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

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.

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Award ID(s):
1913011 2110809 2209103 1912708 1806408 1751874 1914549 2209533 2209419
Author(s) / Creator(s):
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DOI PREFIX: 10.3847
Date Published:
Journal Name:
The Astrophysical Journal
Medium: X Size: Article No. 141
["Article No. 141"]
Sponsoring Org:
National Science Foundation
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