The positron excess as a smoking gun for dynamical dark matter?

Keith R Dienes, Jason Kumar, Brooks Thomas

Research output: Chapter in Book/Report/Conference proceedingConference contribution

1 Citation (Scopus)

Abstract

One of the most puzzling aspects of recent data from the AMS-02 experiment is an apparent rise in the cosmic-ray positron fraction as a function of energy. This feature is observed out to energies of approximately 350 GeV. One explanation of these results interprets the extra positrons as arising from the decays of dark-matter particles. This in turn typically requires that such particles have rather heavy TeV-scale masses and not undergo simple two-body decays to leptons. In this talk, by contrast, we show that Dynamical Dark Matter (DDM) can not only match existing AMS-02 data on the positron excess, but also accomplish this feat with significantly lighter dark-matter constituents undergoing simple two-body decays to leptons. We also demonstrate that the Dynamical Dark Matter framework makes a fairly robust prediction that the positron fraction should level off and then remain roughly constant out to approximately 1 TeV, without experiencing any sharp downturns. Thus, if we interpret the positron excess in terms of decaying dark matter, the existence of a plateau in the positron fraction at energies less than 1 TeV may be taken as a "smoking gun" of Dynamical Dark Matter.

Original languageEnglish (US)
Title of host publicationAIP Conference Proceedings
PublisherAmerican Institute of Physics Inc.
Pages22-33
Number of pages12
Volume1604
ISBN (Print)9780735412385
DOIs
StatePublished - 2014
EventWorkshop on Dark Matter, Neutrino Physics and Astrophysics, CETUP* 2013 and 7th International Conference on Interconnections Between Particle Physics and Cosmology, PPC* 2013 - Lead/Deadwood, SD, United States
Duration: Jun 24 2013Jul 26 2013

Other

OtherWorkshop on Dark Matter, Neutrino Physics and Astrophysics, CETUP* 2013 and 7th International Conference on Interconnections Between Particle Physics and Cosmology, PPC* 2013
CountryUnited States
CityLead/Deadwood, SD
Period6/24/137/26/13

Fingerprint

positrons
dark matter
Alpha Magnetic Spectrometer
leptons
decay
energy
cosmic rays
plateaus
predictions

Keywords

  • AMS
  • cosmic ray
  • Dynamical Dark Matter
  • flux
  • positron

ASJC Scopus subject areas

  • Physics and Astronomy(all)

Cite this

Dienes, K. R., Kumar, J., & Thomas, B. (2014). The positron excess as a smoking gun for dynamical dark matter? In AIP Conference Proceedings (Vol. 1604, pp. 22-33). American Institute of Physics Inc.. https://doi.org/10.1063/1.4883409

The positron excess as a smoking gun for dynamical dark matter? / Dienes, Keith R; Kumar, Jason; Thomas, Brooks.

AIP Conference Proceedings. Vol. 1604 American Institute of Physics Inc., 2014. p. 22-33.

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Dienes, KR, Kumar, J & Thomas, B 2014, The positron excess as a smoking gun for dynamical dark matter? in AIP Conference Proceedings. vol. 1604, American Institute of Physics Inc., pp. 22-33, Workshop on Dark Matter, Neutrino Physics and Astrophysics, CETUP* 2013 and 7th International Conference on Interconnections Between Particle Physics and Cosmology, PPC* 2013, Lead/Deadwood, SD, United States, 6/24/13. https://doi.org/10.1063/1.4883409
Dienes KR, Kumar J, Thomas B. The positron excess as a smoking gun for dynamical dark matter? In AIP Conference Proceedings. Vol. 1604. American Institute of Physics Inc. 2014. p. 22-33 https://doi.org/10.1063/1.4883409
Dienes, Keith R ; Kumar, Jason ; Thomas, Brooks. / The positron excess as a smoking gun for dynamical dark matter?. AIP Conference Proceedings. Vol. 1604 American Institute of Physics Inc., 2014. pp. 22-33
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