Characterization of downward TGFs detected at the Pierre Auger Observatory
Downward Terrestrial Gamma-ray Flashes (TGFs) are sub-millisecond bursts of MeV gamma rays produced in thunderclouds. According to the Relativistic Runaway Electron Avalanche model, gamma rays are produced, via bremsstrahlung, from electron cascades activated by a relativistic “seed” electron. It is not clear what mechanism is responsible for the acceleration of electrons to relativistic energies in electric discharges. To better understand the acceleration sites and the TGF production mechanisms, it is critically important to identify the TGF source position and geometry in the atmosphere and to study the gamma emission characteristics. The Surface Detector of the Pierre Auger Observatory, with its 1600 water-Cherenkov detectors very sensitive to high-energy photons and with a very fine time-sampling, is a valuable instrument to study downward TGFs. The possibility to analyze the radiation emission in detail led to the observation of the first TGFs with an asymmetric azimuthal structure, suggesting a complex source different from the initially hypothesized downward beam. We report on these observations and the new perspectives which may open with the incorporation of new instruments at the Auger site to study lightning development alongside gamma emission, and the increasingly detailed data provided by satellites and global lightning networks.
Authors
- Belén Andrada
- Pedro J. Costa (ORCID: https://orcid.org/0000-0002-7476-7875)
- Zbigniew Szadkowski (ORCID: https://orcid.org/0000-0002-2690-9912)
- Bruno L. Lago (ORCID: https://orcid.org/0000-0001-9672-0499)
- Marvin Gottowik (ORCID: https://orcid.org/0000-0001-7436-389X)
- 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)
- Varada Varma Kizakke Covilakam (ORCID: https://orcid.org/0000-0001-5278-3172)
- T. Pierog (ORCID: https://orcid.org/0000-0002-7472-8710)
- G. Sigl (ORCID: https://orcid.org/0000-0002-4396-645X)
- Mateo Fernandez
- R. Engel (ORCID: https://orcid.org/0000-0003-2924-8889)
- 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)
- A. Bueno (ORCID: https://orcid.org/0000-0002-7439-4247)
- 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)
- Lorenzo Cazon (ORCID: https://orcid.org/0000-0001-6748-8395)
- Lukáš Vaclavek (ORCID: https://orcid.org/0000-0002-0910-3415)
- B. R. Dawson (ORCID: https://orcid.org/0000-0002-4271-3055)
- G. Salina (ORCID: https://orcid.org/0000-0003-1767-0724)
- 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)
- Laura Valore (ORCID: https://orcid.org/0000-0003-2682-8378)
- Janning Meinert (ORCID: https://orcid.org/0000-0001-7582-3456)
- Emanuele De Vito (ORCID: https://orcid.org/0000-0003-2045-7588)
- Dušan Mandát (ORCID: https://orcid.org/0000-0001-7748-7468)
- 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)
- V. Rizi (ORCID: https://orcid.org/0000-0002-5277-6527)
- Armando di Matteo (ORCID: https://orcid.org/0000-0002-8260-1867)
- David Smith (ORCID: https://orcid.org/0000-0002-5589-7201)
- 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)
- Srijan Sehgal
- Lorenzo Caccianiga (ORCID: https://orcid.org/0000-0002-2245-5108)
- 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)
- Alexandra Ramos Fernandes (ORCID: https://orcid.org/0000-0003-2054-4438)
- Viviana Scherini (ORCID: https://orcid.org/0000-0003-3762-4063)
- 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)
- Juan Carlos D’Olivo
- F. Salamida (ORCID: https://orcid.org/0000-0002-9306-8447)
- S. Stanič (ORCID: https://orcid.org/0000-0003-3344-8381)
- 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)
- Maximilian Straub
- R. Mussa (ORCID: https://orcid.org/0000-0002-0294-9071)
- Camilla Petrucci
- Steffen Hahn (ORCID: https://orcid.org/0000-0001-5040-3666)
- Federico Maria Mariani
