Confirming the high velocity outflow in PG1211+143

An XMM-Newton observation of the bright quasi-stellar object PG1211+143 was previously reported to show evidence for a massive, energetic outflow, with an outflow velocity of v ~ 0.1c based on the identification of blueshifted absorption lines detected in both EPIC and Reflection Grating Spectrometer (RGS) spectra. Subsequently, an order of magnitude lower velocity has been claimed from an ion-by-ion model fit to the RGS data. We show here, in a re-analysis of the higher signal-to-noise ratio EPIC data, that the high velocity is confirmed, with the resolution of additional absorption lines yielding a revised outflow velocity in the range ~0.13-0.15c. Confirmation of a massive and energetic outflow in a non-BAL active galactic nucleus (AGN) has important implications for metal enrichment of the intergalactic medium and for the feedback mechanism implied by the correlation of black hole and galactic bulge masses. We note the near-Eddington luminosity of PG1211+143 may be the critical factor in driving such an energetic outflow, a situation likely to be common in AGN at higher redshift.