  An XMM-Newton observation of the bright QSO 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 blue-shifted absorption lines
detected in both EPIC and 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 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 AGN has important
implications for metal enrichment of the IGM 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.
