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arXiv · 1504.05397

An improved limit to the diffuse flux of ultra-high energy neutrinos from the Pierre Auger Observatory

The Pierre Auger Collaboration·Alexander Aab·Pedro Abreu·Marco Aglietta·Eun-Joo Ahn·Imen Al Samarai·Ivone Albuquerque·Ingomar Allekotte·Patrick Allison·Alejandro Almela·Jesus Alvarez Castillo·Jaime Alvarez-Muñiz·Rafael Alves Batista·Michelangelo Ambrosio·Amin Aminaei·Luis Anchordoqui·Sofia Andringa·Carla Aramo·Victor Manuel Aranda·Fernando Arqueros·Nicusor Arsene·Hernán Gonzalo Asorey·Pedro Assis·Julien Aublin·Maximo Ave·Michel Avenier·Gualberto Avila·Nafiun Awal·Alina Mihaela Badescu·Kerri B Barber·Julia Bäuml·Colin Baus·Jim Beatty·Karl Heinz Becker·Jose A Bellido·Corinne Berat·Mario Edoardo Bertaina·Xavier Bertou·Peter Biermann·Pierre Billoir·Simon G Blaess·Alberto Blanco·Miguel Blanco·Carla Bleve·Hans Blümer·Martina Boháčová·Denise Boncioli·Carla Bonifazi·Nataliia Borodai·Jeffrey Brack·Iliana Brancus·Ariel Bridgeman·Pedro Brogueira·William C Brown·Peter Buchholz·Antonio Bueno·Stijn Buitink·Mario Buscemi·Karen S Caballero-Mora·Barbara Caccianiga·Lorenzo Caccianiga·Marina Candusso·Laurentiu Caramete·Rossella Caruso·Antonella Castellina·Gabriella Cataldi·Lorenzo Cazon·Rosanna Cester·Alan G Chavez·Andrea Chiavassa·Jose Augusto Chinellato·Jiri Chudoba·Marco Cilmo·Roger W Clay·Giuseppe Cocciolo·Roberta Colalillo·Alan Coleman·Laura Collica·Maria Rita Coluccia·Ruben Conceição·Fernando Contreras·Mathew J Cooper·Alain Cordier·Stephane Coutu·Corbin Covault·James Cronin·Richard Dallier·Bruno Daniel·Sergio Dasso·Kai Daumiller·Bruce R Dawson·Rogerio M de Almeida·Sijbrand J de Jong·Giuseppe De Mauro·Joao de Mello Neto·Ivan De Mitri·Jaime de Oliveira·Vitor de Souza·Luis del Peral·Olivier Deligny

Abstract

Neutrinos in the cosmic ray flux with energies near 1 EeV and above are detectable with the Surface Detector array of the Pierre Auger Observatory. We report here on searches through Auger data from 1 January 2004 until 20 June 2013. No neutrino candidates were found, yielding a limit to the diffuse flux of ultra-high energy neutrinos that challenges the Waxman-Bahcall bound predictions. Neutrino identification is attempted using the broad time-structure of the signals expected in the SD stations, and is efficiently done for neutrinos of all flavors interacting in the atmosphere at large zenith angles, as well as for "Earth-skimming" neutrino interactions in the case of tau neutrinos. In this paper the searches for downward-going neutrinos in the zenith angle bins $60^\circ-75^\circ$ and $75^\circ-90^\circ$ as well as for upward-going neutrinos, are combined to give a single limit. The $90\%$ C.L. single-flavor limit to the diffuse flux of ultra-high energy neutrinos with an $E^{-2}$ spectrum in the energy range $1.0 \times 10^{17}$ eV - $2.5 \times 10^{19}$ eV is $E_\nu^2 dN_\nu/dE_\nu < 6.4 \times 10^{-9}~ {\rm GeV~ cm^{-2}~ s^{-1}~ sr^{-1}}$.

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The Pierre Auger Collaboration, Alexander Aab, Pedro Abreu, Marco Aglietta, Eun-Joo Ahn, Imen Al Samarai, Ivone Albuquerque, Ingomar Allekotte, Patrick Allison, Alejandro Almela, Jesus Alvarez Castillo, Jaime Alvarez-Muñiz, Rafael Alves Batista, Michelangelo Ambrosio, Amin Aminaei, Luis Anchordoqui, Sofia Andringa, Carla Aramo, Victor Manuel Aranda, Fernando Arqueros, Nicusor Arsene, Hernán Gonzalo Asorey, Pedro Assis, Julien Aublin, Maximo Ave, Michel Avenier, Gualberto Avila, Nafiun Awal, Alina Mihaela Badescu, Kerri B Barber, Julia Bäuml, Colin Baus, Jim Beatty, Karl Heinz Becker, Jose A Bellido, Corinne Berat, Mario Edoardo Bertaina, Xavier Bertou, Peter Biermann, Pierre Billoir, Simon G Blaess, Alberto Blanco, Miguel Blanco, Carla Bleve, Hans Blümer, Martina Boháčová, Denise Boncioli, Carla Bonifazi, Nataliia Borodai, Jeffrey Brack, Iliana Brancus, Ariel Bridgeman, Pedro Brogueira, William C Brown, Peter Buchholz, Antonio Bueno, Stijn Buitink, Mario Buscemi, Karen S Caballero-Mora, Barbara Caccianiga, Lorenzo Caccianiga, Marina Candusso, Laurentiu Caramete, Rossella Caruso, Antonella Castellina, Gabriella Cataldi, Lorenzo Cazon, Rosanna Cester, Alan G Chavez, Andrea Chiavassa, Jose Augusto Chinellato, Jiri Chudoba, Marco Cilmo, Roger W Clay, Giuseppe Cocciolo, Roberta Colalillo, Alan Coleman, Laura Collica, Maria Rita Coluccia, Ruben Conceição, Fernando Contreras, Mathew J Cooper, Alain Cordier, Stephane Coutu, Corbin Covault, James Cronin, Richard Dallier, Bruno Daniel, Sergio Dasso, Kai Daumiller, Bruce R Dawson, Rogerio M de Almeida, Sijbrand J de Jong, Giuseppe De Mauro, Joao de Mello Neto, Ivan De Mitri, Jaime de Oliveira, Vitor de Souza, Luis del Peral, Olivier Deligny. 2015-04-21. An improved limit to the diffuse flux of ultra-high energy neutrinos from the Pierre Auger Observatory. https://doi.org/10.1103/physrevd.91.092008

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