← Back to cohort
Energy Spectrum of Ultrahigh-Energy Cosmic Rays across Declinations <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"> <mml:mo>−</mml:mo> <mml:mn>9</mml:mn> <mml:mn>0</mml:mn> <mml:mi>°</mml:mi> </mml:math> to <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"> <mml:mo>+</mml:mo> <mml:mn>44.8</mml:mn> <mml:mi>°</mml:mi> </mml:math> as Measured at the Pierre Auger Observatory
Adila Abdul Halim, P. Abreu, M. Aglietta, I. Allekotte, Kévin Almeida Cheminant, A. Almela, Roberto Aloisio, Jaime Álvarez-Muñiz, Antonio Ambrosone, Juan Ammerman Yebra, G. A. Anastasi, L. Anchordoqui, B. Andrada, Luciana Andrade Dourado, S. Andringa, L. Apollonio, C. Aramo, E. Arnone, Juan Carlos Arteaga Velázquez, P. Assis, G. Ávila, E. Avocone, Alena Bakalová, F. Barbato, Adriel Bartz Mocellin, J. A. Bellido, C. Berat, M. E. Bertaina, Marta Bianciotto, Peter L. Biermann, Virginia Binet, K. Bismark, Teresa Bister, Jonathan Biteau, Jiří Blažek, J. Blümer, M. Boháčová, Denise Boncioli, C. Bonifazi, Luan Bonneau Arbeletche, Nataliia Borodai, J. Brack, P. G. Brichetto Orchera, F. L. Briechle, A. Bueno, S. Buitink, Mario Buscemi, M. Büsken, Anthony Bwembya, K. S. Caballero‐Mora, Sergio Cabana-Freire, Lorenzo Caccianiga, F. Campuzano, Jorge Caraça-Valente, R. Caruso, A. Castellina, Fernando Catalani, G. Cataldi, L. Cazon, M. Cerda, Berenika Čermáková, A. Cermenati, J. A. Chinellato, J. Chudoba, L. Chytka, R. W. Clay, A. C. Cobos Cerutti, R. Colalillo, R. Conceição, Giovanni Consolati, Marcelo Conte, Fabio Convenga, Diego Correia dos Santos, P. J. Costa, C. E. Covault, M. Cristinziani, Carlo Salvattore Cruz Sanchez, S. Dasso, K. Daumiller, B. R. Dawson, R. M. de Almeida, E.-T. de Boone, Beatriz de Errico, J. de Jesús, S. J. de Jong, I. De Mitri, J. de Oliveira, Danelise de Oliveira Franco, Francesco Palma, Emanuele De Vito, A. Del Popolo, Olivier Deligny, N. Denner, L. Deval, Armando di Matteo, C. Dobrigkeit, Juan Carlos D’Olivo, Luis Miguel Domingues Mendes, Q. Dorosti, J. C. dos Anjos, R. C. dos Anjos, Jan Ebr, Fiona H. Ellwanger, R. Engel, I. Epicoco, M. Erdmann, A. Etchegoyen, Carmelo Evoli, H. Falcke, G. Farrar, A. C. Fauth, Tim Fehler, F. Feldbusch, A. Fernandes, Marcos Fernández, B. Fick, J. M. Figueira, P. Filip, A. Filipčič, T. Fitoussi, Benjamin Flaggs, Tomáš Fodran, Antonio Franco, M. Freitas, Toshihiro Fujii, A. Fuster, C. Galea, B. Garćıa, Chloé Gaudu, P. L. Ghia, U. Giaccari, Fabian Gobbi, Fernando Gollan, G. Golup, M. Gómez Berisso, P. F. Gómez Vitale, J. P. Gongora, Juan Manuel González, Nicolás Martín González, D. Góra, A. Gorgi, M. Gottowik, F. Guarino, G. P. Guedes, E. Guido, Lukas Gülzow, Steffen Hahn, P. Hamal, Matías Rolf Hampel, P. H. 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, P. Janecek, Vlastimil Jílek, K.‐H. Kampert, B. Keilhauer, A. Khakurdikar, Varada Varma Kizakke Covilakam, H. O. Klages, M. Kleifges, Jan Köhler, F. Krieger, Margita Kubátová, N. Kunka, Bruno L. Lago, Niklas Langner, Nicolas Leal, M. A. Leigui de Oliveira, Yago Lema-Capeans, A. Letessier‐Selvon, I. Lhenry-Yvon, L. Lopes, Jon Paul Lundquist, M. Mallamaci, Dušan Mandát, P. Mantsch, F. M. Mariani, A. G. Mariazzi, Ioana Codrina Mariş, G. Marsella, D. Martello, S. Martinelli, Miguel A. Martins, Hermann-Josef Mathes, J. Matthews, G. Matthiae, Eric William Mayotte, S. Mayotte, P. O. Mazur, G. Medina-Tanco, Jill Meinert, D. Melo, A. Menshikov, Carmen Merx, S. Michal, M. I. Micheletti, L. Miramonti, Megha Mogarkar, S. Mollerach, F. Montanet, Leonel Morejón, Katharine Mulrey, R. Mussa, W. M. Namasaka, S. Negi, L. Nellen, K. Nguyen, Gabriela