Measurement of the cosmic-ray energy spectrum above 2.5 EeV using 19 years of operation of the Pierre Auger Observatory
We present the spectrum of cosmic rays with energies above 2.5 EeV measured at the Pierre Auger Observatory after 19 years of operation, covering the period before the AugerPrime upgrade. Two independent event sets from the surface array of 1500-m spaced detectors are combined, yielding a total exposure of 104 900 km² sr yr. The first set includes events with zenith angles less than 60°, while the second consists of events between 60° and 80°, for which azimuthal asymmetries must be accounted for in the energy estimator. The threshold energy is chosen to ensure a trigger efficiency of the surface detector greater than 97%, thus minimizing composition biases. The energy scale is determined using high-quality fluorescence measurements, providing calorimetric estimates without reliance on simulations. A statistically successful combination is achieved within the uncorrelated systematic uncertainties of the individual spectra. All spectra are consistent when analyzing potential declination dependences, except for a mild modulation expected from the previously reported dipolar anisotropy. In particular, this statement applies to the northernmost declination band [+24.8° ,+44.8°], where only events with zenith angles between 60° and 80° contribute. Beyond the firmly established ankle and suppression spectral features, the combined spectrum across declinations -90° to +45° provides a measurement of the instep feature with more than 5σ confidence.
Authors
- Belén Andrada
- Zbigniew Szadkowski (ORCID: https://orcid.org/0000-0002-2690-9912)
- Bruno L. Lago (ORCID: https://orcid.org/0000-0001-9672-0499)
- Carla Taricco (ORCID: https://orcid.org/0000-0002-0129-5539)
- Giovanni Consolati (ORCID: https://orcid.org/0000-0003-3614-245X)
- Juan Manuel Gonzalez (ORCID: https://orcid.org/0000-0001-9193-0921)
- S. Petrera (ORCID: https://orcid.org/0000-0002-6029-1255)
- T. Pierog (ORCID: https://orcid.org/0000-0002-7472-8710)
- G. Sigl (ORCID: https://orcid.org/0000-0002-4396-645X)
- Mateo Fernandez
- T. Huege (ORCID: https://orcid.org/0000-0002-2783-4772)
- Marta Bianciotto (ORCID: https://orcid.org/0000-0002-9599-3214)
- Nicolas Leal
- Carmina Pérez Bertolli (ORCID: https://orcid.org/0000-0002-9790-5732)
- Carlo Salvattore Cruz Sanchez (ORCID: https://orcid.org/0009-0002-6173-0974)
- Frank Schröder (ORCID: https://orcid.org/0000-0001-8495-7210)
- Gustavo Medina‐Tanco (ORCID: https://orcid.org/0000-0002-3202-319X)
- A. C. Fauth (ORCID: https://orcid.org/0000-0001-7239-0288)
- Enrico Arnone (ORCID: https://orcid.org/0000-0001-6740-5051)
- Enrique Varela (ORCID: https://orcid.org/0000-0003-0715-7513)
- O. Schölten (ORCID: https://orcid.org/0000-0003-3649-1254)
- Olena Tkachenko (ORCID: https://orcid.org/0000-0001-6393-7851)
- Lorenzo Cazon (ORCID: https://orcid.org/0000-0001-6748-8395)
