https://doi.org/10.1140/epjc/s10052-015-3330-z
Regular Article - Experimental Physics
Development of a general analysis and unfolding scheme and its application to measure the energy spectrum of atmospheric neutrinos with IceCube
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 & 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 and 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 Computer Science, TU Dortmund University, 44221, Dortmund, Germany
22
Department of Physics, University of Alberta, Edmonton, AB, T6G 2E1, Canada
23
Erlangen Centre for Astroparticle Physics, Friedrich-Alexander-Universität Erlangen-Nürnberg, 91058, Erlangen, Germany
24
Département de physique nucléaire et corpusculaire, Université de Genève, 1211, Geneva, Switzerland
25
Department of Physics and Astronomy, University of Gent, 9000, Ghent, Belgium
26
Department of Physics and Astronomy, University of California, Irvine, CA, 92697, USA
27
Department of Physics and Astronomy, University of Kansas, Lawrence, KS, 66045, USA
28
Department of Astronomy, University of Wisconsin, Madison, WI, 53706, USA
29
Department of Physics and Wisconsin IceCube Particle Astrophysics Center, University of Wisconsin, Madison, WI, 53706, USA
30
Institute of Physics, University of Mainz, Staudinger Weg 7, 55099, Mainz, Germany
31
Université de Mons, 7000, Mons, Belgium
32
Technische Universität München, 85748, Garching, Germany
33
Department of Physics and Astronomy, Bartol Research Institute, University of Delaware, Newark, DE, 19716, USA
34
Department of Physics, University of Oxford, 1 Keble Road, Oxford, OX1 3NP, UK
35
Physics Department, South Dakota School of Mines and Technology, Rapid City, SD, 57701, USA
36
Department of Physics, University of Wisconsin, River Falls, WI, 54022, USA
37
Department of Physics, Oskar Klein Centre, Stockholm University, 10691, Stockholm, Sweden
38
Department of Physics and Astronomy, Stony Brook University, Stony Brook, NY, 11794-3800, USA
39
Department of Physics, Sungkyunkwan University, Suwon, 440-746, Korea
40
Department of Physics, University of Toronto, Toronto, ON, M5S 1A7, Canada
41
Department of Physics and Astronomy, University of Alabama, Tuscaloosa, AL, 35487, USA
42
Department of Astronomy and Astrophysics, Pennsylvania State University, University Park, PA, 16802, USA
43
Department of Physics, Pennsylvania State University, University Park, PA, 16802, USA
44
Department of Physics and Astronomy, Uppsala University, Box 516, 75120, Uppsala, Sweden
45
Department of Physics, University of Wuppertal, 42119, Wuppertal, Germany
46
DESY, 15735, Zeuthen, Germany
* e-mail: tim.ruhe@udo.edu
Received:
15
September
2014
Accepted:
19
February
2015
Published online:
11
March
2015
We present the development and application of a generic analysis scheme for the measurement of neutrino spectra with the IceCube detector. This scheme is based on regularized unfolding, preceded by an event selection which uses a Minimum Redundancy Maximum Relevance algorithm to select the relevant variables and a random forest for the classification of events. The analysis has been developed using IceCube data from the 59-string configuration of the detector. 27,771 neutrino candidates were detected in 346 days of livetime. A rejection of 99.9999 % of the atmospheric muon background is achieved. The energy spectrum of the atmospheric neutrino flux is obtained using the TRUEE unfolding program. The unfolded spectrum of atmospheric muon neutrinos covers an energy range from 100 GeV to 1 PeV. Compared to the previous measurement using the detector in the 40-string configuration, the analysis presented here, extends the upper end of the atmospheric neutrino spectrum by more than a factor of two, reaching an energy region that has not been previously accessed by spectral measurements.
© SIF and Springer-Verlag Berlin Heidelberg, 2015