Observation of an Anisotropy in the Galactic Cosmic Ray arrival direction at 400 TeV with IceCube
High Energy Physics - Experiment
2012-01-25 v1 High Energy Astrophysical Phenomena
Abstract
In this paper we report the first observation in the Southern hemisphere of an energy dependence in the Galactic cosmic ray anisotropy up to a few hundred TeV. This measurement was performed using cosmic ray induced muons recorded by the partially deployed IceCube observatory between May 2009 and May 2010. The data include a total of 33 muon events with a median angular resolution of degrees. A sky map of the relative intensity in arrival direction over the Southern celestial sky is presented for cosmic ray median energies of 20 and 400 TeV. The same large-scale anisotropy observed at median energies around 20 TeV is not present at 400 TeV. Instead, the high energy skymap shows a different anisotropy structure including a deficit with a post-trial significance of -6.3. This anisotropy reveals a new feature of the Galactic cosmic ray distribution, which must be incorporated into theories of the origin and propagation of cosmic rays.
Keywords
Cite
@article{arxiv.1109.1017,
title = {Observation of an Anisotropy in the Galactic Cosmic Ray arrival direction at 400 TeV with IceCube},
author = {IceCube Collaboration and R. Abbasi and Y. Abdou and T. Abu-Zayyad and M. Ackermann and J. Adams and J. A. Aguilar and M. Ahlers and M. M. Allen and D. Altmann and K. Andeen and J. Auffenberg and X. Bai and M. Baker and S. W. Barwick and R. Bay and J. L. Bazo Alba and K. Beattie and J. J. Beatty and S. Bechet and J. K. Becker and K. -H. Becker 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 C. Bohm and D. Bose and S. Böser and O. Botner and A. M. Brown and S. Buitink and K. S. Caballero-Mora and M. Carson and D. Chirkin and B. Christy and F. Clevermann and S. Cohen and C. Colnard and D. F. Cowen and A. H. Cruz Silva and M. V. D'Agostino and M. Danninger and J. Daughhetee and J. C. Davis and C. De Clercq and T. Degner and L. Demirörs and F. Descamps and P. Desiati and G. de Vries-Uiterweerd and T. DeYoung and J. C. Díaz-Vélez and M. Dierckxsens and J. Dreyer and J. P. Dumm and M. Dunkman 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 B. D. Fox and A. Franckowiak and R. Franke and T. K. Gaisser and J. Gallagher and L. Gerhardt and L. Gladstone and T. Glüsenkamp and A. Goldschmidt and J. A. Goodman and D. Góra and D. Grant and T. Griesel and A. Groß and S. Grullon and M. Gurtner and C. Ha and A. Haj Ismail and A. Hallgren and F. Halzen and K. Han and K. Hanson and D. Heinen and K. Helbing and R. Hellauer and S. Hickford and G. C. Hill and K. D. Hoffman and B. Hoffmann and A. Homeier and K. Hoshina and W. Huelsnitz and J. -P. Hülß and P. O. Hulth and K. Hultqvist and S. Hussain and A. Ishihara and E. Jacobi and J. Jacobsen and G. S. Japaridze and H. Johansson and K. -H. Kampert and A. Kappes and T. Karg and A. Karle and P. Kenny and J. Kiryluk and F. Kislat and S. R. Klein and J. -H. Köhne and G. Kohnen and H. Kolanoski and L. Köpke and S. Kopper and D. J. Koskinen and M. Kowalski and T. Kowarik and M. Krasberg and G. Kroll and N. Kurahashi and T. Kuwabara and M. Labare and K. Laihem and H. Landsman and M. J. Larson and R. Lauer and J. Lünemann and J. Madsen and A. Marotta and R. Maruyama and K. Mase and H. S. Matis 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 T. Montaruli and R. Morse and S. M. Movit and R. Nahnhauer and J. W. Nam and U. Naumann and D. R. Nygren and S. Odrowski and A. Olivas and M. Olivo and A. O'Murchadha and S. Panknin and L. Paul and C. Pérez de los Heros and J. Petrovic and A. Piegsa and D. Pieloth and R. Porrata and J. Posselt and C. C. Price and P. B. Price and G. T. Przybylski and K. Rawlins and P. Redl and E. Resconi and W. Rhode and M. Ribordy and M. Richman and J. P. Rodrigues and F. Rothmaier and C. Rott and T. Ruhe and D. Rutledge and B. Ruzybayev and D. Ryckbosch and H. -G. Sander and M. Santander and S. Sarkar and K. Schatto and T. Schmidt and A. Schönwald and A. Schukraft and A. Schultes and O. Schulz and M. Schunck and D. Seckel and B. Semburg and S. H. Seo and Y. Sestayo and S. Seunarine and A. Silvestri and G. M. Spiczak and C. Spiering and M. Stamatikos and T. Stanev and T. Stezelberger and R. G. Stokstad and A. Stößl and E. A. Strahler and R. Ström and M. Stüer and G. W. Sullivan and Q. Swillens and H. Taavola and I. Taboada and A. Tamburro and A. Tepe and S. Ter-Antonyan and S. Tilav and P. A. Toale and S. Toscano and D. Tosi and N. van Eijndhoven and J. Vandenbroucke and A. Van Overloop and J. van Santen and M. Vehring and M. Voge and C. Walck and T. Waldenmaier and M. Wallraff and M. Walter and Ch. Weaver and C. Wendt and S. Westerhoff and N. Whitehorn and K. Wiebe and C. H. Wiebusch and D. R. Williams and R. Wischnewski 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 M. Zoll},
journal= {arXiv preprint arXiv:1109.1017},
year = {2012}
}