- Fiona H. Ellwanger
- J. Vícha (ORCID: https://orcid.org/0000-0002-7945-3605)
- Jaime Álvarez-Muñiz (ORCID: https://orcid.org/0000-0002-2367-0803)
- C. Hojvat (ORCID: https://orcid.org/0000-0003-3323-3129)
- Олена Ткаченко (ORCID: https://orcid.org/0000-0002-6382-6390)
- 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)
- Glennys R. Farrar (ORCID: https://orcid.org/0000-0003-2417-5975)
- M. Erdmann (ORCID: https://orcid.org/0000-0002-1653-1303)
- Jarosław Stasielak (ORCID: https://orcid.org/0000-0002-9284-7000)
- H. Falcke (ORCID: https://orcid.org/0000-0002-2526-6724)
- Shima Ujjani Shivashankara
- C. E. Covault (ORCID: https://orcid.org/0000-0001-5405-5371)
- Alex Tapia (ORCID: https://orcid.org/0000-0003-0585-7161)
- 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)
- Antoine Letessier-Selvon
- 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)
- 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)
- J. R. Dwyer (ORCID: https://orcid.org/0000-0002-3581-1503)
- Rukije Uzeiroska
- Nicolás Martín González (ORCID: https://orcid.org/0000-0001-6566-2222)
- Silvia Mollerach (ORCID: https://orcid.org/0000-0002-9339-5317)
- 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)
- M. Pech (ORCID: https://orcid.org/0000-0002-8421-0456)
- 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)
- Luis A. Anchordoqui (ORCID: https://orcid.org/0000-0003-1463-7136)
- Jorge Caraça-Valente
- Krzysztof Pytel (ORCID: https://orcid.org/0000-0002-2937-7886)
- 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)
- Peter Mazur
- Jan Pękala (ORCID: https://orcid.org/0000-0002-1062-5595)
- Edyvânia Emily Pereira Martins (ORCID: https://orcid.org/0000-0002-1167-8314)
- Fridtjof Feldbusch
- Josina Schulte (ORCID: https://orcid.org/0000-0002-5822-2445)
- S. Vorobiov (ORCID: https://orcid.org/0000-0001-8679-3424)
- Alexander Novikov (ORCID: https://orcid.org/0000-0002-1086-7252)
- Emanuele Avocone (ORCID: https://orcid.org/0000-0003-3757-2718)
- 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)
- Italo Epicoco (ORCID: https://orcid.org/0000-0002-6408-1335)
- Leo Östman
- Fabio Convenga (ORCID: https://orcid.org/0000-0002-2841-1034)
- B. Tomé (ORCID: https://orcid.org/0000-0002-7564-8392)
- 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)
- Eva Santos (ORCID: https://orcid.org/0000-0002-0474-8863)
- Joaquín de Jesús (ORCID: https://orcid.org/0000-0002-4741-1769)
- Milton Freitas
- M. Pimenta (ORCID: https://orcid.org/0000-0002-2590-0908)
- 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)
- John Ortberg
- 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)
- R. W. Clay (ORCID: https://orcid.org/0000-0002-9040-9648)
- Katharine Mulrey (ORCID: https://orcid.org/0000-0001-8026-8020)
- Mario Buscemi (ORCID: https://orcid.org/0000-0003-2123-5434)
- Wilson M. Namasaka
- Vincent Pelgrims (ORCID: https://orcid.org/0000-0002-5053-3847)
- 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)
- Nikolas Denner
- Shayoni Panja
- Sergio Cabana-Freire (ORCID: https://orcid.org/0000-0002-4042-3855)
- Simon Strähnz
- 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)
- J.R. Hörandel (ORCID: https://orcid.org/0000-0001-6604-547X)
- M. Unger (ORCID: https://orcid.org/0000-0002-7651-0272)
- J. Chudoba (ORCID: https://orcid.org/0000-0002-6425-2579)
- Paolo Privitera (ORCID: https://orcid.org/0000-0002-0623-9261)
- Markus Roth (ORCID: https://orcid.org/0000-0002-9041-1414)
- A. De Roeck (ORCID: https://orcid.org/0000-0002-3234-6634)
- Jacco Vink (ORCID: https://orcid.org/0000-0002-0816-9949)
- Gioacchino Alex Anastasi (ORCID: https://orcid.org/0000-0003-0824-5283)
- José Ochoa (ORCID: https://orcid.org/0009-0001-1395-4159)
- Teresa Bister (ORCID: https://orcid.org/0000-0003-4005-0857)
- 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)
