A lower bound on intergalactic magnetic fields from time variability of 1ES 0229+200 from MAGIC and Fermi/LAT observations
Abstract
Extended and delayed emission around distant TeV sources induced by the effects of propagation of gamma rays through the intergalactic medium can be used for the measurement of the intergalactic magnetic field (IGMF). We search for delayed GeV emission from the hard-spectrum TeV blazar 1ES 0229+200 with the goal to detect or constrain the IGMF-dependent secondary flux generated during the propagation of TeV gamma rays through the intergalactic medium. We analyze the most recent MAGIC observations over a 5 year time span and complement them with historic data of the H.E.S.S. and VERITAS telescopes along with a 12-year long exposure of the Fermi/LAT telescope. We use them to trace source evolution in the GeV-TeV band over one-and-a-half decade in time. We use Monte Carlo simulations to predict the delayed secondary gamma-ray flux, modulated by the source variability, as revealed by TeV-band observations. We then compare these predictions for various assumed IGMF strengths to all available measurements of the gamma-ray flux evolution. We find that the source flux in the energy range above 200 GeV experiences variations around its average on the 14 years time span of observations. No evidence for the flux variability is found in 1-100 GeV energy range accessible to Fermi/LAT. Non-detection of variability due to delayed emission from electromagnetic cascade developing in the intergalactic medium imposes a lower bound of B>1.8e-17 G for long correlation length IGMF and B>1e-14 G for an IGMF of the cosmological origin. Though weaker than the one previously derived from the analysis of Fermi/LAT data, this bound is more robust, being based on a conservative intrinsic source spectrum estimate and accounting for the details of source variability in the TeV energy band. We discuss implications of this bound for cosmological magnetic fields which might explain the baryon asymmetry of the Universe.
Keywords
Cite
@article{arxiv.2210.03321,
title = {A lower bound on intergalactic magnetic fields from time variability of 1ES 0229+200 from MAGIC and Fermi/LAT observations},
author = {MAGIC Collaboration and V. A. Acciari and I. Agudo and T. Aniello and S. Ansoldi and L. A. Antonelli and A. Arbet Engels and M. Artero and K. Asano and D. Baack and A. Babić and A. Baquero and U. Barres de Almeida and J. A. Barrio and I. Batković and J. Becerra González and W. Bednarek and E. Bernardini and M. Bernardos and A. Berti and J. Besenrieder and W. Bhattacharyya and C. Bigongiari and A. Biland and O. Blanch and H. Bökenkamp and G. Bonnoli and Ž. Bošnjak and I. Burelli and G. Busetto and R. Carosi and G. Ceribella and M. Cerruti and Y. Chai and A. Chilingarian and S. Cikota and E. Colombo and J. L. Contreras and J. Cortina and S. Covino and G. D'Amico and V. D'Elia and P. Da Vela and F. Dazzi and A. De Angelis and B. De Lotto and A. Del Popolo and M. Delfino and J. Delgado and C. Delgado Mendez and D. Depaoli and F. Di Pierro and L. Di Venere and E. Do Souto Espiñeira and D. Dominis Prester and A. Donini and D. Dorner and M. Doro and D. Elsaesser and V. Fallah Ramazani and L. Fariña and A. Fattorini and L. Font and C. Fruck and S. Fukami and Y. Fukazawa and R. J. García López and M. Garczarczyk and S. Gasparyan and M. Gaug and N. Giglietto and F. Giordano and P. Gliwny and N. Godinović and J. G. Green and D. Green and D. Hadasch and A. Hahn and T. Hassan and L. Heckmann and J. Herrera and D. Hrupec and M. Hütten and T. Inada and R. Iotov and K. Ishio and Y. Iwamura and I. Jiménez Martínez and J. Jormanainen and L. Jouvin and D. Kerszberg and Y. Kobayashi and H. Kubo and J. Kushida and A. Lamastra and D. Lelas and F. Leone and E. Lindfors and L. Linhoff and I. Liodakis and S. Lombardi and F. Longo and R. López-Coto and M. López-Moya and A. López-Oramas and S. Loporchio and A. Lorini and B. Machado de Oliveira Fraga and C. Maggio and P. Majumdar and M. Makariev and M. Mallamaci and G. Maneva and M. Manganaro and K. Mannheim and M. Mariotti and M. Martínez and A. Mas Aguilar and D. Mazin and S. Menchiari and S. Mender and S. Mićanović and D. Miceli and T. Miener and J. M. Miranda and R. Mirzoyan and E. Molina and H. A. Mondal and A. Moralejo and D. Morcuende and V. Moreno and E. Moretti and T. Nakamori and C. Nanci and L. Nava and V. Neustroev and M. Nievas Rosillo and C. Nigro and K. Nilsson and K. Nishijima and K. Noda and S. Nozaki and Y. Ohtani and T. Oka and J. Otero-Santos and S. Paiano and M. Palatiello and D. Paneque and R. Paoletti and J. M. Paredes and L. Pavletić and P. Peñil and M. Persic and M. Pihet and P. G. Prada Moroni and E. Prandini and C. Priyadarshi and I. Puljak and W. Rhode and M. Ribó and J. Rico and C. Righi and A. Rugliancich and N. Sahakyan and T. Saito and S. Sakurai and K. Satalecka and F. G. Saturni and B. Schleicher and K. Schmidt and F. Schmuckermaier and J. L. Schubert and T. Schweizer and J. Sitarek and I. Šnidarić and D. Sobczynska and A. Spolon and A. Stamerra and J. Strišković and D. Strom and M. Strzys and Y. Suda and T. Surić and M. Takahashi and R. Takeishi and F. Tavecchio and P. Temnikov and T. Terzić and M. Teshima and L. Tosti and S. Truzzi and A. Tutone and S. Ubach and J. van Scherpenberg and G. Vanzo and M. Vazquez Acosta and S. Ventura and V. Verguilov and I. Viale and C. F. Vigorito and V. Vitale and I. Vovk and M. Will and C. Wunderlich and T. Yamamoto and D. Zarić and A. Neronov and D. Semikoz and A. Korochkin},
journal= {arXiv preprint arXiv:2210.03321},
year = {2023}
}
Comments
10 pages, 5 figures, accepted to A&A. Corresponding authors: Ievgen Vovk, Paolo Da Vela (mailto:[email protected]) and Andrii Neronov (mailto:[email protected])