Prof Subir Sarkar: Publications

IceCube

IceCube at 91̽��

I am a member since 2004 of the IceCube collaboration which discovered cosmic high energy neutrinos and identified some of their astrophysical sources.

IceCube @ 91̽��

The search for Muon neutrinos from northern hemisphere gamma-ray bursts with AMANDA

Astrophysical Journal 674:1 (2008) 357-370

Authors:

A Achterberg, M Ackermann, J Adams, J Ahrens, K Andeen, J Auffenberg, JN Bahcall, X Bai, B Baret, SW Barwick, R Bay, K Beattie, T Becka, JK Becker, KH Becker, P Berghaus, D Berley, E Bernardini, D Bertrand, DZ Besson, E Blaufuss, DJ Boersma, C Bohm, J Bolmont, S Böser, O Botner, A Bouchta, J Braun, C Burgess, T Burgess, T Castermans, D Chirkin, B Christy, J Clem, DF Cowen, MV D'Agostino, A Davour, CT Day, C De Clercq, L Demirörs, F Descamps, P Desiati, T DeYoung, JC Diaz-Velez, J Dreyer, JP Dumm, MR Duvoort, WR Edwards, R Ehrlich, J Eisch, RW Ellsworth, PA Evenson, O Fadiran, AR Fazely, K Filimonov, MM Foerster, BD Fox, A Franckowiak, TK Gaisser, J Gallagher, R Ganugapati, H Geenen, L Gerhardt, A Goldschmidt, JA Goodman, R Gozzini, T Griesel, A Gross, S Grullon, RM Gunasingha, M Gurtner, A Hallgren, F Halzen, K Han, K Hanson, D Hardtke, R Hardtke, JE Hart, Y Hasegawa, T Hauschildt, D Hays, J Heise, K Helbing, M Hellwig, P Herquet, GC Hill, J Hodges, KD Hoffman, B Hommez, K Hoshina, D Hubert, B Hughey, PO Hulth, JP Hülss, K Hultqvist, S Hundertmark, M Inaba, A Ishihara, J Jacobsen, GS Japaridze

Abstract:

We present the results of the analysis of neutrino observations by the Antarctic Muon and Neutrino Detector Array (AMANDA) correlated with photon observations of more than 400 gamma-ray bursts (GRBs) in the northern hemisphere from 1997 to 2003. During this time period, AMANDA'S effective collection area for muon neutrinos was larger than that of any other existing detector. After the application of various selection criteria to our data, we expect ∼ 1 neutrino event and <2 background events. Based on our observations of zero events during and immediately prior to the GRBs in the data set, we set the most stringent upper limit on muon neutrino emission correlated with GRBs. Assuming a Waxman-Bahcall spectrum and incorporating all systematic uncertainties, our flux upper limit has a normalization at 1 PeVof E2Φv, ≤ 6.3 × 10-9 GeV cm-2 s-1 sr -1, with 90% of the events expected within the energy range of ∼ 10 TeV to ∼3 PeV The impact of this limit on several theoretical models of GRBs is discussed, as well as the future potential for detection of GRBs by next-generation neutrino telescopes. Finally, we briefly describe several modifications to this analysis in order to apply it to other types of transient point sources. © 2008. The American Astronomical Society. All rights reserved.

IceCube contributions to the XIV International Symposium on Very High Energy Cosmic Ray Interactions (ISVHECRI 2006) Weihai, China - August 15-22

NUCL PHYS B-PROC SUP 175 (2008) 407-408

Authors:

A Achterberg, M Ackermann, J Adams, J Ahrens, K Andeen, DW Atlee, JN Bahcall, X Bai, B Baret, SW Barwick, R Bay, K Beattie, T Becka, JK Becker, KH Becker, P Berghaus, D Berley, E Bernardini, D Bertrand, DZ Besson, E Blaufuss, DJ Boersma, C Bohm, J Bolmont, S Boser, O Botner, A Bouchta, J Braun, C Burgess, T Burgess, T Castermans, D Chirkin, B Christy, J Clem, DF Cowen, MV D'Agostino, A Davour, CT Day, C De Clercq, L Demirors, F Descamps, P Desiati, T DeYoung, JC Diaz-Velez, J Dreyer, JP Dumm, MR Duvoort, WR Edwards, R Ehrlich, J Eisch, RW Ellsworth, PA Evenson, O Fadiran, AR Fazely, T Feser, K Filimonov, BD Fox, TK Gaisser, J Gallagher, R Ganugapati, H Geenen, L Gerhardt, A Goldschmidt, JA Goodman, R Gozzini, S Grullon, A Gross, RM Gunasingha, M Gurtner, A Hallgren, F Halzen, K Han, K Hanson, D Hardtke, R Hardtke, T Harenberg, JE Hart, T Hauschildt, D Hays, J Heise, K Helbing, M Hellwig, P Herquet, GC Hill, J Hodges, KD Hoffman, B Hommez, K Hoshina, D Hubert, B Hughey, PO Hulth, K Hultqvist, S Hundertmark, JP Hulss, A Ishihara, J Jacobsen, GS Japaridze, H Johansson, A Jones, JM Joseph, KH Kampert, A Karle, H Kawai, JL Kelley, M Kestel, N Kitamura, SR Klein, S Klepser, G Kohnen, H Kolanoski, L Kopke, M Krasberg, K Kuehn, H Landsman, H Leich, D Leier, M Leuthold, I Liubarsky, J Lundberg, J Lunemann, J Madsen, K Mase, HS Matis, T McCauley, CP McParland, A Meli, T Messarius, P Meszaros, H Miyamoto, A Mokhtarani, T Montaruli, A Morey, R Morse, SM Movit, K Munich, R Nahnhauer, JW Nam, P Niessen, DR Nygren, H Ogelman, A Olivas, S Patton, C Pena-Garay, CP de los Heros, A Piegsa, D Pieloth, AC Pohl, R Porrata, J Pretz, PB Price, GT Przybylski, K Rawlins, S Razzaque, E Resconi, W Rhode, M Ribordy, A Rizzo, S Robbins, P Roth, C Rott, D Rutledge, D Ryckbosch, HG Sander, S Sarkar, S Schlenstedt, T Schmidt, D Schneider, D Seckel, SH Seo, S Seunarine, A Silvestri, AJ Smith, M Solarz, C Song, JE Sopher, GM Spiczak, C Spiering, M Stamatikos, T Stanev, P Steffen, T Stezelberger, RG Stokstad, MC Stoufer, S Stoyanov, EA Strahler, T Straszheim, KH Sulanke, GW Sullivan, TJ Sumner, I Taboada, O Tarasova, A Tepe, L Thollander, S Tilav, M Tluczykont, PA Toale, D Turcan, N van Eijndhoven, J Vandenbroucke, A Van Overloop, B Veigt, W Wagner, C Walck, H Waldmann, M Walter, YR Wang, C Wendt, CH Wiebusch, G Wikstrom, DR Williams, R Wischnewski, H Wissing, K Woschnagg, XW Xu, G Yodh, S Yoshida, JD Zornoza

Fine tuning and the ratio of tensor to scalar density fluctuations from cosmological inflation

JCAP 0810 (2008) 015-015

Authors:

Shaun Hotchkiss, Gabriel German, Graham G Ross, Subir Sarkar

SOLAR ENERGETIC PARTICLE SPECTRUM ON 2006 DECEMBER 13 DETERMINED BY IceTop

ASTROPHYSICAL JOURNAL LETTERS 689:1 (2008) L65-L68

Authors:

R Abbasi, M Ackermann, J Adams, M Ahlers, J Ahrens, K Andeen, J Auffenberg, X Bai, M Baker, B Baret, SW Barwick, R Bay, JL Bazo Alba, K Beattie, T Becka, JK Becker, KH Becker, P Berghaus, D Berley, E Bernardini, D Bertrand, DZ Besson, JW Bieber, E Blaufuss, DJ Boersma, C Bohm, J Bolmont, S Boeser, O Botner, J Braun, D Breder, T Burgess, T Castermans, D Chirkin, B Christy, J Clem, DF Cowen, MV D'Agostino, M Danninger, A Davour, CT Day, C De Clercq, L Demiroers, O Depaepe, F Descamps, P Desiati, G de Vries-Uiterweerd, T DeYoung, JC Diaz-Velez, J Dreyer, JP Dumm, MR Duvoort, WR Edwards, R Ehrlich, J Eisch, RW Ellsworth, O Engdegaard, S Euler, PA Evenson, O Fadiran, AR Fazely, K Filimonov, C Finley, MM Foerster, BD Fox, A Franckowiak, R Franke, TK Gaisser, J Gallagher, R Ganugapati, L Gerhardt, L Gladstone, A Goldschmidt, JA Goodman, R Gozzini, D Grant, T Griesel, A Gross, S Grullon, RM Gunasingha, M Gurtner, C Ha, A Hallgren, F Halzen, K Han, K Hanson, D Hardtke, R Hardtke, Y Hasegawa, J Heise, K Helbing, M Hellwig, P Herquet, S Hickford, GC Hill, KD Hoffman, K Hoshina, D Hubert, JP Huelss, PO Hulth, K Hultqvist, S Hundertmark, RL Imlay, M Inaba, A Ishihara, J Jacobsen, GS Japaridze, H Johansson, JM Joseph, KH Kampert, A Kappes, T Karg, A Karle, H Kawai, JL Kelley, J Kiryluk, F Kislat, SR Klein, S Klepser, G Kohnen, H Kolanoski, L Koepke, M Kowalski, T Kowarik, M Krasberg, K Kuehn, T Kuwabara, M Labare, K Laihem, H Landsman, R Lauer, H Leich, D Leier, A Lucke, J Lundberg, J Luenemann, J Madsen, R Maruyama, K Mase, HS Matis, CP McParland, K Meagher, A Meli, M Merck, T Messarius, P Meszaros, H Miyamoto, A Mohr, T Montaruli, R Morse, SM Movit, K Muenich, R Nahnhauer, JW Nam, P Niessen, DR Nygren, S Odrowski, A Olivas, M Olivo, M Ono, S Panknin, S Patton, C Perez de Los Heros, J Petrovic, A Piegsa, D Pieloth, AC Pohl, R Porrata, N Potthoff, J Pretz, PB Price, GT Przybylski, R Pyle, K Rawlins, S Razzaque, P Redl, E Resconi, W Rhode, M Ribordy, A Rizzo, WJ Robbins, J Rodrigues, P Roth, F Rothmaier, C Rott, C Roucelle, D Rutledge, D Ryckbosch, HG Sander, S Sarkar, K Satalecka, S Schlenstedt, T Schmidt, D Schneider, O Schultz, D Seckel, B Semburg, SH Seo, Y Sestayo, S Seunarine, A Silvestri, AJ Smith, C Song, GM Spiczak, C Spiering, T Stanev, T Stezelberger, RG Stokstad, MC Stoufer, S Stoyanov, EA Strahler, T Straszheim, KH Sulanke, GW Sullivan, Q Swillens, I Taboada, O Tarasova, A Tepe, S Ter-Antonyan, S Tilav, M Tluczykont, PA Toale, D Tosi, D Turcan, N van Eijndhoven, J Vandenbroucke, A Van Overloop, V Viscomi, C Vogt, B Voigt, C Walck, T Waldenmaier, H Waldmann, M Walter, C Wendt, S Westerhoff, N Whitehorn, CH Wiebusch, C Wiedemann, G Wikstroem, DR Williams, R Wischnewski, H Wissing, K Woschnagg, XW Xu, G Yodh, S Yoshida

Correlation of the highest-energy cosmic rays with the positions of nearby active galactic nuclei

ArXiv 0712.2843 (2007)

Abstract:

Data collected by the Pierre Auger Observatory provide evidence for anisotropy in the arrival directions of the cosmic rays with the highest energies, which are correlated with the positions of relatively nearby active galactic nuclei (AGN) \cite{science}. The correlation has maximum significance for cosmic rays with energy greater than ~ 6x10^{19}$ eV and AGN at a distance less than ~ 75 Mpc. We have confirmed the anisotropy at a confidence level of more than 99% through a test with parameters specified {\em a priori}, using an independent data set. The observed correlation is compatible with the hypothesis that cosmic rays with the highest energies originate from extra-galactic sources close enough so that their flux is not significantly attenuated by interaction with the cosmic background radiation (the Greisen-Zatsepin-Kuz'min effect). The angular scale of the correlation observed is a few degrees, which suggests a predominantly light composition unless the magnetic fields are very weak outside the thin disk of our galaxy. Our present data do not identify AGN as the sources of cosmic rays unambiguously, and other candidate sources which are distributed as nearby AGN are not ruled out. We discuss the prospect of unequivocal identification of individual sources of the highest-energy cosmic rays within a few years of continued operation of the Pierre Auger Observatory.

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