Energy Estimation of Cosmic Rays with the Engineering Radio Array of the Pierre Auger Observatory

2015Aug
Authors: 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, Gioacchino Alex Anastasi, Luis Anchordoqui, Sofia Andringa, Carla Aramo, Fernando Arqueros, Nicusor Arsene, Hernán Gonzalo Asorey, Pedro Assis, Julien Aublin, Gualberto Avila, Nafiun Awal, Alina Mihaela Badescu, 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, Jiri Blazek, Carla Bleve, Hans Blümer, Martina Boháčová, Denise Boncioli, Carla Bonifazi, Nataliia Borodai, Jeffrey Brack, Iliana Brancus, Thomas Bretz, Ariel Bridgeman, Pedro Brogueira, 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, Niraj Dhital, Claudio Di Giulio, Armando Di Matteo, Johana Chirinos Diaz, Mary Lucia Díaz Castro, Francisco Diogo, Carola Dobrigkeit, Wendy Docters, Juan Carlos D'Olivo, Alexei Dorofeev, Qader Dorosti Hasankiadeh, Rita dos Anjos, Maria Teresa Dova, Jan Ebr, Ralph Engel, Martin Erdmann, Mona Erfani, Carlos O. Escobar, Joao Espadanal, Alberto Etchegoyen, Heino Falcke, Ke Fang, Glennys Farrar, Anderson Fauth, Norberto Fazzini, Andrew P. Ferguson, Brian Fick, Juan Manuel Figueira, Alberto Filevich, Andrej Filipčič, Octavian Fratu, Martín Miguel Freire, Toshihiro Fujii, Beatriz García, Diego Garcia-Gamez, Diego Garcia-Pinto, Florian Gate, Hartmut Gemmeke, Alexandru Gherghel-Lascu, Piera Luisa Ghia, Ugo Giaccari, Marco Giammarchi, Maria Giller, Dariusz Głas, Christian Glaser, Henry Glass, Geraldina Golup, Mariano Gómez Berisso, Primo F. Gómez Vitale, Nicolás González, Ben Gookin, Jacob Gordon, Alessio Gorgi, Peter Gorham, Philippe Gouffon, Nathan Griffith, Aurelio Grillo, Trent D. Grubb, Fausto Guarino, Germano Guedes, Matías Rolf Hampel, Patricia Hansen, Diego Harari, Thomas A. Harrison, Sebastian Hartmann, John Harton, Andreas Haungs, Thomas Hebbeker, Dieter Heck, Philipp Heimann, Alexander E. Herve, Gary C. Hill, Carlos Hojvat, Nicholas Hollon, Ewa Holt, Piotr Homola, Jörg Hörandel, Pavel Horvath, Miroslav Hrabovský, Daniel Huber, Tim Huege, Antonio Insolia, Paula Gina Isar, Ingolf Jandt, Stefan Jansen, Cecilia Jarne, Jeffrey A. Johnsen, Mariela Josebachuili, Alex Kääpä, Olga Kambeitz, Karl Heinz Kampert, Peter Kasper, Igor Katkov, Bianca Keilhauer, Ernesto Kemp, Roger Kieckhafer, Hans Klages, Matthias Kleifges, Jonny Kleinfeller, Raphael Krause, Nicole Krohm, Daniel Kuempel, Gasper Kukec Mezek, Norbert Kunka, Alaa Metwaly Kuotb Awad, Danielle LaHurd, Luca Latronico, Robert Lauer, Markus Lauscher, Pascal Lautridou, Sandra Le Coz, Didier Lebrun, Paul Lebrun, Marcelo Augusto Leigui de Oliveira, Antoine Letessier-Selvon, Isabelle Lhenry-Yvon, Katrin Link, Luis Lopes, Rebeca López, Aida López Casado, Karim Louedec, Agustin Lucero, Max Malacari, Manuela Mallamaci, Jennifer Maller, Dusan Mandat, Paul Mantsch, Analisa Mariazzi, Vincent Marin, Ioana Mariş, Giovanni Marsella, Daniele Martello, Humberto Martinez, Oscar Martínez Bravo, Diane Martraire, Jimmy Masías Meza, Hermann-Josef Mathes, Sebastian Mathys, James Matthews, John Matthews, Giorgio Matthiae, Daniela Maurizio, Eric Mayotte, Peter Mazur, Carlos Medina, Gustavo Medina-Tanco, Rebecca Meissner, Victor Mello, Diego Melo, Alexander Menshikov, Stefano Messina, Maria Isabel Micheletti, Lukas Middendorf, Ignacio A. Minaya, Lino Miramonti, Bogdan Mitrica, Laura Molina-Bueno, Silvia Mollerach, François Montanet, Carlo Morello, Miguel Mostafá, Celio A. Moura, Marcio Aparecido Muller, Gero Müller, Sarah Müller, Sergio Navas, Petr Necesal, Lukas Nellen, Anna Nelles, Jens Neuser, Phong H. Nguyen, Mihai Niculescu-Oglinzanu, Marcus Niechciol, Lukas Niemietz, Tim Niggemann, Dave Nitz, Dalibor Nosek, Vladimir Novotny, Lyberis Nožka, Luis Núñez, Livingstone Ochilo, Foteini Oikonomou, Angela Olinto, Noelia Pacheco, Daniel Pakk Selmi-Dei, Miroslav Palatka, Juan Pallotta, Philipp Papenbreer, Gonzalo Parente, Alejandra Parra, Thomas Paul, Miroslav Pech, Jan Pękala, Rodrigo Pelayo, Iuri Pepe, Lorenzo Perrone, Emily Petermann, Christine Peters, Sergio Petrera, Yevgeniy Petrov, Jamyang Phuntsok, Ricardo Piegaia, Tanguy Pierog, Pablo Pieroni, Mário Pimenta, Valerio Pirronello, Manuel Platino, Matthias