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Title: A novel approach to derive halo-independent limits on dark matter properties

Abstract

We propose a method that allows to place an upper limit on the dark matter elastic scattering cross section with nucleons which is independent of the velocity distribution. Our approach combines null results from direct detection experiments with indirect searches at neutrino telescopes, and goes beyond previous attempts to remove astrophysical uncertainties in that it directly constrains the particle physics properties of the dark matter. The resulting halo-independent upper limits on the scattering cross section of dark matter are remarkably strong and reach σ{sub SI}{sup p}≲10{sup −43} (10{sup −42}) cm{sup 2} and σ{sub SD}{sup p}≲10{sup −37} (3×10{sup −37}) cm{sup 2}, for dark matter particles of m{sub DM}∼1 TeV annihilating into W{sup +}W{sup −} (bb-bar), assuming ρ{sub loc}=0.3 GeV/cm{sup 3}.

Authors:
 [1]; ;  [2]
  1. Physics Department and McDonnell Center for the Space Sciences,Washington University in Saint Louis,1 Brookings Drive - CB 1105, St Louis, MO 63130 (United States)
  2. Physik-Department T30d, Technische Universität München,James-Franck-Straße, 85748 Garching (Germany)
Publication Date:
Sponsoring Org.:
SCOAP3, CERN, Geneva (Switzerland)
OSTI Identifier:
22458381
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Cosmology and Astroparticle Physics; Journal Volume: 2015; Journal Issue: 09; Other Information: PUBLISHER-ID: JCAP09(2015)052; OAI: oai:repo.scoap3.org:11908; Article funded by SCOAP3. Content from this work may be used under the terms of the Creative Commons Attribution 3.0 License. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; 79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; ASTROPHYSICS; CROSS SECTIONS; ELASTIC SCATTERING; GEV RANGE; NEUTRINO DETECTION; NEUTRINOS; NONLUMINOUS MATTER; NUCLEONS; TELESCOPES; TEV RANGE

Citation Formats

Ferrer, Francesc, Ibarra, Alejandro, and Wild, Sebastian. A novel approach to derive halo-independent limits on dark matter properties. United States: N. p., 2015. Web. doi:10.1088/1475-7516/2015/09/052.
Ferrer, Francesc, Ibarra, Alejandro, & Wild, Sebastian. A novel approach to derive halo-independent limits on dark matter properties. United States. doi:10.1088/1475-7516/2015/09/052.
Ferrer, Francesc, Ibarra, Alejandro, and Wild, Sebastian. 2015. "A novel approach to derive halo-independent limits on dark matter properties". United States. doi:10.1088/1475-7516/2015/09/052.
@article{osti_22458381,
title = {A novel approach to derive halo-independent limits on dark matter properties},
author = {Ferrer, Francesc and Ibarra, Alejandro and Wild, Sebastian},
abstractNote = {We propose a method that allows to place an upper limit on the dark matter elastic scattering cross section with nucleons which is independent of the velocity distribution. Our approach combines null results from direct detection experiments with indirect searches at neutrino telescopes, and goes beyond previous attempts to remove astrophysical uncertainties in that it directly constrains the particle physics properties of the dark matter. The resulting halo-independent upper limits on the scattering cross section of dark matter are remarkably strong and reach σ{sub SI}{sup p}≲10{sup −43} (10{sup −42}) cm{sup 2} and σ{sub SD}{sup p}≲10{sup −37} (3×10{sup −37}) cm{sup 2}, for dark matter particles of m{sub DM}∼1 TeV annihilating into W{sup +}W{sup −} (bb-bar), assuming ρ{sub loc}=0.3 GeV/cm{sup 3}.},
doi = {10.1088/1475-7516/2015/09/052},
journal = {Journal of Cosmology and Astroparticle Physics},
number = 09,
volume = 2015,
place = {United States},
year = 2015,
month = 9
}
  • We propose a method that allows to place an upper limit on the dark matter elastic scattering cross section with nucleons which is independent of the velocity distribution. Our approach combines null results from direct detection experiments with indirect searches at neutrino telescopes, and goes beyond previous attempts to remove astrophysical uncertainties in that it directly constrains the particle physics properties of the dark matter. The resulting halo-independent upper limits on the scattering cross section of dark matter are remarkably strong and reach σ{sub SI}{sup p} ∼< 10{sup −43} (10{sup −42}) cm{sup 2} and σ{sub SD}{sup p} ∼< 10{sup −37} (3× 10{sup −37}) cm{sup 2}, for dark matter particlesmore » of m{sub DM} ∼ 1 TeV annihilating into W{sup +}W{sup −} (b b-bar ), assuming ρ{sub loc}=0.3 GeV/cm{sup 3}.« less
  • Uncertainty in the local dark matter velocity distribution is a key difficulty in the analysis of data from direct detection experiments. Here we propose a new approach for dealing with this uncertainty, which does not involve any assumptions about the structure of the dark matter halo. Given a dark matter model, our method yields the velocity distribution which best describes a set of direct detection data as a finite sum of streams with optimised speeds and densities. The method is conceptually simple and numerically very efficient. We give an explicit example in which the method is applied to determining themore » ratio of proton to neutron couplings of dark matter from a hypothetical set of future data.« less
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  • Here, we implemented a novel technique to perform the collective spectral analysis of sets of multiple gamma-ray point sources using the data collected by the Large Area Telescope onboard the Fermi satellite. The energy spectra of the sources are reconstructed starting from the photon counts and without assuming any spectral model for both the sources and the background. In case of faint sources, upper limits on their fluxes are evaluated with a Bayesian approach. Our analysis technique is very useful when several sources with similar spectral features are studied, such as sources of gamma rays from annihilation of dark mattermore » particles. We also present the results obtained by applying this analysis to a sample of dwarf spheroidal galaxies and to the Milky Way dark matter halo. The analysis of dwarf spheroidal galaxies yields upper limits on the product of the dark matter pair annihilation cross section and the relative velocity of annihilating particles that are well below those predicted by the canonical thermal relic scenario in a mass range from a few GeV to a few tens of GeV for some annihilation channels.« less