A burst from the direction of UZ Fornacis with XMM-Newton

Martin Still; Koji Mukai

doi:10.1086/338103

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arXiv · astro-ph/0109270

A burst from the direction of UZ Fornacis with XMM-Newton

Martin Still·Koji Mukai

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Abstract

The XMM-Newton pointing towards the magnetic cataclysmic variable UZ For finds the source to be a factor > 10^3 fainter than previous EXOSAT and ROSAT observations. The source was not detected for the majority of a 22 ksec exposure with the EPIC cameras, suggesting that the accretion rate either decreased, or stopped altogether. However a 1.1 ksec burst was detected from UZ For during the observation. Spectral fits favour optically thin, kT = 4.4 keV thermal emission. Detection of the burst by the on-board Optical Monitor indicates that this was most probably an accretion event. The 0.1-10 keV luminosity of 2.1 x 10^30 erg/s is typical for accretion shock emission from high state polars and would result from the potential energy release of ~ 10^16 g of gas. There is no significant soft excess due to reprocessing in the white dwarf atmosphere.

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Martin Still, Koji Mukai. 2001-09-17. A burst from the direction of UZ Fornacis with XMM-Newton. https://doi.org/10.1086/338103

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