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arXiv · 2201.03218

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

Kwan-Lok Li
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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.

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Kwan-Lok Li. 2022-01-10. Evidence for Gamma-Ray Pulsations from the Classical Nova ASASSN-16ma. https://doi.org/10.3847/2041-8213%2Fac447d

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