Measurement and Interpretation of UHECR Mass Composition at the Pierre Auger Observatory

作者：Eric William Mayotte, Adila Abdul Halim, P. Abreu, M. Aglietta, I. Allekotte, Kévin Almeida Cheminant, Alejandro Almela, Roberto Aloisio, Jaime Álvarez-Muñiz, Antonio Ambrosone, Juan Ammerman Yebra, Gioacchino Alex Anastasi, Luis A. Anchordoqui, Belén Andrada, Luciana Andrade Dourado, S. Andringa, Lorenzo Apollonio, C. Aramo, Enrico Arnone, Juan Carlos Arteaga Velázquez, P. Assis, Gualberto Avila, Emanuele Avocone, Alena Bakalová, Felicia Barbato, Adriel Bartz Mocellin, Jose A. Bellido, Corinne Bérat, Mario E. Bertaina, Marta Bianciotto, Peter L. Biermann, Virginia Binet, Kathrin Bismark, Teresa Bister, Jonathan Biteau, Jiří Blažek, Johannes Blümer, Martina Boháčová, Denise Boncioli, C. Bonifazi, Luan Bonneau Arbeletche, Nataliia Borodai, Jeffrey Brack, P. Gabriel Brichetto Orchera, Florian Lukas Briechle, A. Bueno, S. Buitink, Mario Buscemi, Max Büsken, Anthony Bwembya, K. S. Caballero‐Mora, Sergio Cabana-Freire, Lorenzo Caccianiga, Federico Campuzano, Jorge Caraça-Valente, R. Caruso, A. Castellina, Fernando Catalani, G. Cataldi, Lorenzo Cazon, Marcos Cerda, Berenika Čermáková, Alessandro Cermenati, J. A. Chinellato, J. Chudoba, L. Chytka, R. W. Clay, Agustín Cobos Cerutti, Roberta Colalillo, R. Conceição, Giovanni Consolati, Matteo Conte, Fabio Convenga, Diego Correia dos Santos, Pedro J. Costa, C. E. Covault, M. Cristinziani, Carlo Salvattore Cruz Sanchez, S. Dasso, K. Daumiller, B. R. Dawson, Rogerio M. de Almeida, Eric-Teunis de Boone, Beatriz de Errico, Joaquín de Jesús, S. J. de Jong, João de Mello Neto, I. De Mitri, Jaime de Oliveira, Danelise de Oliveira Franco, Francesco de Palma, Vitor de Souza, Emanuele De Vito, Antonino Del Popolo, Olivier Deligny, Nikolas Denner, Luca Deval, Armando di Matteo, C. Dobrigkeit, Juan Carlos D'Olivo, Luis Miguel Domingues Mendes, Qader Dorosti, Joao dos Anjos, Rita Cassia dos Anjos, Jan Ebr, Fiona H. Ellwanger, Ralph Engel, Italo Epicoco, M. Erdmann, Alberto Etchegoyen, Carmelo Evoli, H. Falcke, Glennys R. Farrar, A. C. Fauth, Tim Fehler, Fridtjof Feldbusch, Alexandra Fernandes, Mateo Fernandez, Brian Fick, Juan Manuel Figueira, Paul Filip, Andrej Filipčič, Thomas Fitoussi, Benjamin Flaggs, Tomáš Fodran, Antonio Franco, Milton Freitas, Toshihiro Fujii, Alan Fuster, Cristina Galea, B. Garćıa, Chloé Gaudu, Piera Luisa Ghia, Ugo GIACCARI, Fabian Gobbi, Fernando Gollan, G. Golup, M. Gómez Berisso, Primo F. Gómez Vitale, Juan Pablo Gongora, Juan Manuel Gonzalez, Nicolás Martín González, Dariusz Gora, A. Gorgi, Marvin Gottowik, F. Guarino, Germano Guedes, Lukas Gülzow, Steffen Hahn, P. Hamal, Matías Rolf Hampel, Patricia María Hansen, Violet M. Harvey, A. Haungs, T. Hebbeker, C. Hojvat, J.R. Hörandel, Pavel Horváth, Miroslav Hrabovský, T. Huege, A. Insolia, Paula Gina Isar, Mohamed Ismaiel, Petr Janeček, Vlastimil Jílek, K.‐H. Kampert, B. Keilhauer, Abha Khakurdikar, Varada Varma Kizakke Covilakam, H.O. Klages, Matthias Kleifges, Jelena Köhler, Frederik Krieger, Margita Kubátová, Norbert Kunka, Bruno L. Lago, Niklas Langner, Nicolas Leal, Marcelo Augusto Leigui de Oliveira, Yago Lema-Capeans, A. Letessier‐Selvon, Isabelle Lhenry-Yvon, L. Lopes, Jon Paul Lundquist, M. Mallamaci, Dušan Mandát, P. Mantsch, Federico Maria Mariani, Analisa Mariazzi, Ioana Codrina Maris, G. Marsella, Daniele Martello, Sara Martinelli, Miguel A. Martins, Hermann-Josef Mathes, J. Matthews, Giorgio Matthiae, Sonja Mayotte, Peter Mazur, Gustavo Medina‐Tanco, Janning Meinert, Diego Melo, Alexander Menshikov, Carmen Merx, Stanislav Michal, María Isabel Micheletti, L. Miramonti, Megha Mogarkar, Silvia Mollerach, F. Montanet, Leonel Morejón, Katharine Mulrey, R. Mussa, Wilson M. Namasaka, Shefali Negi, L. Nellen, Khoa Nguyen, Gabriela Nicora, Marcus Niechciol, Dave