Characteristics of the diffuse astrophysical electron and tau neutrino flux with six years of IceCube high energy cascade data
Creators: name: IceCube Collaboration
name: Aartsen, M. G.
name: Ackermann, M.
name: Adams, J.
name: Aguilar, J. A.
name: Ahlers, M.
name: Ahrens, M.
name: Alispach, C.
name: Andeen, K.
name: Anderson, T.
name: Ansseau, I.
name: Anton, G.
name: Argüelles, C.
name: Auffenberg, J.
name: Axani, S.
name: Backes, P.
name: Bagherpour, H.
name: Bai, X.
name: V., A. Balagopal
name: Barbano, A.
name: Barwick, S. W.
name: Bastian, B.
name: Baum, V.
name: Baur, S.
name: Bay, R.
name: Beatty, J. J.
name: Becker, K. -H.
name: Tjus, J. Becker
name: BenZvi, S.
name: Berley, D.
name: Bernardini, E.
name: Besson, D. Z.
name: Binder, G.
name: Bindig, D.
name: Blaufuss, E.
name: Blot, S.
name: Bohm, C.
name: Böser, S.
name: Botner, O.
name: Böttcher, J.
name: Bourbeau, E.
name: Bourbeau, J.
name: Bradascio, F.
name: Braun, J.
name: Bron, S.
name: Brostean-Kaiser, J.
name: Burgman, A.
name: Buscher, J.
name: Busse, R. S.
name: Carver, T.
name: Chen, C.
name: Cheung, E.
name: Chirkin, D.
name: Choi, S.
name: Clark, K.
name: Classen, L.
name: Coleman, A.
name: Collin, G. H.
name: Conrad, J. M.
name: Coppin, P.
name: Correa, P.
name: Cowen, D. F.
name: Cross, R.
name: Dave, P.
name: De Clercq, C.
name: DeLaunay, J. J.
name: Dembinski, H.
name: Deoskar, K.
name: De Ridder, S.
name: Desiati, P.
name: de Vries, K. D.
name: de Wasseige, G.
name: de With, M.
name: DeYoung, T.
name: Diaz, A.
name: Díaz-Vélez, J. C.
name: Dujmovic, H.
name: Dunkman, M.
name: Dvorak, E.
name: Eberhardt, B.
name: Ehrhardt, T.
name: Eller, P.
name: Engel, R.
name: Evenson, P. A.
name: Fahey, S.
name: Fazely, A. R.
name: Felde, J.
name: Filimonov, K.
name: Finley, C.
name: Fox, D.
name: Franckowiak, A.
name: Friedman, E.
name: Fritz, A.
name: Gaisser, T. K.
name: Gallagher, J.
name: Ganster, E.
name: Garrappa, S.
name: Gerhardt, L.
name: Ghorbani, K.
name: Glauch, T.
name: Glüsenkamp, T.
name: Goldschmidt, A.
name: Gonzalez, J. G.
name: Grant, D.
name: Grégoire, T.
name: Griffith, Z.
name: Griswold, S.
name: Günder, M.
name: Gündüz, M.
name: Haack, C.
name: Hallgren, A.
name: Halliday, R.
name: Halve, L.
name: Halzen, F.
name: Hanson, K.
name: Haungs, A.
name: Hebecker, D.
name: Heereman, D.
name: Heix, P.
name: Helbing, K.
name: Hellauer, R.
name: Henningsen, F.
name: Hickford, S.
name: Hignight, J.
name: Hill, G. C.
name: Hoffman, K. D.
name: Hoffmann, R.
name: Hoinka, T.
name: Hokanson-Fasig, B.
name: Hoshina, K.
name: Huang, F.
name: Huber, M.
name: Huber, T.
name: Hultqvist, K.
name: Hünnefeld, M.
name: Hussain, R.
name: In, S.
name: Iovine, N.
name: Ishihara, A.
name: Jansson, M.
name: Japaridze, G. S.
