searches for the direct detection of dark matter, are likely to be quite challenging. It is possible that a signature could be observed in the flavor sector; however, indirect detection remainsmore » the best probe of this scenario.« less

Authors:
 [1];  [2];  [1];  [1]
  1. SLAC National Accelerator Laboratory, Menlo Park, CA (United States)
  2. Univ. of Florida, Gainesville, FL (United States)
Publication Date:
Research Org.:
SLAC National Accelerator Lab., Menlo Park, CA (United States)
Sponsoring Org.:
USDOE Office of Science (SC)
OSTI Identifier:
1213910
Grant/Contract Number:
AC03-76SF00515
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Journal of High Energy Physics (Online)
Additional Journal Information:
Journal Name: Journal of High Energy Physics (Online); Journal Volume: 2015; Journal Issue: 2; Journal ID: ISSN 1029-8479
Publisher:
Springer Berlin
Country of Publication:
United States
Language:
English
Subject:
79 ASTRONOMY AND ASTROPHYSICS; 72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; Supersymmetry Phenomenology

Citation Formats

Cahill-Rowley, M., Gainer, J. S., Hewett, J. L., and Rizzo, T. G. Towards a supersymmetric description of the Fermi Galactic center excess. United States: N. p., 2015. Web. doi:10.1007/JHEP02(2015)057.
Cahill-Rowley, M., Gainer, J. S., Hewett, J. L., & Rizzo, T. G. Towards a supersymmetric description of the Fermi Galactic center excess. United States. doi:10.1007/JHEP02(2015)057.
Cahill-Rowley, M., Gainer, J. S., Hewett, J. L., and Rizzo, T. G. Tue . "Towards a supersymmetric description of the Fermi Galactic center excess". United States. doi:10.1007/JHEP02(2015)057. https://www.osti.gov/servlets/purl/1213910.
@article{osti_1213910,
title = {Towards a supersymmetric description of the Fermi Galactic center excess},
author = {Cahill-Rowley, M. and Gainer, J. S. and Hewett, J. L. and Rizzo, T. G.},
abstractNote = {We attempt to build a model that describes the Fermi galactic gamma-ray excess (FGCE) within a UV-complete Supersymmetric framework; we find this to be highly non-trivial. At the very least a successful Supersymmetric explanation must have several important ingredients in order to fit the data and satisfy other theoretical and experimental constraints. Under the assumption that a single annihilation mediator is responsible for both the observed relic density as well as the FGCE, we show that the requirements are not easily satisfied in many TeV-scale SUSY models, but can be met with some model building effort in the general NMSSM with ~ 10 parameters beyond the MSSM. We find that the data selects a particular region of the parameter space with a mostly singlino lightest Supersymmetric particle and a relatively light CP-odd Higgs boson that acts as the mediator for dark matter annihilation. We study the predictions for various observables within this parameter space, and find that searches for this light CP-odd state at the LHC, as well as searches for the direct detection of dark matter, are likely to be quite challenging. It is possible that a signature could be observed in the flavor sector; however, indirect detection remains the best probe of this scenario.},
doi = {10.1007/JHEP02(2015)057},
journal = {Journal of High Energy Physics (Online)},
number = 2,
volume = 2015,
place = {United States},
year = {Tue Feb 10 00:00:00 EST 2015},
month = {Tue Feb 10 00:00:00 EST 2015}
}

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Cited by: 36works
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  • Observations with the Fermi Large Area Telescope (LAT) indicate an excess in gamma rays originating from the center of our Galaxy. A possible explanation for this excess is the annihilation of Dark Matter particles. We have investigated the annihilation of neutralinos as Dark Matter candidates within the phenomenological Minimal Supersymmetric Standard Model (pMSSM). An iterative particle filter approach was used to search for solutions within the pMSSM. We found solutions that are consistent with astroparticle physics and collider experiments, and provide a fit to the energy spectrum of the excess. The neutralino is a Bino/Higgsino or Bino/Wino/Higgsino mixture with amore » mass in the range 84–92 GeV or 87–97 GeV annihilating into W bosons. A third solutions is found for a neutralino of mass 174–187 GeV annihilating into top quarks. The best solutions yield a Dark Matter relic density 0.06« less
  • Observations with the Fermi Large Area Telescope (LAT) indicate an excess in gamma rays originating from the center of our Galaxy. A possible explanation for this excess is the annihilation of Dark Matter particles. We have investigated the annihilation of neutralinos as Dark Matter candidates within the phenomenological Minimal Supersymmetric Standard Model (pMSSM) . An iterative particle filter approach was used to search for solutions within the pMSSM . We found solutions that are consistent with astroparticle physics and collider experiments, and provide a fit to the energy spectrum of the excess. The neutralino is a Bino/Higgsino or Bino/Wino/Higgsino mixturemore » with a mass in the range 84–92 GeV or 87–97 GeV annihilating into W bosons. A third solutions is found for a neutralino of mass 174–187 GeV annihilating into top quarks. The best solutions yield a Dark Matter relic density 0.06 < Ω h{sup 2} <0.13. These pMSSM solutions make clear forecasts for LHC, direct and indirect DM detection experiments. If the pMSSM explanation of the excess seen by Fermi-LAT is correct, a DM signal might be discovered soon.« less
  • A spherical-symmetric gamma-ray emission from (the inner region of the Galaxy (at least up to roughly 10° in latitude and longitude)) has been recently identified in Fermi-LAT data, and initially associated to dark matter particle annihilations. Guided by the evidence for a high gas density in the inner kpc of the Galaxy correlated with a very large Supernova rate, and hence with ongoing cosmic-ray acceleration, we investigate instead the possibility of addressing this excess in terms of ordinary cosmic-ray sources and standard steady-state diffusion. We (alter the source term, and consistently the correlated gamma-ray emissions, in the context of amore » template-fitting analysis. We focus on a region of interest (ROI) defined as: |l| < 20°; 2° < |b| < 20°, with l and b the Galactic longitude and latitude coordinates.) We analyze in detail the overall goodness of the fit of our framework, and perform a detailed direct comparison against data examining profiles in different directions. Remarkably, the test statistic of the fit related to our scenario turns out to be as good as the Dark Matter one in the ROI here considered.« less