HAWC Study on the Ultra-high-energy Gamma-Ray Emissions from the Pulsar Wind Nebula G32.64+0.53
Year: 2026
Type: article
Abstract: Multi-TeV gamma-ray emission around eHWC J1850+001 (a source from the first HAWC catalog of gamma-ray sources emitting above 56 TeV) is spatially coincident with the pulsar wind nebula (PWN) G32.64+0.53, powered by PSR J1849-0001. The absence of counterparts in radio, optical, and GeV energy ranges, contrasted with clear detections in X-rays and very-high-energy (VHE) gamma rays, is indicative of a nonthermal leptonic origin for the nebula. We apply a systematic analysis pipeline, including a sophisticated model for the Galactic diffuse emission, to 2860 days of data from the HAWC Observatory. Our detailed analysis confirms that the ultra-high-energy (UHE) emission originates from G32.64+0.53, and we measure its spectrum up to 270 TeV with significant emission well beyond 100 TeV. We fit the multiwavelength observations with a time-dependent leptonic model powered by the pulsar’s rotational energy, and the results establish the nebula as a leptonic PeV accelerator, capable of accelerating electrons to a maximum energy of E cut ≥ 2.9 PeV (95% one-sided lower bound). The model also constrains the nebular magnetic field to 4.28 μ G, supporting a leptonic PWN origin for the observed UHE emission.
Source: The Astrophysical Journal
Authors: R. Alfaro, C. Alvarez, E. Anita-Rangel, M. Araya, J.C. Arteaga-Velázquez, D. Avila Rojas, H.A. Ayala Solares, R. Babu, P. Bangale, E. Belmont-Moreno, A. Bernal, K.S. Caballero-Mora, T. Capistrán, A. Carramiñana, F. Carreón, S. Casanova, U. Cotti, J. Cotzomi, S. Coutiño de León, E. De la Fuente, P. Desiati, N. Di Lalla, R. Diaz Hernandez, M.A. DuVernois, J.C. Díaz-Vélez, K. Engel, T. Ergin, C. Espinoza, N. Fraija, S. Fraija, J.A. García-González, F. Garfias, N. Ghosh, M.M. González, J.A. González, J.A. Goodman, D. Guevel, J. Gyeong, J.P. Harding, I. Herzog, D. Huang, F. Hueyotl-Zahuantitla, P. Hüntemeyer, A. Iriarte, S. Kaufmann, D. Kieda, K. Leavitt, W.H. Lee, J. Lee, C. de León, H. León Vargas, A.L. Longinotti, G. Luis-Raya, K. Malone, O. Martinez, J. Martínez-Castro, J.A. Matthews, P. Miranda-Romagnoli, J.A. Morales-Soto, E. Moreno, M. Mostafá, M. Najafi, A. Nayerhoda, L. Nellen, R. Noriega-Papaqui, N. Omodei, E. Ponce, Y. Pérez Araujo, E.G. Pérez-Pérez, A. Pratts, S. Recchia, C.D. Rho, A. Rodriguez Parra, D. Rosa-González, M. Roth, H. Salazar, D. Salazar-Gallegos, A. Sandoval, M. Schneider, J. Serna-Franco, M. Shin, A.J. Smith, Y. Son, R.W. Springer, O. Tibolla, K. Tollefson, I. Torres, R. Torres-Escobedo, E. Varela, L. Villaseñor, X. Wang, Z. Wang, I.J. Watson, S. Yu, X. Zhang, H. Zhou
Institutions: Universidad Nacional Autónoma de México, Universidad Autónoma de Chiapas, Universidad de Costa Rica, Universidad Michoacana de San Nicolás de Hidalgo, Temple University, Michigan State University, University of Turin, Institute of Nuclear Physics, Polish Academy of Sciences, Benemérita Universidad Autónoma de Puebla, Universitat de València, Stanford University, University of Maryland, College Park, Tecnológico de Monterrey, Michigan Technological University, Sungkyunkwan University, Los Alamos National Laboratory, University of Delaware, Universidad Politécnica de Pachuca, University of Utah, University of Seoul, Instituto Politécnico Nacional, University of New Mexico, Universidad Autónoma del Estado de Hidalgo, Shanghai Jiao Tong University, Missouri University of Science and Technology, Pennsylvania State University
Language: English
Subfield: Nuclear and High Energy Physics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: gold
Estimated APC paid: $4,499
Funders: National Science Foundation, U.S. Department of Energy, National Aeronautics and Space Administration, European Commission, National Research Foundation, Consejo Nacional de Ciencia y Tecnología, National Research Foundation of Korea, Benemérita Universidad Autónoma de Puebla, Office of National Higher Education Science Research and Innovation Policy Council, Dirección General de Asuntos del Personal Académico, Universidad Nacional Autónoma de México, Coordinación de la Investigación Científica, Institute for Cosmic Ray Research, University of Tokyo, Laboratory Directed Research and Development, Los Alamos National Laboratory
Awards: G1012113107, G1137351982, G1451311200, G1477402476, G1943778919, G201248631, G20842220, G227081073, G2539654950, G2834597881, G3092080779, G3432588090, G3455266465, G3650325917, G4234058003, G4385750942, G4656072107, G4673649240, G4840023426, G5185440073, G5756405743, G5884581963, G5928845074, G5984383661, G6809838226, G6874468849, G6958583472, G7162220615, G7223072566, G726386190, G7379686924, G7757046036, G8432112341, G8651248068, G8700648374
OpenAlex ID: W7140074479