Nitz, Dalibor Nosek, Alexander Novikov, Vladimír Novotný, Libor Nožka, Achille Nucita, Luis A. Núñez, José Ochoa, Cainã Oliveira, Leo Östman, M. Palatka, Juan Pallotta, Shayoni Panja, G. Parente, Therese Paulsen, Jannis Pawlowsky, M. Pech, Jan Pękala, Rodrigo Pelayo, Vincent Pelgrims, Luiz Augusto Pereira, Edyvânia Emily Pereira Martins, Carmina Pérez Bertolli, Lorenzo Perrone, S. Petrera, Camilla Petrucci, T. Pierog, Mário Pimenta, Manuel Platino, Bjarni Pont, Mohsen Pourmohammad Shahvar, Paolo Privitera, Chaitanya Priyadarshi, Michael Prouza, Krzysztof Pytel, Sven Querchfeld, J. Rautenberg, Diego Ravignani, João Vítor Reginatto Akim, Alex Reuzki, J. Řídký, Felix Riehn, Markus Risse, V. Rizi, Ezequiel Rodriguez, Gonzalo Rodriguez Fernandez, Jorge Rubén Rodriguez Rojo, Simone Rossoni, M. Roth, Esteban Roulet, Adrián Rovero, A. Sǎftoiu, Mohit Saharan, F. Salamida, Humberto Ibarguen Salazar, Gaetano Salina, Pranav Sampathkumar, Nicolas San Martin, Jose Sanabria Gomez, Federico Andrés Sánchez, Edivaldo Moura Santos, Eva Santos, F. Sarazin, R. Sarmento, Ricardo Sato, Pierpaolo Savina, Viviana Scherini, H. Schieler, Martin Schimassek, Michael Schimp, David Schmidt, O. Schölten, Harm Schoorlemmer, Petr Schovanek, Frank Schröder, Josina Schulte, Tobias Schulz, Sergio J Sciutto, Marina Scornavacche, Adrian Sedoski, A. Segreto, Srijan Sehgal, Shima Ujjani Shivashankara, G. Sigl, Katarína Simkova, F. Simon, Radomir Šmída, Paul Sommers, Ruben Squartini, Maximilian Stadelmaier, S. Stanič, Jarosław Stasielak, Patrick Stassi, Simon Strähnz, Maximilian Straub, Tiina Suomijärvi, A. D. Supanitsky, Zuzana Svozilikova, Karolina Syrokvas, Zbigniew Szadkowski, Fedor Tairli, Matteo Tambone, A. Tapia, Carla Taricco, Charles Timmermans, Olena Tkachenko, Petr Tobiška, Carlos J. Todero Peixoto, B. Tomé, Andres Travaini, P. Trávnı́ček, Matias Jorge Tueros, M. Unger, Rukije Uzeiroska, Lukáš Vaclavek, Martin Vacula, Igor Vaiman, Jose F. Valdés Galicia, Laura Valore, Pim van Dillen, Enrique Varela, Veronika Vašíčková, Adriana Vásquez-Ramírez, Darko Veberič, Indira D. Vergara Quispe, Stef Verpoest, V. Verzi, J. Vícha, Jacco Vink, S. Vorobiov, Jhansi Bhavani Vuta, Clara Keiko Oliveira Watanabe, Alan Watson, Andreas Weindl, Melanie Weitz, Lawrence Wiencke, H. Wilczyński, Brian Wundheiler, Bin Yue, Alexey Yushkov, E. Zas, Danilo Zavrtanik, Marko Zavrtanik · 年份：2025 · DOI：10.22323/1.501.0331 · 被引用次数：1 · 研究领域：Superconducting Materials and Applications、Particle Accelerators and Free-Electron Lasers、Particle physics theoretical and experimental studies

The Pierre Auger Observatory has driven the field of ultra-high-energy cosmic ray (UHECR) physics, producing several groundbreaking observations over the last 20 years. One of the most striking findings has been the complex evolution of UHECR mass composition, as revealed by detailed analyses of observables such as the depth of shower maximum ($X_{\rm max}$) and the muon content of showers. As more data are collected and sophisticated analyses are undertaken, not only are new fine details emerging, but the general picture of UHECR mass composition is becoming increasingly robust. This contribution presents recent results on the mass composition of UHECRs derived from surface, fluorescence, and radio detectors. Together with other key findings from the Observatory, these results converge to present a coherent picture of UHECR mass composition, effectively ruling out proton dominance and challenging the interpretation of the observed flux features as purely proton-induced propagation effects. To finish the contribution, we compare the $X_{\rm max}$ data from the southern and northern equatorial bands of the exposure of the Pierre Auger Observatory fluorescence detector to evaluate the possibility of changes in composition as a function of declination.