학술논문

Flavor Ratio of Astrophysical Neutrinos above 35 TeV in IceCube
Document Type
Working Paper
Author
IceCube CollaborationAartsen, M. G.Ackermann, M.Adams, J.Aguilar, J. A.Ahlers, M.Ahrens, M.Altmann, D.Anderson, T.Arguelles, C.Arlen, T. C.Auffenberg, J.Bai, X.Barwick, S. W.Baum, V.Bay, R.Beatty, J. J.Tjus, J. BeckerBecker, K. -H.BenZvi, S.Berghaus, P.Berley, D.Bernardini, E.Bernhard, A.Besson, D. Z.Binder, G.Bindig, D.Bissok, M.Blaufuss, E.Blumenthal, J.Boersma, D. J.Bohm, C.Bos, F.Bose, D.Böser, S.Botner, O.Brayeur, L.Bretz, H. -P.Brown, A. M.Buzinsky, N.Casey, J.Casier, M.Cheung, E.Chirkin, D.Christov, A.Christy, B.Clark, K.Classen, L.Clevermann, F.Coenders, S.Cowen, D. F.Silva, A. H. CruzDaughhetee, J.Davis, J. C.Day, M.de André, J. P. A. M.De Clercq, C.Dembinski, H.De Ridder, S.Desiati, P.de Vries, K. D.de With, M.DeYoung, T.Díaz-Vélez, J. C.Dumm, J. P.Dunkman, M.Eagan, R.Eberhardt, B.Ehrhardt, T.Eichmann, B.Eisch, J.Euler, S.Evenson, P. A.Fadiran, O.Fazely, A. R.Fedynitch, A.Feintzeig, J.Felde, J.Filimonov, K.Finley, C.Fischer-Wasels, T.Flis, S.Frantzen, K.Fuchs, T.Gaisser, T. K.Gaior, R.Gallagher, J.Gerhardt, L.Gier, D.Gladstone, L.Glüsenkamp, T.Goldschmidt, A.Golup, G.Gonzalez, J. G.Goodman, J. A.Góra, D.Grant, D.Gretskov, P.Groh, J. C.Groß, A.Ha, C.Haack, C.Ismail, A. HajHallen, P.Hallgren, A.Halzen, F.Hanson, K.Hebecker, D.Heereman, D.Heinen, D.Helbing, K.Hellauer, R.Hellwig, D.Hickford, S.Hill, G. C.Hoffman, K. D.Hoffmann, R.Homeier, A.Hoshina, K.Huang, F.Huelsnitz, W.Hulth, P. O.Hultqvist, K.Ishihara, A.Jacobi, E.Jacobsen, J.Japaridze, G. S.Jero, K.Jurkovic, M.Kaminsky, B.Kappes, A.Karg, T.Karle, A.Kauer, M.Keivani, A.Kelley, J. L.Kheirandish, A.Kiryluk, J.Kläs, J.Klein, S. R.Köhne, J. -H.Kohnen, G.Kolanoski, H.Koob, A.Köpke, L.Kopper, C.Kopper, S.Koskinen, D. J.Kowalski, M.Kriesten, A.Krings, K.Kroll, G.Kroll, M.Kunnen, J.Kurahashi, N.Kuwabara, T.Labare, M.Lanfranchi, J. L.Larsen, D. T.Larson, M. J.Lesiak-Bzdak, M.Leuermann, M.Lünemann, J.Madsen, J.Maggi, G.Maruyama, R.Mase, K.Matis, H. S.Maunu, R.McNally, F.Meagher, K.Medici, M.Meli, A.Meures, T.Miarecki, S.Middell, E.Middlemas, E.Milke, N.Miller, J.Mohrmann, L.Montaruli, T.Morse, R.Nahnhauer, R.Naumann, U.Niederhausen, H.Nowicki, S. C.Nygren, D. R.Obertacke, A.Olivas, A.Omairat, A.O'Murchadha, A.Palczewski, T.Paul, L.Penek, Ö.Pepper, J. A.Heros, C. Pérez de losPfendner, C.Pieloth, D.Pinat, E.Posselt, J.Price, P. B.Przybylski, G. T.Pütz, J.Quinnan, M.Rädel, L.Rameez, M.Rawlins, K.Redl, P.Rees, I.Reimann, R.Relich, M.Resconi, E.Rhode, W.Richman, M.Riedel, B.Robertson, S.Rodrigues, J. P.Rongen, M.Rott, C.Ruhe, T.Ruzybayev, B.Ryckbosch, D.Saba, S. M.Sander, H. -G.Sandroos, J.Santander, M.Sarkar, S.Schatto, K.Scheriau, F.Schmidt, T.Schmitz, M.Schoenen, S.Schöneberg, S.Schönwald, A.Schukraft, A.Schulte, L.Schulz, O.Seckel, D.Sestayo, Y.Seunarine, S.Shanidze, R.Smith, M. W. E.Soldin, D.Spiczak, G. M.Spiering, C.Stamatikos, M.Stanev, T.Stanisha, N. A.Stasik, A.Stezelberger, T.Stokstad, R. G.Stößl, A.Strahler, E. A.Ström, R.Strotjohann, N. L.Sullivan, G. W.Sutherland, M.Taavola, H.Taboada, I.Tamburro, A.Ter-Antonyan, S.Terliuk, A.Tešić, G.Tilav, S.Toale, P. A.Tobin, M. N.Tosi, D.Tselengidou, M.Unger, E.Usner, M.Vallecorsa, S.van Eijndhoven, N.Vandenbroucke, J.van Santen, J.Vanheule, S.Vehring, M.Voge, M.Vraeghe, M.Walck, C.Wallraff, M.Weaver, Ch.Wellons, M.Wendt, C.Westerhoff, S.Whelan, B. J.Whitehorn, N.Wichary, C.Wiebe, K.Wiebusch, C. H.Williams, D. R.Wissing, H.Wolf, M.Wood, T. R.Woschnagg, K.Xu, D. L.Xu, X. W.Xu, Y.Yanez, J. P.Yodh, G.Yoshida, S.Zarzhitsky, P.Ziemann, J.Zoll, M.
Source
Phys. Rev. Lett. 114, 171102 (2015)
Subject
Astrophysics - High Energy Astrophysical Phenomena
High Energy Physics - Experiment
Language
Abstract
A diffuse flux of astrophysical neutrinos above $100\,\mathrm{TeV}$ has been observed at the IceCube Neutrino Observatory. Here we extend this analysis to probe the astrophysical flux down to $35\,\mathrm{TeV}$ and analyze its flavor composition by classifying events as showers or tracks. Taking advantage of lower atmospheric backgrounds for shower-like events, we obtain a shower-biased sample containing 129 showers and 8 tracks collected in three years from 2010 to 2013. We demonstrate consistency with the $(f_e:f_{\mu}:f_\tau)_\oplus\approx(1:1:1)_\oplus$ flavor ratio at Earth commonly expected from the averaged oscillations of neutrinos produced by pion decay in distant astrophysical sources. Limits are placed on non-standard flavor compositions that cannot be produced by averaged neutrino oscillations but could arise in exotic physics scenarios. A maximally track-like composition of $(0:1:0)_\oplus$ is excluded at $3.3\sigma$, and a purely shower-like composition of $(1:0:0)_\oplus$ is excluded at $2.3\sigma$.
Comment: 8 pages, 3 figures. Submitted to PRL