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The High-Velocity Outflow of PG1211+143 May Not be That Fast

Shai Kaspi·Ehud Behar
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Abstract

We analyze the X-ray spectrum of the quasar PG1211+143 observed with the CCD and grating spectrometers on board XMM-Newton. Using an ion by ion fitting model we find an outflow component of about 3000 km/s that includes absorption lines of K-shell and L-shell ions of the astrophysically abundant elements. We also identify and include in our model broad (FWHM = 6000 km/s) emission lines from H-like ions of C, N, O, and Ne, and He-like ions of O, Ne, and Mg. The outflow velocity we find is an alternative interpretation of the data and is in contrast with the ultra high velocity of ~24000 km/s reported previously for this object. Nevertheless, we can not completely rule out the presence of a high velocity component due to the poor signal-to-noise ratio of the data.

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Shai Kaspi, Ehud Behar. 2005-09-19. The High-Velocity Outflow of PG1211+143 May Not be That Fast. https://doi.org/10.1086/498126

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