- Pierpaolo Savina (ORCID: https://orcid.org/0000-0001-7670-554X)
- B. R. Dawson (ORCID: https://orcid.org/0000-0002-4271-3055)
- Laura Valore
- A. Haungs (ORCID: https://orcid.org/0000-0002-9638-7574)
- Harm Schoorlemmer (ORCID: https://orcid.org/0000-0002-8999-9249)
- Dalibor Nosek (ORCID: https://orcid.org/0000-0001-6219-200X)
- G. Parente (ORCID: https://orcid.org/0000-0003-2847-0461)
- Paula Gina Isar (ORCID: https://orcid.org/0000-0002-1241-584X)
- Janning Meinert (ORCID: https://orcid.org/0000-0001-7582-3456)
- Emanuele De Vito (ORCID: https://orcid.org/0000-0003-2045-7588)
- Adila Abdul Halim (ORCID: https://orcid.org/0000-0003-1218-1737)
- Gonzalo Rodriguez Fernandez (ORCID: https://orcid.org/0000-0002-4683-230X)
- Jiří Blažek (ORCID: https://orcid.org/0000-0002-5870-8947)
- Therese Paulsen
- Adriel Bartz Mocellin
- Berenika Čermáková
- S. J. de Jong (ORCID: https://orcid.org/0000-0002-3120-3367)
- Alexey Yushkov (ORCID: https://orcid.org/0000-0001-5107-9116)
- K. Daumiller (ORCID: https://orcid.org/0000-0002-0527-4823)
- A. Insolia (ORCID: https://orcid.org/0000-0002-9040-1566)
- Darko Veberič (ORCID: https://orcid.org/0000-0003-2683-1526)
- María Isabel Micheletti (ORCID: https://orcid.org/0000-0002-1063-9938)
- A. Segreto (ORCID: https://orcid.org/0000-0001-7341-6603)
- L. Nellen (ORCID: https://orcid.org/0000-0003-1059-8731)
- Felicia Barbato (ORCID: https://orcid.org/0000-0003-0751-6731)
- Jan Pękala
- Viviana Scherini (ORCID: https://orcid.org/0000-0003-3762-4063)
- Gabriela Nicora (ORCID: https://orcid.org/0000-0001-7504-6423)
- Thomas Fitoussi (ORCID: https://orcid.org/0000-0001-9473-9356)
- Katarína Simkova (ORCID: https://orcid.org/0000-0003-2363-9846)
- R. Caruso (ORCID: https://orcid.org/0000-0003-1622-8731)
- I. Allekotte (ORCID: https://orcid.org/0000-0002-9624-3044)
- F. Sarazin (ORCID: https://orcid.org/0000-0001-5614-1986)
- V. Verzi (ORCID: https://orcid.org/0000-0003-2291-9387)
- Luis A. Núñez
- Chaitanya Priyadarshi (ORCID: https://orcid.org/0000-0002-9160-9617)
- M. Cristinziani (ORCID: https://orcid.org/0000-0003-3893-9171)
- E. Zas (ORCID: https://orcid.org/0000-0002-4430-8117)
- Clara Keiko Oliveira Watanabe
- Roberta Colalillo (ORCID: https://orcid.org/0000-0002-4179-9352)
- M. Hrabovský (ORCID: https://orcid.org/0000-0003-4223-7316)
- L. Miramonti (ORCID: https://orcid.org/0000-0002-2808-5363)
- F. Simon (ORCID: https://orcid.org/0000-0002-5978-0289)
- F. Salamida (ORCID: https://orcid.org/0000-0002-9306-8447)
- P. Trávnı́ček (ORCID: https://orcid.org/0000-0002-1655-9584)
- Benjamin Flaggs (ORCID: https://orcid.org/0000-0002-5549-1869)
- P. Hamal (ORCID: https://orcid.org/0000-0003-3139-7234)
- A. D. Supanitsky (ORCID: https://orcid.org/0000-0002-6942-6216)
- Pedro J. Costa
- Maximilian Straub
- R. Mussa (ORCID: https://orcid.org/0000-0002-0294-9071)
- Camilla Petrucci
- Federico Maria Mariani
- Fiona H. Ellwanger