- Juan Pallotta (ORCID: https://orcid.org/0000-0003-4846-8748)
- Igor Vaiman (ORCID: https://orcid.org/0000-0002-8255-3631)
- David Schmidt (ORCID: https://orcid.org/0000-0001-6963-1191)
- Giorgio Matthiae
- Andrej Filipčič
- Humberto Ibarguen Salazar
- Rita Cassia dos Anjos
- Germano Guedes
- Analisa Mariazzi
- Norbert Kunka
- Luca Deval
- Stanislav Michal
- Johannes Blümer
- Jelena Köhler
- Antonino Del Popolo
- Danilo Zavrtanik (ORCID: https://orcid.org/0000-0002-4596-1521)
- Julian Rautenberg
- Fernando Gollan
- Luis Miguel Domingues Mendes
- Jaime de Oliveira
- Edivaldo Moura Santos
- Isabelle Lhenry-Yvon
- Qader Dorosti (ORCID: https://orcid.org/0000-0001-9711-0609)
- Alberto Etchegoyen
- Sara Martinelli
- Felix Riehn
- Charles Timmermans
- Paul Filip
- Marco Aglietta
- Carlos J. Todero Peixoto (ORCID: https://orcid.org/0000-0003-3669-8212)
- Alejandro Almela
- Gabriela Nicora
- Toshihiro Fujii
- Luan Bonneau Arbeletche (ORCID: https://orcid.org/0000-0002-3087-3609)
- Federico Andrés Sánchez
- Thomas Fitoussi
- Mariano Gómez Berisso
- Margita Kubátová
- Melanie Weitz (ORCID: https://orcid.org/0009-0001-9010-9610)
- A. A. Watson
- Primo F. Gómez Vitale
- Rogerio M. de Almeida
- Martina Boháčová
- Niklas Langner
- 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)
- Cristina Galea
- Kévin Almeida Cheminant (ORCID: https://orcid.org/0000-0001-6352-5339)
- Martin Schimassek (ORCID: https://orcid.org/0000-0003-4295-7719)
- Jose F. Valdés Galicia
- H. Schieler (ORCID: https://orcid.org/0000-0002-2637-4778)
- Andreas Weindl
- Sergio J Sciutto (ORCID: https://orcid.org/0000-0003-1148-3231)
- Petr Tobiska (ORCID: https://orcid.org/0000-0003-4017-2475)
- Lawrence Wiencke
- Jorge Rubén Rodriguez Rojo
- Markus Risse (ORCID: https://orcid.org/0000-0001-9660-8683)
- Daniele Martello
- Florian Lukas Briechle
- Marcelo Augusto Leigui de Oliveira
- Michael Prouza
- Marcos Cerda
- Michael Schimp
- Brian Wundheiler
- Piera Luisa Ghia
- P. Gabriel Brichetto Orchera
- Ruben Squartini
- Agustín Cobos Cerutti
- Manuel Platino
- Antonella Castellina
- Dave Nitz
- Brian Fick
- Alan Fuster
- Vladimír Novotný
- Lorenzo Perrone
- Petr Janeček (ORCID: https://orcid.org/0000-0003-3501-7163)
- Virginia Binet
- Diego Ravignani
- Rodrigo Pelayo (ORCID: https://orcid.org/0000-0002-1062-5595)
- Jeffrey Brack
- Marina Scornavacche
- Alexander Menshikov
- C. Dobrigkeit
- P. Abreu
- Juan Carlos Arteaga Velázquez
- Ioana Codrina Maris
- Indira D. Vergara Quispe
- Ricardo Sato
- Cainã Oliveira
- Max Büsken
- 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
- Diego Correia dos Santos
- Lorenzo Apollonio (ORCID: https://orcid.org/0009-0008-5625-5893)
- Carla Aramo
- Joao dos Anjos
- Roberto Aloisio
- Diego Melo
- Pierpaolo Savina
- Vlastimil Jílek (ORCID: https://orcid.org/0000-0001-5774-7285)
- Matías Rolf Hampel
- Veronika Vašíčková
- Paul Sommers
- Ugo GIACCARI
- Khoa Nguyen
- Luiz Augusto Pereira
- Adriana Vásquez-Ramírez
- Geraldina Golup
- Matteo Conte
- Ezequiel Rodríguez
- Jannis Pawlowsky
- Olivier Deligny
- Danelise de Oliveira Franco
- Juan Manuel Figueira
- Federico Campuzano
- Frederik Krieger
- Gael Flores Avila (ORCID: https://orcid.org/0000-0001-8375-6492)
- Sven Querchfeld
- Karl-Heinz Kampert
- Matthias Kleifges
- Sofia Andringa
- Gabriella Cataldi
- 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)
- Megha Mogarkar
- Jhansi Bhavani Vuta
- Eric-Teunis de Boone
- Mohamed Ismaiel
- Karolina Syrokvas
- Matteo Tambone
- Pim van Dillen
Publication Details
- Published
- 2025-09-23
- DOI
- https://doi.org/10.22323/1.501.0223
- Primary Topic
- Geophysics and Gravity Measurements
- Type
- article
- Field-Weighted Citation Impact
- 0.00
Funders
- Strong
- Consejo Nacional de Investigaciones Científicas y Técnicas
- Agencia Nacional de Promoción Científica y Tecnológica