https://doi.org/10.1140/epjc/s10052-014-3224-5
Regular Article - Experimental Physics
Multipole analysis of IceCube data to search for dark matter accumulated in the Galactic halo
IceCube Collaboration
1
III. Physikalisches Institut, RWTH Aachen University, 52056, Aachen, Germany
2
School of Chemistry and Physics, University of Adelaide, Adelaide, SA, 5005, Australia
3
Department of Physics and Astronomy, University of Alaska Anchorage, 3211 Providence Dr., Anchorage, AK, 99508, USA
4
CTSPS, Clark-Atlanta University, Atlanta, GA, 30314, USA
5
School of Physics and Center for Relativistic Astrophysics, Georgia Institute of Technology, Atlanta, GA, 30332, USA
6
Department of Physics, Southern University, Baton Rouge, LA, 70813, USA
7
Department of Physics, University of California, Berkeley, CA, 94720, USA
8
Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, USA
9
Institut für Physik, Humboldt-Universität zu Berlin, 12489, Berlin, Germany
10
Fakultät für Physik und Astronomie, Ruhr-Universität Bochum, 44780, Bochum, Germany
11
Physikalisches Institut, Universität Bonn, Nussallee 12, 53115, Bonn, Germany
12
Université Libre de Bruxelles, Science Faculty CP230, 1050, Brussels, Belgium
13
Vrije Universiteit Brussel, Dienst ELEM, 1050, Brussels, Belgium
14
Department of Physics, Chiba University, Chiba, 263-8522, Japan
15
Department of Physics and Astronomy, University of Canterbury, Private Bag, 4800, Christchurch, New Zealand
16
Department of Physics, University of Maryland, College Park, MD, 20742, USA
17
Department of Physics, Center for Cosmology and Astro-Particle Physics, Ohio State University, Columbus, OH, 43210, USA
18
Department of Astronomy, Ohio State University, Columbus, OH, 43210, USA
19
Niels Bohr Institute, University of Copenhagen, 2100, Copenhagen, Denmark
20
Department of Physics, TU Dortmund University, 44221, Dortmund, Germany
21
Department of Physics, University of Alberta, Edmonton, AB, T6G 2E1, Canada
22
Erlangen Centre for Astroparticle Physics, Friedrich-Alexander-Universität Erlangen-Nürnberg, 91058, Erlangen, Germany
23
Département de physique nucléaire et corpusculaire, Université de Genève, 1211, Geneva, Switzerland
24
Department of Physics and Astronomy, University of Gent, 9000, Ghent, Belgium
25
Department of Physics and Astronomy, University of California, Irvine, CA, 92697, USA
26
Department of Physics and Astronomy, University of Kansas, Lawrence, KS, 66045, USA
27
Department of Astronomy, University of Wisconsin, Madison, WI, 53706, USA
28
Department of Physics, Wisconsin IceCube Particle Astrophysics Center, University of Wisconsin, Madison, WI, 53706, USA
29
Institute of Physics, University of Mainz, Staudinger Weg 7, 55099, Mainz, Germany
30
Université de Mons, 7000, Mons, Belgium
31
Technische Universität München, 85748, Garching, Germany
32
Department of Physics and Astronomy, Bartol Research Institute, University of Delaware, Newark, DE, 19716, USA
33
Department of Physics, University of Oxford, 1 Keble Road, Oxford, OX1 3NP, UK
34
Physics Department, South Dakota School of Mines and Technology, Rapid City, SD, 57701, USA
35
Department of Physics, University of Wisconsin, River Falls, WI, 54022, USA
36
Department of Physics, Oskar Klein Centre, Stockholm University, 10691, Stockholm, Sweden
37
Department of Physics and Astronomy, Stony Brook University, Stony Brook, NY, 11794-3800, USA
38
Department of Physics, Sungkyunkwan University, Suwon, 440-746, Korea
39
Department of Physics, University of Toronto, Toronto, ON, M5S 1A7, Canada
40
Department of Physics and Astronomy, University of Alabama, Tuscaloosa, AL, 35487, USA
41
Department of Astronomy and Astrophysics, Pennsylvania State University, University Park, PA, 16802, USA
42
Department of Physics, Pennsylvania State University, University Park, PA, 16802, USA
43
Department of Physics and Astronomy, Uppsala University, Box 516, 75120, Uppsala, Sweden
44
Department of Physics, University of Wuppertal, 42119, Wuppertal, Germany
45
DESY, 15735, Zeuthen, Germany
* e-mail: reimann@physik.rwth-aachen.de
Received:
27
June
2014
Accepted:
11
December
2014
Published online:
20
January
2015
Dark matter which is bound in the Galactic halo might self-annihilate and produce a flux of stable final state particles, e.g. high energy neutrinos. These neutrinos can be detected with IceCube, a cubic-kilometer sized Cherenkov detector. Given IceCube’s large field of view, a characteristic anisotropy of the additional neutrino flux is expected. In this paper we describe a multipole method to search for such a large-scale anisotropy in IceCube data. This method uses the expansion coefficients of a multipole expansion of neutrino arrival directions and incorporates signal-specific weights for each expansion coefficient. We apply the technique to a high-purity muon neutrino sample from the Northern Hemisphere. The final result is compatible with the null-hypothesis. As no signal was observed, we present limits on the self-annihilation cross-section averaged over the relative velocity distribution down to
for a dark matter particle mass of 700–1,000 GeV and direct annihilation into
. The resulting exclusion limits come close to exclusion limits from
-ray experiments, that focus on the outer Galactic halo, for high dark matter masses of a few TeV and hard annihilation channels.
© SIF and Springer-Verlag Berlin Heidelberg, 2015