name: Jeong, M.
name: Jero, K.
name: Jones, B. J. P.
name: Jonske, F.
name: Joppe, R.
name: Kang, D.
name: Kang, W.
name: Kappes, A.
name: Kappesser, D.
name: Karg, T.
name: Karl, M.
name: Karle, A.
name: Katz, U.
name: Kauer, M.
name: Kelley, J. L.
name: Kheirandish, A.
name: Kim, J.
name: Kintscher, T.
name: Kiryluk, J.
name: Kittler, T.
name: Klein, S. R.
name: Koirala, R.
name: Kolanoski, H.
name: Köpke, L.
name: Kopper, C.
name: Kopper, S.
name: Koskinen, D. J.
name: Kowalski, M.
name: Krings, K.
name: Krückl, G.
name: Kulacz, N.
name: Kurahashi, N.
name: Kyriacou, A.
name: Lanfranchi, J. L.
name: Larson, M. J.
name: Lauber, F.
name: Lazar, J. P.
name: Leonard, K.
name: Lesiak-Bzdak, M.
name: Leszczyńska, A.
name: Leuermann, M.
name: Liu, Q. R.
name: Lohfink, E.
name: Mariscal, C. J. Lozano
name: Lu, L.
name: Lucarelli, F.
name: Lünemann, J.
name: Luszczak, W.
name: Lyu, Y.
name: Ma, W. Y.
name: Madsen, J.
name: Maggi, G.
name: Mahn, K. B. M.
name: Makino, Y.
name: Mallik, P.
name: Mallot, K.
name: Mancina, S.
name: Mari{ş}, I. C.
name: Maruyama, R.
name: Mase, K.
name: Maunu, R.
name: McNally, F.
name: Meagher, K.
name: Medici, M.
name: Medina, A.
name: Meier, M.
name: Meighen-Berger, S.
name: Merino, G.
name: Meures, T.
name: Micallef, J.
name: Mockler, D.
name: Momenté, G.
name: Montaruli, T.
name: Moore, R. W.
name: Morse, R.
name: Moulai, M.
name: Muth, P.
name: Nagai, R.
name: Naumann, U.
name: Neer, G.
name: Niederhausen, H.
name: Nisa, M. U.
name: Nowicki, S. C.
name: Nygren, D. R.
name: Pollmann, A. Obertacke
name: Oehler, M.
name: Olivas, A.
name: O'Murchadha, A.
name: O'Sullivan, E.
name: Palczewski, T.
name: Pandya, H.
name: Pankova, D. V.
name: Park, N.
name: Peiffer, P.
name: Heros, C. Pérez de los
name: Philippen, S.
name: Pieloth, D.
name: Pinat, E.
name: Pizzuto, A.
name: Plum, M.
name: Porcelli, A.
name: Price, P. B.
name: Przybylski, G. T.
name: Raab, C.
name: Raissi, A.
name: Rameez, M.
name: Rauch, L.
name: Rawlins, K.
name: Rea, I. C.
name: Rehman, A.
name: Reimann, R.
name: Relethford, B.
name: Renschler, M.
name: Renzi, G.
name: Resconi, E.
name: Rhode, W.
name: Richman, M.
name: Robertson, S.
name: Rongen, M.
name: Rott, C.
name: Ruhe, T.
name: Ryckbosch, D.
name: Rysewyk, D.
name: Safa, I.
name: Herrera, S. E. Sanchez
name: Sandrock, A.
name: Sandroos, J.
name: Santander, M.
name: Sarkar, S.
name: Sarkar, S.
name: Satalecka, K.
name: Schaufel, M.
name: Schieler, H.
name: Schlunder, P.
name: Schmidt, T.
name: Schneider, A.
name: Schneider, J.
name: Schröder, F. G.
name: Schumacher, L.
name: Sclafani, S.
name: Seckel, D.
name: Seunarine, S.
name: Shefali, S.
name: Silva, M.