- A. Castellina (ORCID: https://orcid.org/0000-0002-0045-2467)
- J. Vícha (ORCID: https://orcid.org/0000-0002-7945-3605)
- Jaime Álvarez-Muñiz (ORCID: https://orcid.org/0000-0002-2367-0803)
- Jose F. Valdés Galicia
- Denise Boncioli (ORCID: https://orcid.org/0000-0003-1186-9353)
- L. Chytka (ORCID: https://orcid.org/0000-0001-5741-259X)
- Martin Vacula (ORCID: https://orcid.org/0000-0003-4844-3962)
- Miguel A. Martins (ORCID: https://orcid.org/0000-0002-7294-6204)
- F. Guarino (ORCID: https://orcid.org/0000-0003-1427-9885)
- M. Gómez Berisso (ORCID: https://orcid.org/0000-0001-5530-0180)
- M. Erdmann (ORCID: https://orcid.org/0000-0002-1653-1303)
- Jarosław Stasielak (ORCID: https://orcid.org/0000-0002-9284-7000)
- Shima Ujjani Shivashankara
- A. Letessier‐Selvon (ORCID: https://orcid.org/0000-0002-2044-3103)
- P. Abreu (ORCID: https://orcid.org/0000-0002-9973-7314)
- Tobias Schulz (ORCID: https://orcid.org/0000-0002-4208-2599)
- L. Nožka
- M. Palatka (ORCID: https://orcid.org/0000-0003-2061-6059)
- I. De Mitri (ORCID: https://orcid.org/0000-0002-8665-1730)
- K. S. Caballero‐Mora (ORCID: https://orcid.org/0000-0002-4042-3855)
- Antonio Franco (ORCID: https://orcid.org/0000-0001-7707-4241)
- Bjarni Pont (ORCID: https://orcid.org/0000-0002-2578-5364)
- Simone Rossoni
- S. Buitink (ORCID: https://orcid.org/0000-0002-6177-497X)
- Petr Tobiška (ORCID: https://orcid.org/0000-0002-0526-9098)
- Juan Ammerman Yebra (ORCID: https://orcid.org/0000-0002-2059-6206)
- Violet M. Harvey (ORCID: https://orcid.org/0000-0002-6764-4789)
- Achille Nucita (ORCID: https://orcid.org/0000-0002-7926-3481)
- Hermann-Josef Mathes (ORCID: https://orcid.org/0000-0002-0680-040X)
- P. Mantsch (ORCID: https://orcid.org/0000-0002-8382-7745)
- Lawrence Wiencke (ORCID: https://orcid.org/0000-0003-2878-9704)
- Rukije Uzeiroska
- Lorenzo Perrone (ORCID: https://orcid.org/0000-0002-8380-9643)
- Nicolás Martín González (ORCID: https://orcid.org/0000-0001-6566-2222)
- Silvia Mollerach (ORCID: https://orcid.org/0000-0002-9339-5317)
- Toshihiro Fujii (ORCID: https://orcid.org/0000-0003-2401-504X)
- Nicolas San Martin
- Corinne Bérat (ORCID: https://orcid.org/0000-0001-8294-6294)
- Zuzana Svozilikova (ORCID: https://orcid.org/0000-0001-5210-0781)
- М. Бертаина (ORCID: https://orcid.org/0000-0003-1069-1397)
- Maximilian Stadelmaier (ORCID: https://orcid.org/0000-0002-7943-6012)
- P. Assis (ORCID: https://orcid.org/0000-0001-7765-3606)
- F. Montanet (ORCID: https://orcid.org/0000-0001-9787-596X)
- Mohit Saharan
- T. Hebbeker (ORCID: https://orcid.org/0000-0002-9736-266X)
- M. Mallamaci (ORCID: https://orcid.org/0000-0003-4068-0496)
- Alena Bakalová (ORCID: https://orcid.org/0000-0003-1001-4484)
- Peter L. Biermann (ORCID: https://orcid.org/0000-0003-3948-6143)
- Jan Ebr (ORCID: https://orcid.org/0000-0001-8807-6162)
- Anthony Bwembya (ORCID: https://orcid.org/0000-0002-6995-5978)
