@article {604673,
	title = {The Ultra-fast Outflow of the Quasar PG 1211+143 as Viewed by Time-averaged Chandra Grating Spectroscopy},
	journal = {The Astrophysical Journal},
	volume = {853},
	year = {2018},
	pages = {165},
	abstract = {We present a detailed X-ray spectral study of the quasar PG 1211+143 based on Chandra High Energy Transmission Grating Spectrometer (HETGS) observations collected in a multi-wavelength campaign with UV data using the Hubble Space Telescope Cosmic Origins Spectrograph (HST-COS) and radio bands using the Jansky Very Large Array (VLA). We constructed a multi-wavelength ionizing spectral energy distribution using these observations and archival infrared data to create XSTAR photoionization models specific to the PG 1211+143 flux behavior during the epoch of our observations. Our analysis of the Chandra-HETGS spectra yields complex absorption lines from H-like and He-like ions of Ne, Mg, and Si, which confirm the presence of an ultra-fast outflow (UFO) with a velocity of approximately -17,300 km s-1\&nbsp;(outflow redshift zout\&nbsp;\~{} -0.0561) in the rest frame of PG 1211+143. This absorber is well described by an ionization parameter {log}ξ \~{} 2.9 {erg} {{{s}}}-1\&nbsp;{cm} and column density {log}{N}{{H}}\~{} 21.5 {{cm}}-2. This corresponds to a stable region of the absorber{\textquoteright}s thermal stability curve, and furthermore its implied neutral hydrogen column is broadly consistent with a broad Lyα absorption line at a mean outflow velocity of approximately -16,980 km s-1\&nbsp;detected by our HST-COS observations. Our findings represent the first simultaneous detection of a UFO in both X-ray and UV observations. Our VLA observations provide evidence for an active jet in PG 1211+143, which may be connected to the X-ray and UV outflows; this possibility can be evaluated using very-long-baseline interferometric observations.},
	url = {http://iopscience.iop.org/article/10.3847/1538-4357/aaa427/pdf},
	author = {Danehkar, Ashkbiz and Nowak, Michael A and Lee, Julia C. and Kriss, Gerard A and Young, Andrew J. and Hardcastle, Martin J. and Chakravorty, Susmita and Fang, Taotao and Neilsen, Joseph and Rahoui, Farid and Smith, Randall K.}
}