name: Snihur, R.
name: Soedingrekso, J.
name: Soldin, D.
name: Song, M.
name: Spiczak, G. M.
name: Spiering, C.
name: Stachurska, J.
name: Stamatikos, M.
name: Stanev, T.
name: Stein, R.
name: Stettner, J.
name: Steuer, A.
name: Stezelberger, T.
name: Stokstad, R. G.
name: Stößl, A.
name: Strotjohann, N. L.
name: Stürwald, T.
name: Stuttard, T.
name: Sullivan, G. W.
name: Taboada, I.
name: Tenholt, F.
name: Ter-Antonyan, S.
name: Terliuk, A.
name: Tilav, S.
name: Tollefson, K.
name: Tomankova, L.
name: Tönnis, C.
name: Toscano, S.
name: Tosi, D.
name: Trettin, A.
name: Tselengidou, M.
name: Tung, C. F.
name: Turcati, A.
name: Turcotte, R.
name: Turley, C. F.
name: Ty, B.
name: Unger, E.
name: Elorrieta, M. A. Unland
name: Usner, M.
name: Vandenbroucke, J.
name: Van Driessche, W.
name: van Eijk, D.
name: van Eijndhoven, N.
name: van Santen, J.
name: Verpoest, S.
name: Vraeghe, M.
name: Walck, C.
name: Wallace, A.
name: Wallraff, M.
name: Wandkowsky, N.
name: Watson, T. B.
name: Weaver, C.
name: Weindl, A.
name: Weiss, M. J.
name: Weldert, J.
name: Wendt, C.
name: Werthebach, J.
name: Whelan, B. J.
name: Whitehorn, N.
name: Wiebe, K.
name: Wiebusch, C. H.
name: Wille, L.
name: Williams, D. R.
name: Wills, L.
name: Wolf, M.
name: Wood, J.
name: Wood, T. R.
name: Woschnagg, K.
name: Wrede, G.
name: Xu, D. L.
name: Xu, X. W.
name: Xu, Y.
name: Yanez, J. P.
name: Yodh, G.
name: Yoshida, S.
name: Yuan, T.
name: Zöcklein, M.
Publisher: name: arXiv
Year: 2020
Subjects: subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: FOS: Physical sciences
subject: FOS: Physical sciences

description: We report on the first measurement of the astrophysical neutrino flux using particle showers (cascades) in IceCube data from 2010 -- 2015. Assuming standard oscillations, the astrophysical neutrinos in this dedicated cascade sample are dominated ($\sim 90 \%$) by electron and tau flavors. The flux, observed in the sensitive energy range from $16\,\mathrm{TeV}$ to $2.6\,\mathrm{PeV}$, is consistent with a single power-law model as expected from Fermi-type acceleration of high energy particles at astrophysical sources. We find the flux spectral index to be $γ=2.53\pm0.07$ and a flux normalization for each neutrino flavor of $ϕ_{astro} = 1.66^{+0.25}_{-0.27}$ at $E_{0} = 100\, \mathrm{TeV}$, in agreement with IceCube's complementary muon neutrino results and with all-neutrino flavor fit results. In the measured energy range we reject spectral indices $γ\leq2.28$ at $\ge3σ$ significance level. Due to high neutrino energy resolution and low atmospheric neutrino backgrounds, this analysis provides the most detailed characterization of the neutrino flux at energies below $\sim100\,{\rm{TeV}}$ compared to previous IceCube results. Results from fits assuming more complex neutrino flux models suggest a flux softening at high energies and a flux hardening at low energies (p-value $\ge 0.06$). The sizable and smooth flux measured below $\sim 100\,{\rm{TeV}}$ remains a puzzle. In order to not violate the isotropic diffuse gamma-ray background as measured by the Fermi-LAT, it suggests the existence of astrophysical neutrino sources characterized by dense environments which are opaque to gamma-rays.
description: 4 figures, 4 tables, includes supplementary material