Nicora, Marcus Niechciol, D. Nitz, Dalibor Nosek, A. Novikov, Vladimír Novotný, L. Nožka, Achille Nucita, Luis A. Núñez, José Ochoa, C. Oliveira, L. Östman, M. Palatka, J. Pallotta, Subhash Chandra Panja, G. Parente, T. Paulsen, J. Pawlowsky, M. Pech, Jan Pękala, R. Pelayo, Vincent Pelgrims, Luiz Augusto Pereira, E. E. Pereira Martins, C. Pérez Bertolli, L. Perrone, S. Petrera, C. Petrucci, T. Pierog, M. Pimenta, M. Platino, Bjarni Pont, Mohsen Pourmohammad Shahvar, P. Privitera, C. Priyadarshi, M. Prouza, K. Pytel, S. Querchfeld, J. Rautenberg, D. Ravignani, João Vítor Reginatto Akim, Alex Reuzki, J. Řídký, Felix Riehn, Markus Risse, V. Rizi, E. Rodrı́guez, Gonzalo Rodriguez Fernandez, Juan Rojo, Simone Rossoni, M. Roth, E. Roulet, A.C. Rovero, A. Sǎftoiu, M. Saharan, F. Salamida, G. Salina, P. Sampathkumar, Nicolas San Martin, Jose Sanabria Gomez, F. Sánchez, Eva Santos, Edivaldo Moura Santos, F. Sarazin, R. Sarmento, R. Sato, P. Savina, Viviana Scherini, H. Schieler, Martin Schimassek, M. Schimp, David Schmidt, O. Schölten, H. Schoorlemmer, Petr Schovánek, Frank Schröder, J. Schulte, T. Schulz, S. J. Sciutto, Marina Scornavacche, Adrian Sedoski, A. Segreto, S. Sehgal, S. U. Shivashankara, G. Sigl, Katarína Simkova, F. Simon, Radomir Šmída, P. Sommers, R. Squartini, Maximilian Stadelmaier, S. Stanič, Jarosław Stasielak, Patrick Stassi, S. Strähnz, M. Straub, T. Suomijärvi, A. D. Supanitsky, Zuzana Svozilikova, Karolina Syrokvas, Zbigniew Szadkowski, Fedor Tairli, Matteo Tambone, A. Tapia, C. Taricco, C. Timmermans, Olena Tkachenko, P. Tobiska, 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, V. Vašíčková, A. Vásquez-Ramírez, Darko Veberič, I. D. Vergara Quispe, Stef Verpoest, V. Verzi, J. Vícha, Jacco Vink, S. Vorobiov, C. Watanabe, A. A. Watson, A. Weindl, Melanie Weitz, L. Wiencke, H. Wilczyński, B. Wundheiler, Bin Yue, Alexey Yushkov, E. Zas, D. Zavrtanik, M. Zavrtanik
Bibliographic record
VenuePhysical Review Letters · 2025
Typearticle
Languageen
FieldPhysics and Astronomy
TopicAstrophysics and Cosmic Phenomena
Canadian institutionsInstitute of Particle Physics
FundersNextGenerationEUHORIZON EUROPE Marie Sklodowska-Curie ActionsInstitut Lagrange de ParisInstitut National de Physique Nucléaire et de Physique des ParticulesAgencia Estatal de InvestigaciónAgencia Nacional de Promoción Científica y TecnológicaHelmholtz Alliance for Astroparticle PhysicsCentre de Calcul de Régional ROMEOJunta de AndalucíaMinistero dell'Università e della RicercaHelmholtz-GemeinschaftXunta de GaliciaFinanciadora de Estudos e ProjetosUnitatea Executiva pentru Finantarea Invatamantului Superior, a Cercetarii, Dezvoltarii si InovariiAustralian Research CouncilMinistério da Ciência, Tecnologia, Inovações e ComunicaçõesIstituto Nazionale di AstrofisicaUniversidad Nacional Autónoma de MéxicoEuropean Regional Development FundCentre National de la Recherche ScientifiqueU.S. Department of EnergyFundação Carlos Chagas Filho de Amparo à Pesquisa do Estado do Rio de JaneiroNarodowe Centrum NaukiFonds De La Recherche Scientifique - FNRSConselho Nacional de Desenvolvimento Científico e TecnológicoMinisterstwo Edukacji i NaukiJavna Agencija za Raziskovalno Dejavnost RSConseil Régional, Île-de-FranceMinisterium für Wissenschaft, Forschung und Kunst Baden-WürttembergInstitut national des sciences de l'UniversFonds Wetenschappelijk OnderzoekMinisterie van Onderwijs, Cultuur en WetenschapMinisterium für Kultur und Wissenschaft des Landes Nordrhein-WestfalenGrantová Agentura České RepublikyConsejo Nacional de Investigaciones