SEARCH for SOURCES of HIGH-ENERGY NEUTRONS with FOUR YEARS of DATA from the ICETOP DETECTOR

• Published in: The Astrophysical Journal
• Main Authors: Aartsen, MG, Abraham, K, Ackermann, M, Adams, J, Aguilar, JA, Ahlers, M, Ahrens, M, Altmann, D, Andeen, K, Anderson, T, Ansseau, I, Anton, G, Archinger, M, Argüelles, C, Auffenberg, J, Axani, S, Bai, X, Barwick, SW, Baum, V, Bay, R, Beatty, JJ, Tjus, JB, Becker, KH, Benzvi, S, Berghaus, P, Berley, D, Bernardini, E, Bernhard, A, Besson, DZ, Binder, G, Bindig, D, Bissok, M, Blaufuss, E, Blot, S, Bohm, C, Börner, M, Bos, F, Bose, D, Böser, S, Botner, O, Braun, J, Brayeur, L, Bretz, HP, Burgman, A, Carver, T, Casier, M, Cheung, E, Chirkin, D, Christov, A, Clark, K, Classen, L, Coenders, S, Collin, GH, Conrad, JM, Cowen, DF, Cross, R, Day, M, André, JPAMD, Clercq, CD, Rosendo, EDP, Dembinski, H, Ridder, SD, Desiati, P, Vries, KDD, Wasseige, GD, With, MD, Deyoung, T, Díaz-Vélez, JC, Lorenzo, VD, Dujmovic, H, Dumm, JP, Dunkman, M, Eberhardt, B, Ehrhardt, T, Eichmann, B, Eller, P, Euler, S, Evenson, PA, Fahey, S, Fazely, AR, Feintzeig, J, Felde, J, Filimonov, K, Finley, C, Flis, S, Fösig, CC, Franckowiak, A, Friedman, E, Fuchs, T, Gaisser, TK, Gallagher, J, Gerhardt, L, Ghorbani, K, Giang, W, Gladstone, L, Glagla, M
• Format: Article in Journal/Newspaper
• Language: English
• Published: eScholarship, University of California 2016
• Subjects: Antarctic; South Pole; The Antarctic; Antarc*; Ice Sheet; South pole
• Online Access: http://www.escholarship.org/uc/item/8st4x6b6

© 2016. The American Astronomical Society. All rights reserved. IceTop is an air-shower array located on the Antarctic ice sheet at the geographic South Pole. IceTop can detect an astrophysical flux of neutrons from Galactic sources as an excess of cosmic-ray air showers arriving from the source direction. Neutrons are undeflected by the Galactic magnetic field and can typically travel 10 (E/PeV) pc before decay. Two searches are performed using 4 yr of the IceTop data set to look for a statistically significant excess of events with energies above 10 PeV (1016eV) arriving within a small solid angle. The all-sky search method covers from -90° to approximately -50° in declination. No significant excess is found. A targeted search is also performed, looking for significant correlation with candidate sources in different target sets. This search uses a higher-energy cut (100 PeV) since most target objects lie beyond 1 kpc. The target sets include pulsars with confirmed TeV energy photon fluxes and high-mass X-ray binaries. No significant correlation is found for any target set. Flux upper limits are determined for both searches, which can constrain Galactic neutron sources and production scenarios.