- J. A. Chinellato (ORCID: https://orcid.org/0000-0002-1236-0789)
- Jorge Caraça-Valente
- Agustín Cobos Cerutti
- Krzysztof Pytel (ORCID: https://orcid.org/0000-0002-2937-7886)
- Adriana Vásquez-Ramírez (ORCID: https://orcid.org/0000-0001-7499-9302)
- R. Conceição (ORCID: https://orcid.org/0000-0003-4945-5340)
- C. Bonifazi (ORCID: https://orcid.org/0000-0002-3087-3609)
- Shefali Negi (ORCID: https://orcid.org/0000-0003-0891-0829)
- Jon Paul Lundquist (ORCID: https://orcid.org/0000-0002-4245-5092)
- Edyvânia Emily Pereira Martins (ORCID: https://orcid.org/0000-0002-1167-8314)
- Fridtjof Feldbusch
- S. Vorobiov (ORCID: https://orcid.org/0000-0001-8679-3424)
- Ezequiel Rodriguez (ORCID: https://orcid.org/0000-0002-2523-1919)
- Alexander Novikov (ORCID: https://orcid.org/0000-0002-1086-7252)
- Varada Varma Kizakke Covilakam
- Emanuele Avocone (ORCID: https://orcid.org/0000-0003-3757-2718)
- Primo F. Gómez Vitale (ORCID: https://orcid.org/0000-0001-9689-2020)
- H.O. Klages (ORCID: https://orcid.org/0000-0002-4306-021X)
- H. Wilczyński (ORCID: https://orcid.org/0000-0003-2652-9685)
- Antonio Ambrosone (ORCID: https://orcid.org/0000-0002-9942-1029)
- Pranav Sampathkumar
- Patricia María Hansen
- A. Gorgi (ORCID: https://orcid.org/0000-0002-8085-2304)
- F. de Palma (ORCID: https://orcid.org/0000-0001-5898-2834)
- V. de Souza (ORCID: https://orcid.org/0000-0003-0865-233X)
- Esteban Roulet (ORCID: https://orcid.org/0000-0003-1478-9260)
- S. Dasso (ORCID: https://orcid.org/0000-0002-7680-4721)
- Leo Östman
- Fabio Convenga (ORCID: https://orcid.org/0000-0002-2841-1034)
- J. Matthews (ORCID: https://orcid.org/0000-0002-1832-4420)
- Fernando Catalani (ORCID: https://orcid.org/0000-0001-9332-1476)
- Adrian Sedoski (ORCID: https://orcid.org/0000-0002-4253-3361)
- Radomir Šmída (ORCID: https://orcid.org/0000-0003-0122-1123)
- Joaquín de Jesús (ORCID: https://orcid.org/0000-0002-4741-1769)
- Milton Freitas
- Niklas Langner (ORCID: https://orcid.org/0000-0001-7443-3042)
- Carmelo Evoli (ORCID: https://orcid.org/0000-0002-6023-5253)
- Jose A. Bellido (ORCID: https://orcid.org/0000-0002-0833-9194)
- Kathrin Bismark (ORCID: https://orcid.org/0000-0001-8637-7041)
- Adrián Rovero (ORCID: https://orcid.org/0000-0001-6979-5604)
- D. Góra (ORCID: https://orcid.org/0000-0002-4853-5974)
- J. Řídký (ORCID: https://orcid.org/0000-0001-6697-1393)
- B. Keilhauer (ORCID: https://orcid.org/0000-0003-4494-1155)
- Stef Verpoest (ORCID: https://orcid.org/0000-0002-3031-3206)
- Katharine Mulrey (ORCID: https://orcid.org/0000-0001-8026-8020)
- Diego Correia dos Santos (ORCID: https://orcid.org/0000-0001-8243-6710)
- Mario Buscemi (ORCID: https://orcid.org/0000-0003-2123-5434)
- Wilson M. Namasaka
- Vincent Pelgrims (ORCID: https://orcid.org/0000-0002-5053-3847)
- Olivier Deligny (ORCID: https://orcid.org/0000-0001-6863-6572)
- Chloé Gaudu (ORCID: https://orcid.org/0000-0002-2803-4873)
- Yago Lema-Capeans
- Carmen Merx
