Eur. Phys. J. C (2020) 80: 9
https://doi.org/10.1140/epjc/s10052-019-7555-0

Regular Article - Experimental Physics

Development of an analysis to probe the neutrino mass ordering with atmospheric neutrinos using three years of IceCube DeepCore data

IceCube Collaboration

¹ III. Physikalisches Institut, RWTH Aachen University, 52056, Aachen, Germany
² Department of Physics, University of Adelaide, Adelaide, 5005, Australia
³ Department of Physics and Astronomy, University of Alaska Anchorage, 3211 Providence Dr., Anchorage, AK, 99508, USA
⁴ Department of Physics, University of Texas at Arlington, 502 Yates St., Science Hall Rm 108, Box 19059, Arlington, TX, 76019, USA
⁵ CTSPS, Clark-Atlanta University, Atlanta, GA, 30314, USA
⁶ School of Physics and Center for Relativistic Astrophysics, Georgia Institute of Technology, Atlanta, GA, 30332, USA
⁷ Department of Physics, Southern University, Baton Rouge, LA, 70813, USA
⁸ Department of Physics, University of California, Berkeley, CA, 94720, USA
⁹ Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, USA
¹⁰ Institut für Physik, Humboldt-Universität zu Berlin, 12489, Berlin, Germany
¹¹ Fakultät für Physik & Astronomie, Ruhr-Universität Bochum, 44780, Bochum, Germany
¹² Université Libre de Bruxelles, Science Faculty CP230, 1050, Brussels, Belgium
¹³ Vrije Universiteit Brussel (VUB), Dienst ELEM, 1050, Brussels, Belgium
¹⁴ Department of Physics, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA
¹⁵ Department of Physics and Institute for Global Prominent Research, Chiba University, Chiba, 263-8522, Japan
¹⁶ Department  of Physics and Astronomy, University of Canterbury, Private Bag 4800, Christchurch, New Zealand
¹⁷ Department  of Physics, University of Maryland, College Park, MD, 20742, USA
¹⁸ Department  of Physics and Center for Cosmology and Astro-Particle Physics, Ohio State University, Columbus, OH, 43210, USA
¹⁹ Department  of Astronomy, Ohio State University, Columbus, OH, 43210, USA
²⁰ Niels Bohr Institute, University of Copenhagen, 2100, Copenhagen, Denmark
²¹ Department  of Physics, TU Dortmund University, 44221, Dortmund, Germany
²² Department  of Physics and Astronomy, Michigan State University, East Lansing, MI, 48824, USA
²³ Department  of Physics, University of Alberta, Edmonton, AB, T6G 2E1, Canada
²⁴ Erlangen Centre for Astroparticle Physics, Friedrich-Alexander-Universität Erlangen-Nürnberg, 91058, Erlangen, Germany
²⁵ Département de physique nucléaire et corpusculaire, Université de Genève, 1211, Geneva, Switzerland
²⁶ Department  of Physics and Astronomy, University of Gent, 9000, Gent, Belgium
²⁷ Department  of Physics and Astronomy, University of California, Irvine, CA, 92697, USA
²⁸ Department  of Physics and Astronomy, University of Kansas, Lawrence, KS, 66045, USA
²⁹ SNOLAB, 1039 Regional Road 24, Creighton Mine 9, Lively, ON, P3Y 1N2, Canada
³⁰ Department of Physics and Astronomy, UCLA, Los Angeles, CA, 90095, USA
³¹ Department  of Astronomy, University of Wisconsin, Madison, WI, 53706, USA
³² Department  of Physics and Wisconsin IceCube Particle Astrophysics Center, University of Wisconsin, Madison, WI, 53706, USA
³³ Institute of Physics, University of Mainz, Staudinger Weg 7, 55099, Mainz, Germany
³⁴ School of Physics and Astronomy, The University of Manchester, Oxford Road, Manchester, M13 9PL, UK
³⁵ Department of Physics, Marquette University, Milwaukee, WI, 53201, USA
³⁶ Physik-department, Technische Universität München, 85748, Garching, Germany
³⁷ Institut für Kernphysik, Westfälische Wilhelms-Universität Münster, 48149, Münster, Germany
³⁸ Bartol Research Institute and Department  of Physics and Astronomy, University of Delaware, Newark, DE, 19716, USA
³⁹ Department  of Physics, Yale University, New Haven, CT, 06520, USA
⁴⁰ Department  of Physics, University of Oxford, 1 Keble Road, Oxford, OX1 3NP, UK
⁴¹ Department  of Physics, Drexel University, 3141 Chestnut Street, Philadelphia, PA, 19104, USA
⁴² Physics Department, South Dakota School of Mines and Technology, Rapid City, SD, 57701, USA
⁴³ Department  of Physics, University of Wisconsin, River Falls, WI, 54022, USA
⁴⁴ Department  of Physics and Astronomy, University of Rochester, Rochester, NY, 14627, USA
⁴⁵ Oskar Klein Centre and Department  of Physics, Stockholm University, 10691, Stockholm, Sweden
⁴⁶ Department  of Physics and Astronomy, Stony Brook University, Stony Brook, NY, 11794-3800, USA
⁴⁷ Department  of Physics, Sungkyunkwan University, Suwon, 440-746, Korea
⁴⁸ Department  of Physics and Astronomy, University of Alabama, Tuscaloosa, AL, 35487, USA
⁴⁹ Department  of Astronomy and Astrophysics, Pennsylvania State University, University Park, PA, 16802, USA
⁵⁰ Department  of Physics, Pennsylvania State University, University Park, PA, 16802, USA
⁵¹ Department  of Physics and Astronomy, Uppsala University, Box 516, 75120, Uppsala, Sweden
⁵² Department  of Physics, University of Wuppertal, 42119, Wuppertal, Germany
⁵³ DESY, 15738, Zeuthen, Germany

^* e-mail: justin.evans@manchester.ac.uk

Received: 20 February 2019
Accepted: 11 December 2019
Published online: 4 January 2020

Abstract

The Neutrino Mass Ordering (NMO) remains one of the outstanding questions in the field of neutrino physics. One strategy to measure the NMO is to observe matter effects in the oscillation pattern of atmospheric neutrinos above , as proposed for several next-generation neutrino experiments. Moreover, the existing IceCube DeepCore detector can already explore this type of measurement. We present the development and application of two independent analyses to search for the signature of the NMO with three years of DeepCore data. These analyses include a full treatment of systematic uncertainties and a statistically-rigorous method to determine the significance for the NMO from a fit to the data. Both analyses show that the dataset is fully compatible with both mass orderings. For the more sensitive analysis, we observe a preference for normal ordering with a p-value of and for the inverted ordering hypothesis, while the experimental results from both analyses are consistent within their uncertainties. Since the result is independent of the value of and obtained from energies , it is complementary to recent results from long-baseline experiments. These analyses set the groundwork for the future of this measurement with more capable detectors, such as the IceCube Upgrade and the proposed PINGU detector.