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arXiv · 1203.4804

XMM-Newton EPIC and OM observation of Nova Centauri 1986 (V842 Cen)

G. J. M. Luna·M. P. Diaz·N. S. Brickhouse·M. Moraes
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Abstract

We report the results from the temporal and spectral analysis of an XMM-Newton observation of Nova Centauri 1986 (V842 Cen). We detect a period at 3.51$\pm$0.4 h in the EPIC data and at 4.0$\pm$0.8 h in the OM data. The X-ray spectrum is consistent with the emission from an absorbed thin thermal plasma with a temperature distribution given by an isobaric cooling flow. The maximum temperature of the cooling flow model is $kT_{max}=43_{-12}^{+23}$ keV. Such a high temperature can be reached in a shocked region and, given the periodicity detected, most likely arises in a magnetically-channelled accretion flow characteristic of intermediate polars. The pulsed fraction of the 3.51 h modulation decreases with energy as observed in the X-ray light curves of magnetic CVs, possibly due either to occultation of the accretion column by the white dwarf body or phase-dependent to absorption. We do not find the 57 s white dwarf spin period, with a pulse amplitude of 4 mmag, reported by Woudt et al. (2009) either in the Optical Monitor (OM) data, which are sensitive to pulse amplitudes $\gtrsim$ 0.03 magnitudes, or the EPIC data, sensitive to pulse fractions $p \gtrsim$ 14 $\pm$2%.

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G. J. M. Luna, M. P. Diaz, N. S. Brickhouse, M. Moraes. 2012-03-21. XMM-Newton EPIC and OM observation of Nova Centauri 1986 (V842 Cen). https://doi.org/10.1111/j.1745-3933.2012.01260.x

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