Cookies

We use cookies to ensure that we give you the best experience on our website. By continuing to browse this repository, you give consent for essential cookies to be used. You can read more about our Privacy and Cookie Policy.


Durham Research Online
You are in:

Gamma-ray novae: rare or nearby?

Morris, P.J. and Cotter, G. and Brown, A.M. and Chadwick, P.M. (2017) 'Gamma-ray novae: rare or nearby?', Monthly notices of the Royal Astronomical Society., 465 (1). pp. 1218-1226.

Abstract

Classical novae were revealed as a surprise source of γ-rays in Fermi Large Area Telescope (LAT) observations. During the first 8 yr since the LAT was launched, 6 novae in total have been detected to >5σ in γ-rays, in contrast to the 69 discovered optically in the same period. We attempt to resolve this discrepancy by assuming all novae are γ-ray emitters, and assigning peak 1 d fluxes based on a flat distribution of the known emitters to a simulated population. To determine optical parameters, the spatial distribution and magnitudes of bulge and disc novae in M31 are scaled to the Milky Way, which we approximate as a disc with a 20 kpc radius and elliptical bulge with semimajor axis 3 kpc and axis ratios 2:1 in the xy plane. We approximate Galactic reddening using a double exponential disc with vertical and radial scaleheights of rd = 5 kpc and zd = 0.2 kpc, and demonstrate that even such a rudimentary model can easily reproduce the observed fraction of γ-ray novae, implying that these apparently rare sources are in fact nearby and not intrinsically rare. We conclude that classical novae with mR ≤ 12 and within ≈ 8 kpc are likely to be discovered in γ-rays using the Fermi LAT.

Item Type:Article
Full text:(VoR) Version of Record
Download PDF
(1481Kb)
Status:Peer-reviewed
Publisher Web site:https://doi.org/10.1093/mnras/stw2776
Publisher statement:This article has been accepted for publication in Monthly Notices of the Royal Astronomical Society ©: 2016 The Authors. Published by Oxford University Press on behalf of the Royal Astronomical Society. All rights reserved.
Date accepted:20 February 2017
Date deposited:21 February 2017
Date of first online publication:27 October 2016
Date first made open access:21 February 2017

Save or Share this output

Export:
Export
Look up in GoogleScholar