A Comprehensive Observational Analysis of V1324 Sco, the Most Gamma-Ray Luminous Classical Nova to Date

It has recently been discovered that some, if not all, classical novae emit GeV gamma-rays during outburst, but the mechanics of this gamma-ray emission are still not well understood. We present here a comprehensive, multi-wavelength dataset---from radio to X-rays---for the most gamma-ray luminous classical nova to-date, V1324 Sco. Using this dataset, we show that V1324 Sco is a canonical dusty Fe-II type nova, with a bulk ejecta velocity of $1150 \pm 40~\rm km~s^{-1}$ and an ejecta mass of $2.0 \pm 0.4 \times 10^{-5}~M_{\odot}$. However, despite it's seeming normalcy, there is also evidence for complex shock interactions, including the aforementioned gamma-rays and early time high-brightness temperature radio emission. To explain how a nova can be simultaneously ordinary and have the highest gamma-ray luminosity to date we present a simplified model of the ejecta in which the strength of gamma-ray emission is set by properties the fast ejecta component that collides with a slower component to produce shocks. We conclude by detailing how this model can be tested using future gamma-ray detected novae.

Comments: 22 pages, 12 figures

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Affiliations: 1Queen's University Belfast, 2Queen's University Belfast, 3Queen's University Belfast, 4Queen's University Belfast, 5Queen's University Belfast, 6Harvard-Smithsonian Center for Astrophysics, 7Ohio University, 8University of California, Santa Cruz, 9Las Cumbres Observatory Global Telescope, 10University of Hawaii at Manoa, 11University of Hawaii at Manoa, 12University of Hawaii at Manoa, 13University of Hawaii at Manoa

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