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arXiv · 0810.3077

X-Ray Spectroscopy of the Classical Nova V458 Vulpeculae with Suzaku

Masahiro Tsujimoto·Dai Takei·Jeremy J. Drake·Jan-Uwe Ness·Shunji Kitamoto
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Abstract

We conducted a target of opportunity X-ray observation of the classical nova V458 Vulpeculae 88 days after the explosion using the Suzaku satellite. With a 20 ks exposure, the X-ray Imaging Spectrometer detected X-ray emission significantly harder than typical super-soft source emission. The X-ray spectrum shows K lines from N, Ne, Mg, Si, and S, and L-series emission from Fe in highly ionized states. The spectrum can be described by a single temperature (0.64 keV) thin thermal plasma model in collisional equilibrium with a hydrogen-equivalent extinction column density of ~3e21/cm2, a flux of ~1e-12 erg/s/cm2, and a luminosity of ~6e34 erg/s in the 0.3-3.0 keV band at an assumed distance of 13 kpc. We found a hint of an enhancement of N and deficiencies of O and Fe relative to other metals. The observed X-ray properties can be interpreted as the emission arising from shocks of ejecta from an ONe-type nova.

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Masahiro Tsujimoto, Dai Takei, Jeremy J. Drake, Jan-Uwe Ness, Shunji Kitamoto. 2008-10-17. X-Ray Spectroscopy of the Classical Nova V458 Vulpeculae with Suzaku. https://doi.org/10.1093/pasj%2F61.sp1.s69

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