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Title: γ-Ray Emission from Classical Nova V392 Per: Measurements from Fermi and HAWC
Abstract

This paper reports on theγ-ray properties of the 2018 Galactic nova V392 Per, spanning photon energies ∼0.1 GeV–100 TeV by combining observations from the Fermi Gamma-ray Space Telescope and the HAWC Observatory. As one of the most rapidly evolvingγ-ray signals yet observed for a nova, GeVγ-rays with a power-law spectrum with an index Γ = 2.0 ± 0.1 were detected over 8 days following V392 Per’s optical maximum. HAWC observations constrain the TeVγ-ray signal during this time and also before and after. We observe no statistically significant evidence of TeVγ-ray emission from V392 Per, but present flux limits. Tests disfavor the extension of the Fermi Large Area Telescope spectrum to energies above 5 TeV by 2 standard deviations (95%) or more. We fit V392 Per’s GeVγ-rays with hadronic acceleration models, incorporating optical observations, and compare the calculations with HAWC limits.

Authors:
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Award ID(s):
1913011
Publication Date:
NSF-PAR ID:
10382678
Journal Name:
The Astrophysical Journal
Volume:
940
Issue:
2
Page Range or eLocation-ID:
Article No. 141
ISSN:
0004-637X
Publisher:
DOI PREFIX: 10.3847
Sponsoring Org:
National Science Foundation
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