Title

Discovery of Gamma Rays from the Quiescent Sun with HAWC

Authors

A Albert, Los Alamos National Laboratory
R Alfaro, Universidad Nacional Autónoma de México
C Alvarez, Universidad Autónoma de Chiapas
J C. Arteaga-Velázquez, Universidad Michoacana de San Nicolás de Hidalgo
D Avila Rojas, Universidad Nacional Autónoma de México
H A. Ayala Solares, Pennsylvania State University
R Babu, Michigan Technological University
E Belmont-Moreno, Universidad Nacional Autónoma de México
C Brisbois, University of Maryland
K S. Caballero-Mora, Universidad Autónoma de Chiapas
T Capistrán, Universidad Nacional Autónoma de México
A Carramiñana, Instituto Nacional de Astrof'isica
S Casanova, Instytut Fizyki Jadrowej im Henryka Niewodniczanskiego Polskiej Akademii Nauk
O Chaparro-Amaro, Instituto Polit'ecnico Nacional
U Cotti, Universidad Michoacana de San Nicolás de Hidalgo
J Cotzomi, Benemérita Universidad Autónoma de Puebla
S Coutiño de León, University of Wisconsin-Madison
E De la Fuente, Universidad de Guadalajara
R Diaz Hernandez, Instituto Nacional de Astrof'isica
B L. Dingus, Los Alamos National Laboratory
M A. DuVernois, University of Wisconsin-Madison
M Durocher, Los Alamos National Laboratory
J C. Díaz-Vélez, Centro Universitario de Ciencias Exactase Ingenierias
R W. Ellsworth, University of Maryland
K Engel, University of Maryland
C Espinoza, Universidad Nacional Autónoma de México
K L. Fan, University of Maryland
K Fang, University of Wisconsin-Madison
M Fernández Alonso, Pennsylvania State University
H Fleischhack, Catholic University of America
N Fraija, Universidad Nacional Autónoma de México

Document Type

Article

Publication Date

8-4-2023

Abstract

We report the first detection of a TeV γ -ray flux from the solar disk (6.3 σ), based on 6.1 years of data from the High Altitude Water Cherenkov (HAWC) observatory. The 0.5-2.6 TeV spectrum is well fit by a power law, dN / dE = A( E / 1  TeV) ^ { -γ }, with A = (1.6 ± 0.3) × 10^ { -12 }  TeV ^ { -1 } cm ^ { -2 } s ^ { -1 } and γ = 3.62 ± 0.14. The flux shows a strong indication of anticorrelation with solar activity. These results extend the bright, hard GeV emission from the disk observed with Fermi-LAT, seemingly due to hadronic Galactic cosmic rays showering on nuclei in the solar atmosphere. However, current theoretical models are unable to explain the details of how solar magnetic fields shape these interactions. HAWC's TeV detection thus deepens the mysteries of the solar-disk emission.

Publication Title

Physical review letters

COinS