Evidence for Gamma-Ray Pulsations from the Classical Nova ASASSN-16ma

Abstract

We report here a new result extracted from the Fermi Large Area Telescope observation of the classical nova ASASSN-16ma that exhibits coherent gamma-ray pulsations at 544.84(7) seconds during its outburst in 2016. Considering the number of independent trials, the significance of the evidence is 4.0 sigma, equivalent to a false alarm probability of 5.9e-5. The periodicity was steady during the 4 days of its appearance, indicating its origin as the spinning signal of the white dwarf. Given that the optical and gamma-ray light curves of some shock-powered gamma-ray novae have been recently shown closely correlated to each other, the gamma-ray pulsation phenomenon likely implies an existence of the associated optical pulsations, which would provide detailed ephemerides for these extreme white dwarf binaries for further investigations in the near future.

arXiv comment7 pages, including 4 figures. Accepted for publication in ApJL

References in corpus (18)

• The Man Behind the Curtain: X-rays Drive the UV through NIR Variability in the 2013 AGN Outburst in NGC 2617
• Fermi Large Area Telescope Fourth Source Catalog
• TEMPO2, a new pulsar timing package. I: Overview
• Gamma-Ray Emission Concurrent with the Nova in the Symbiotic Binary V407 Cygni
• A radio pulsing white dwarf binary star
• Fermi Establishes Classical Novae as a Distinct Class of Gamma-Ray Sources
• The spin periods and magnetic moments of white dwarfs in magnetic cataclysmic variables
• Cool and Luminous Transients from Mass-Losing Binary Stars
• Improving Sensitivity to Weak Pulsations with Photon Probability Weighting
• An Expanding Shell and Synchrotron Jet in RS Ophiuchi
• A Nova Outburst Powered by Shocks
• Novae as Tevatrons: Prospects for CTA and IceCube
• The expanding dusty bipolar nebula around the nova V1280 Sco
• Extending the Event-weighted Pulsation Search to Very Faint Gamma-ray Sources
• The Remarkable Spin-down and Ultra-fast Outflows of the Highly-Pulsed Supersoft Source of Nova Hercules 2021
• Search for gamma-ray emission from AE Aquarii with seven years of FERMI-LAT observations
• Modelling the broadband emission from the white dwarf binary system AR Scorpii
• An X-ray study for white dwarf binary AR Scorpii

Cited by in corpus (4)

• The multi-wavelength view of shocks in the fastest nova V1674 Her
• Investigation of a likely orbital periodicity of Nova Hercules 2021 in X-rays and gamma-rays
• Persistent nuclear burning in Nova Sgr 2016 N.4 (= V5856 Sgr = ASASSN-16ma) six years past its outburst
• Multi-wavelength study for gamma-ray nova V1405 Cas