- Mohsen Pourmohammad Shahvar
- Lukas Gülzow (ORCID: https://orcid.org/0009-0001-0620-3525)
- Simon Strähnz
- Shayoni Panja
- Sergio Cabana-Freire
- Nikolas Denner
- Beatriz de Errico (ORCID: https://orcid.org/0009-0002-4212-0708)
- João Vítor Reginatto Akim (ORCID: https://orcid.org/0000-0001-8179-9747)
- Fedor Tairli
- Alex Reuzki
- Tim Fehler
- Eric William Mayotte (ORCID: https://orcid.org/0000-0003-2618-9166)
- M. Unger (ORCID: https://orcid.org/0000-0002-7651-0272)
- J. Chudoba (ORCID: https://orcid.org/0000-0002-6425-2579)
- Markus Roth (ORCID: https://orcid.org/0000-0002-9041-1414)
- A. De Roeck (ORCID: https://orcid.org/0000-0002-3234-6634)
- Brian Wundheiler (ORCID: https://orcid.org/0000-0003-3121-7037)
- Gioacchino Alex Anastasi (ORCID: https://orcid.org/0000-0003-0824-5283)
- José Ochoa (ORCID: https://orcid.org/0009-0001-1395-4159)
- Tiina Suomijärvi (ORCID: https://orcid.org/0000-0003-1422-258X)
- Marko Zavrtanik (ORCID: https://orcid.org/0000-0001-5606-6912)
- Jose Sanabria Gomez (ORCID: https://orcid.org/0000-0002-4217-3212)
- B. Garćıa (ORCID: https://orcid.org/0000-0003-0919-2734)
- Marcus Niechciol (ORCID: https://orcid.org/0000-0001-6823-8056)
- Leonel Morejón (ORCID: https://orcid.org/0000-0003-1494-2624)
- J. Brack (ORCID: https://orcid.org/0000-0003-4096-2063)
- Igor Vaiman (ORCID: https://orcid.org/0000-0002-8255-3631)
- Juan Carlos D'Olivo
- Markus Risse
- Juan Pallotta
- Alejandro Almela
- Humberto Ibarguen Salazar
- Rita Cassia dos Anjos
- Jörg R. Hörandel
- Germano Guedes
- Analisa Mariazzi
- Sergio J Sciutto
- Luca Deval
- Peter Mazur
- Marvin Gottowik
- Stanislav Michal
- Johannes Blümer
- Jelena Köhler
- Antonino Del Popolo
- Danilo Zavrtanik (ORCID: https://orcid.org/0000-0002-4596-1521)
- Ralph Engel
- Julian Rautenberg
- Fernando Gollan
- Luis Miguel Domingues Mendes
- Edivaldo Moura Santos
- Lukáš Vaclavek
- Isabelle Lhenry-Yvon
- Carlos Hojvat
- Qader Dorosti (ORCID: https://orcid.org/0000-0001-9711-0609)
- Italo Epicoco
- Alberto Etchegoyen
- Bernardo Tomé
- Felix Riehn
- Charles Timmermans
- Paul Filip
- Antonio Bueno
- A. Filipčič (ORCID: https://orcid.org/0000-0001-5671-1555)
- Marco Aglietta
- Carlos J. Todero Peixoto (ORCID: https://orcid.org/0000-0003-3669-8212)
- Josina Schulte
- Eva Santos
- Luan Bonneau Arbeletche (ORCID: https://orcid.org/0000-0002-3087-3609)
- Federico Andrés Sánchez
- Roger W Clay
- Margita Kubátová
- Melanie Weitz (ORCID: https://orcid.org/0009-0001-9010-9610)
- A. A. Watson
- Rogerio M. de Almeida
- Glennys R. Farrar
- Martina Boháčová
- R. Sarmento (ORCID: https://orcid.org/0000-0002-5018-5467)
- Pavel Horváth (ORCID: https://orcid.org/0000-0002-6710-5339)
- G. Marsella (ORCID: https://orcid.org/0000-0002-3152-8874)
- Nataliia Borodai (ORCID: https://orcid.org/0000-0003-1864-937X)
- Kévin Almeida Cheminant (ORCID: https://orcid.org/0000-0001-6352-5339)
- Miroslav Pech
- Martin Schimassek (ORCID: https://orcid.org/0000-0003-4295-7719)