Científicas y TécnicasMinisterstvo Školství, Mládeže a TělovýchovyBundesministerium für Bildung und ForschungFundação para a Ciência e a TecnologiaUnited Nations Educational, Scientific and Cultural OrganizationDeutsche ForschungsgemeinschaftChinese Academy of SciencesNederlandse Organisatie voor Wetenschappelijk OnderzoekDirección General de Asuntos del Personal Académico, Universidad Nacional Autónoma de MéxicoMinisterio de Ciencia e InnovaciónConsejo Nacional de Ciencia y TecnologíaMinistero degli Affari Esteri e della Cooperazione InternazionaleAgence Nationale de la RechercheGrainger FoundationEuropean CommissionFundação de Amparo à Pesquisa do Estado de São PauloComisión Nacional de Energía Atómica, Gobierno de ArgentinaMinisterul Cercetării, Inovării şi DigitalizăriiInstituto Nazionale di Fisica NucleareCorporation for National and Community ServiceNational Science Foundation
KeywordsDeclinationPierre Auger ObservatoryCosmic rayObservatoryRight ascensionSpectral lineAugerSky
Abstract
The energy spectrum of cosmic rays above 2.5 EeV has been measured across the declination range -90°≤δ≤+44.8° using ∼310 000 events accrued at the Pierre Auger Observatory from an exposure of (104 900±3 100) km^{2} sr yr. No significant variations of energy spectra with declination are observed, after allowing or not for nonuniformities across the sky arising from the well-established dipolar anisotropies in the arrival directions of ultrahigh-energy cosmic rays. The instep feature in the spectrum at ≃10 EeV reported previously is now established at a significance above 5σ. Within the statistics, the energy spectra are indistinguishable across declinations so disfavoring an origin for the instep from a few distinctive sources.
Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.
How this classification was reachedexpand
Full frame machine prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. The Gemma side is a direct model label for every work in the frame, read from the title-only record. The Codex side is a classifier learned from the 10,348 direct Codex labels and calibrated to design-weighted sample rates; fields without enough sample support carry no Codex call. Candidate is the union of the two sides; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels.
metaresearch head score (Codex)0.000
metaresearch head score (Gemma)0.000
Version: metacan-v3-hybrid-931329e0061cValidation status: machine_predicted_unvalidated
Candidate categoriesnone
Consensus categoriesnone
DomainCandidate signal: none · Consensus signal: none
Study designCandidate signal: Observational · Consensus signal: Observational
GenreCandidate signal: Empirical · Consensus signal: Empirical
Teacher disagreement score0.005
Threshold uncertainty score0.018
Distilled classifier scores by category (both heads)
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.000 | 0.000 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.001 | 0.001 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.005 | 0.001 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
Opus teacher head0.015
GPT teacher head0.252
Teacher spread0.237 · how far apart the two teachers sit on this one work
Validation status
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one source (direct Gemma or distilled Codex), not a consensus.
The models applied no category: nothing in the taxonomy fit this work.
Study designObservational
Domainnot available
GenreEmpirical
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".
Quick stats
Citations2
Published2025
Admission routes1
Has abstractyes