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The High-Velocity Outflow of PG 1211+143: An Unbiased View Based on Several Observations

Shai Kaspi·Ehud Behar
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Abstract

We present and discuss high-resolution grating spectra of the quasar PG1211+143 obtained over three years. Based on an early observation from 2001, we find an outflow component of about 3000 km/s in contrast with the much higher velocity of about 24000 km/s reported earlier for this source, and based on the same data set. Subsequent grating spectra obtained for PG1211+143 are consistent with the first observation in the broad-band sense, but not all narrow features used to identify the outflow are reproduced. We demonstrate that the poor S/N and time variability seen during all existing observations of PG1211+143 make any claims about the outflow precariously inconclusive.

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Shai Kaspi, Ehud Behar. 2005-11-15. The High-Velocity Outflow of PG 1211+143: An Unbiased View Based on Several Observations. https://arxiv.org/abs/astro-ph/0511199

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