- H. Schieler (ORCID: https://orcid.org/0000-0002-2637-4778)
- Andreas Weindl
- Jorge Rubén Rodriguez Rojo
- Daniele Martello
- Florian Lukas Briechle
- Samo Stanič (ORCID: https://orcid.org/0000-0003-3344-8381)
- Marcelo Augusto Leigui de Oliveira
- Giorgio Matthiae
- Michael Prouza
- Marcos Cerda
- Vincenzo Rizi
- Michael Schimp
- Mário Pimenta
- Piera Luisa Ghia
- P. Gabriel Brichetto Orchera
- Gaetano Salina
- Ruben Squartini
- Manuel Platino
- Corbin Covault
- Dave Nitz
- Brian Fick
- Alan Fuster
- Vladimír Novotný
- Petr Janeček (ORCID: https://orcid.org/0000-0003-3501-7163)
- Virginia Binet
- Diego Ravignani
- Rodrigo Pelayo (ORCID: https://orcid.org/0000-0002-1062-5595)
- Marina Scornavacche
- Alexander Menshikov
- Dusan Mandat
- C. Dobrigkeit
- Armando di Matteo
- Juan Carlos Arteaga Velázquez
- Ioana Codrina Maris
- Indira D. Vergara Quispe
- Ricardo Sato
- Paul Sommers
- Cainã Oliveira
- Max Büsken
- Luis A. Anchordoqui (ORCID: https://orcid.org/0000-0003-1463-7136)
- Gualberto Avila
- Steffen Hahn
- A. Săftoiu (ORCID: https://orcid.org/0000-0002-7903-6510)
- L. Lopes (ORCID: https://orcid.org/0000-0001-8571-0033)
- Patrick Stassi (ORCID: https://orcid.org/0000-0001-5584-8410)
- Abha Khakurdikar (ORCID: https://orcid.org/0000-0002-4857-5255)
- Sonja Mayotte (ORCID: https://orcid.org/0000-0001-8957-8033)
- Fabian Gobbi
- Jonathan Biteau
- Baobiao Yue
- Paolo Privitera
- Lorenzo Apollonio (ORCID: https://orcid.org/0009-0008-5625-5893)
- Carla Aramo
- Teresa Bister
- Srijan Sehgal
- Joao dos Anjos
- David Schmidt
- Roberto Aloisio
- Diego Melo
- Vlastimil Jílek (ORCID: https://orcid.org/0000-0001-5774-7285)
- Matías Rolf Hampel
- Veronika Vašíčková
- Alexandra Fernandes (ORCID: https://orcid.org/0000-0002-9187-4007)
- Ugo GIACCARI
- Khoa Nguyen
- Norbert Kunka
- Luiz Augusto Pereira
- Sara Martinelli
- Heino Falcke
- Cristina Galea
- Geraldina Golup
- Matteo Conte
- Jaime de Oliveira
- Jannis Pawlowsky
- Danelise de Oliveira Franco
- Juan Manuel Figueira
- Federico Campuzano
- Frederik Krieger
- Sven Querchfeld
- Karl-Heinz Kampert
- Jacco Vink
- Matthias Kleifges
- Sofia Andringa
- Alex Tapia
- Luciana Andrade Dourado
- Petr Schovánek (ORCID: https://orcid.org/0000-0002-5344-7645)
- Tomáš Fodran (ORCID: https://orcid.org/0009-0000-9529-0853)
- Matias Jorge Tueros (ORCID: https://orcid.org/0000-0003-1570-1419)
- G. Cataldi (ORCID: https://orcid.org/0000-0001-8066-7718)
- Megha Mogarkar
- Jhansi Bhavani Vuta
- Eric-Teunis de Boone
- Mohamed Ismaiel
- Karolina Syrokvas
- Matteo Tambone
- Pim van Dillen
Publication Details
- Published
- 2025-09-24
- DOI
- https://doi.org/10.22323/1.501.0370
- Primary Topic
- Dark Matter and Cosmic Phenomena
- Type
- article
- Field-Weighted Citation Impact
- 0.00
Funders
- Strong
- Consejo Nacional de Investigaciones Científicas y Técnicas
- Agencia Nacional de Promoción Científica y Tecnológica