Plum, Alessio Porcelli, Czeslaw Porowski, Raul Ribeiro Prado, Paolo Privitera, Michael Prouza, Eduardo J Quel, Sven Querchfeld, Sean Quinn, Julian Rautenberg, Olivier Ravel, Diego Ravignani, Darius Reinert, Benoît Revenu, Jan Ridky, Markus Risse, Pablo Ristori, Vincenzo Rizi, Washington Rodrigues de Carvalho, Jorge Rubén Rodriguez Rojo, Maria Dolores Rodríguez-Frías, Dmytro Rogozin, Jaime Rosado, Markus Roth, Esteban Roulet, Adrian Rovero, Steven J. Saffi, Alexandra Saftoiu, Humberto Salazar, Ahmed Saleh, Francisco Salesa Greus, Gaetano Salina, Jose Sanabria Gomez, Federico Sánchez, Patricia Sanchez-Lucas, Edivaldo Moura Santos, Eva Santos, Fred Sarazin, Biswaijt Sarkar, Raul Sarmento, Christian Sarmiento-Cano, Ricardo Sato, Carlos Scarso, Markus Schauer, Viviana Scherini, Harald Schieler, David Schmidt, Olaf Scholten, Harm Schoorlemmer, Petr Schovánek, Frank G. Schröder, Alexander Schulz, Johannes Schulz, Johannes Schumacher, Sergio Sciutto, Alberto Segreto, Mariangela Settimo, Amir Shadkam, Ronald C. Shellard, Guenter Sigl, Octavian Sima, Andrzej Śmiałkowski, Radomir Šmída, Gregory Snow, Paul Sommers, Sebastian Sonntag, J. Sorokin, Ruben Squartini, Yogendra N. Srivastava, Denis Stanca, Samo Stanič, James Stapleton, Jaroslaw Stasielak, Maurice Stephan, Anne Stutz, Federico Suarez, Mauricio Suarez Durán, Tiina Suomijärvi, A. Daniel Supanitsky, Michael Sutherland, John Swain, Zbigniew Szadkowski, Oscar Alejandro Taborda, Alex Tapia, Andreas Tepe, Vanessa Menezes Theodoro, Omar Tibolla, Charles Timmermans, Carlos J. Todero Peixoto, Gabriel Toma, Lenka Tomankova, Bernardo Tomé, Aurelio Tonachini, Guillermo Torralba Elipe, Diego Torres Machado, Petr Travnicek, Marta Trini, Ralf Ulrich, Michael Unger, Martin Urban, Jose F. Valdés Galicia, Ines Valiño, Laura Valore, Guus van Aar, Patrick van Bodegom, Ad M. van den Berg, Sjoert van Velzen, Arjen van Vliet, Enrique Varela, Bernardo Vargas Cárdenas, Gary Varner, Rafael Vasquez, Jose R. Vázquez, Ricardo Vázquez, Darko Veberič, Valerio Verzi, Jakub Vicha, Mariela Videla, Luis Villaseñor, Brian Vlcek, Serguei Vorobiov, Hernan Wahlberg, Oscar Wainberg, David Walz, Alan Watson, Marc Weber, Klaus Weidenhaupt, Andreas Weindl, Christoph Welling, Felix Werner, Allan Widom, Lawrence Wiencke, Henryk Wilczyński, Tobias Winchen, David Wittkowski, Brian Wundheiler, Sarka Wykes, Lili Yang, Tolga Yapici, Alexey Yushkov, Enrique Zas, Danilo Zavrtanik, Marko Zavrtanik, Arnulfo Zepeda, Benedikt Zimmermann, Michael Ziolkowski, Francesca Zuccarello

The Auger Engineering Radio Array (AERA) is part of the Pierre Auger Observatory and is used to detect the radio emission of cosmic-ray air showers. These observations are compared to the data of the surface detector stations of the Observatory, which provide well-calibrated information on the cosmic-ray energies and arrival directions. The response of the radio stations in the 30 to 80 MHz regime has been thoroughly calibrated to enable the reconstruction of the incoming electric field. For the latter, the energy density is determined from the radio pulses at each observer position and is interpolated using a two dimensional function that takes into account signal asymmetries due to interference between the geomagnetic and charge excess emission components. The spatial integral over the signal distribution gives a direct measurement of the energy transferred from the primary cosmic ray into radio emission in the AERA frequency range. We measure 15.8 MeV of radiation energy for a 1 EeV air shower arriving perpendicularly to the geomagnetic field. This radiation energy -- corrected for geometrical effects -- is used as a cosmic-ray energy estimator. Performing an absolute energy calibration against the surface-detector information, we observe that this radio-energy estimator scales quadratically with the cosmic-ray energy as expected for coherent emission. We find an energy resolution of the radio reconstruction of 22% for the data set and 17% for a high-quality subset containing only events with at least five radio stations with signal.

Comments: Submitted to Phys. Rev. D

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