Observation of Cosmic Ray Anisotropy with the IceTop Air Shower Array
High Energy Astrophysical Phenomena
2013-02-19 v4
Abstract
We report on the observation of anisotropy in the arrival direction distribution of cosmic rays at PeV energies. The analysis is based on data taken between 2009 and 2012 with the IceTop air shower array at the South Pole. IceTop, an integral part of the IceCube detector, is sensitive to cosmic rays between 100 TeV and 1 EeV. With the current size of the IceTop data set, searches for anisotropy at the 10^-3 level can, for the first time, be extended to PeV energies. We divide the data set into two parts with median energies of 400 TeV and 2 PeV, respectively. In the low energy band, we observe a strong deficit with an angular size of about 30 degrees and an amplitude of (-1.58 +/- 0.46 (stat) +/- 0.52 (sys)) x 10^(-3) at a location consistent with previous observations of cosmic rays with the IceCube neutrino detector. The study of the high energy band shows that the anisotropy persists to PeV energies and increases in amplitude to (-3.11 +/- 0.38 (stat) +/- 0.96 (sys)) x 10^(-3).
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Cite
@article{arxiv.1210.5278,
title = {Observation of Cosmic Ray Anisotropy with the IceTop Air Shower Array},
author = {IceCube Collaboration and M. G. Aartsen and R. Abbasi and Y. Abdou and M. Ackermann and J. Adams and J. A. Aguilar and M. Ahlers and D. Altmann and K. Andeen and J. Auffenberg and X. Bai and M. Baker and S. W. Barwick and V. Baum and R. Bay and K. Beattie and J. J. Beatty and S. Bechet and J. Becker Tjus and K. -H. Becker and M. Bell and M. L. Benabderrahmane and S. BenZvi and J. Berdermann and P. Berghaus and D. Berley and E. Bernardini and D. Bertrand and D. Z. Besson and D. Bindig and M. Bissok and E. Blaufuss and J. Blumenthal and D. J. Boersma and S. Bohaichuk and C. Bohm and D. Bose and S. Böser and O. Botner and L. Brayeur and A. M. Brown and R. Bruijn and J. Brunner and M. Carson and J. Casey and M. Casier and D. Chirkin and B. Christy and K. Clark and F. Clevermann and S. Cohen and D. F. Cowen and A. H. Cru. Silva and M. Danninger and J. Daughhetee and J. C. Davis and C. D. Clercq and S. D. Ridder and F. Descamps and P. Desiati and G. d. Vries-Uiterweerd and T. DeYoung and J. C. Díaz-Vélez and J. Dreyer and J. P. Dumm and M. Dunkman and R. Eagan and J. Eisch and R. W. Ellsworth and O. Engdegård and S. Euler and P. A. Evenson and O. Fadiran and A. R. Fazely and A. Fedynitch and J. Feintzeig and T. Feusels and K. Filimonov and C. Finley and T. Fischer-Wasels and S. Flis and A. Franckowiak and R. Franke and K. Frantzen and T. Fuchs and T. K. Gaisser and J. Gallagher and L. Gerhardt and L. Gladstone and T. Glüsenkamp and A. Goldschmidt and G. Golup and J. A. Goodman and D. Góra and D. Grant and A. Groß and S. Grullon and M. Gurtner and C. Ha and A. Ha. Ismail and A. Hallgren and F. Halzen and K. Hanson and D. Heereman and P. Heimann and D. Heinen and K. Helbing and R. Hellauer and S. Hickford and G. C. Hill and K. D. Hoffman and R. Hoffmann and A. Homeier and K. Hoshina and W. Huelsnitz and P. O. Hulth and K. Hultqvist and S. Hussain and A. Ishihara and E. Jacobi and J. Jacobsen and G. S. Japaridze and O. Jlelati and A. Kappes and T. Karg and A. Karle and J. Kiryluk and F. Kislat and J. Kläs and S. R. Klein and J. -H. Köhne and G. Kohnen and H. Kolanoski and L. Köpke and C. Kopper and S. Kopper and D. J. Koskinen and M. Kowalski and M. Krasberg and G. Kroll and J. Kunnen and N. Kurahashi and T. Kuwabara and M. Labare and H. Landsman and M. J. Larson and R. Lauer and M. Lesiak-Bzdak and J. Lünemann and J. Madsen and R. Maruyama and K. Mase and H. S. Matis and F. McNally and K. Meagher and M. Merck and P. Mészáros and T. Meures and S. Miarecki and E. Middell and N. Milke and J. Miller and L. Mohrmann and T. Montaruli and R. Morse and R. Nahnhauer and U. Naumann and S. C. Nowicki and D. R. Nygren and A. Obertacke and S. Odrowski and A. Olivas and M. Olivo and A. O'Murchadha and S. Panknin and L. Paul and J. A. Pepper and C. Pérez de los Heros and D. Pieloth and N. Pirk and J. Posselt and P. B. Price and G. T. Przybylski and L. Rädel and K. Rawlins and P. Redl and E. Resconi and W. Rhode and M. Ribordy and M. Richman and B. Riedel and J. P. Rodrigues and F. Rothmaier and C. Rott and T. Ruhe and B. Ruzybayev and D. Ryckbosch and S. M. Saba and T. Salameh and H. -G. Sander and M. Santander and S. Sarkar and K. Schatto and M. Scheel and F. Scheriau and T. Schmidt and M. Schmitz and S. Schoenen and S. Schöneberg and L. Schönherr and A. Schönwald and A. Schukraft and L. Schulte and O. Schulz and D. Seckel and S. H. Seo and Y. Sestayo and S. Seunarine and C. Sheremata and M. W. E. Smith and M. Soiron and D. Soldin and G. M. Spiczak and C. Spiering and M. Stamatikos and T. Stanev and A. Stasik and T. Stezelberger and R. G. Stokstad and A. Stößl and E. A. Strahler and R. Ström and G. W. Sullivan and H. Taavola and I. Taboada and A. Tamburro and S. Ter-Antonyan and S. Tilav and P. A. Toale and S. Toscano and M. Usner and D. va. de. Drift and N. va. Eijndhoven and A. Va. Overloop and J. va. Santen and M. Vehring and M. Voge and M. Vraeghe and C. Walck and T. Waldenmaier and M. Wallraff and M. Walter and R. Wasserman and Ch. Weaver and C. Wendt and S. Westerhoff and N. Whitehorn and K. Wiebe and C. H. Wiebusch and D. R. Williams and H. Wissing and M. Wolf and T. R. Wood and K. Woschnagg and C. Xu and D. L. Xu and X. W. Xu and J. P. Yanez and G. Yodh and S. Yoshida and P. Zarzhitsky and J. Ziemann and S. Zierke and A. Zilles and M. Zoll},
journal= {arXiv preprint arXiv:1210.5278},
year = {2013}
}
Comments
Accepted for publication in ApJ. Supplemental information available in the source file of the paper