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arXiv · 1512.02587

X-ray timing analysis of the quasar PG 1211+143

Andrew Lobban·Simon Vaughan·Ken Pounds·James Reeves
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Abstract

We report on a timing analysis of a new ~630ks XMM-Newton observation of the quasar, PG 1211+143. We find a well-defined X-ray power spectrum with a well-detected bend at ~7e-5 Hz, consistent with the established bend-timescale--black-hole-mass correlation for luminous, accreting black holes. We find the linear rms-flux relation commonly observed in accreting black hole systems and investigate the energy-dependence of the rms. The fractional rms is roughly constant with energy on short timescales (< 1 day; within observations) whereas there is enhanced soft band variability on long timescales (between observations typically spaced by a few days). Additionally, we also report on the optical--UV variability using the OM on-board XMM-Newton and a ~2-month-long overlapping monitoring programme with Swift. We find that, although there is little UV variability within observations (<1 day), UV variations of a few per cent exist on time-scales of ~days--weeks.

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Andrew Lobban, Simon Vaughan, Ken Pounds, James Reeves. 2015-12-08. X-ray timing analysis of the quasar PG 1211+143. https://doi.org/10.1093/mnras%2Fstv2896

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