  The detection of a high velocity (~ 0.3c) inflow of highly ionized matter
during an extended XMM-Newton observation of the luminous Seyfert galaxy PG
1211+143 in 2014 provided the first direct evidence of a short-lived accretion
event, and an explanation for the powerful winds (UFOs) now recognised as a
common property of many luminous Seyfert galaxies. Although the ultra-fast
inflow - observed at a redshift of 0.483 - was detected in only one of seven
spacecraft orbits, weaker (lower column) but more persistent absorption is seen
- at a redshift of 0.123 - in the high exposure, soft X-ray (RGS) spectra
summed over all 7 individual spacecraft orbits. Similar stacking of the higher
energy (pn camera) spectra reveals underlying absorption at a redshift of
0.148. Interpreted, conventionally, as a Doppler redshift, the RGS observation
indicates a line-of-sight inflow velocity v ~ 0.038c and (free-fall) radial
location at 1400 R_g, with the higher redshift and ionization in pn camera
spectra perhaps detecting that inflow closer to the black hole. A very
different explanation would be absorption in matter subject to the strong
gravity close to the SMBH, an interpretation supported by the launch of a new
UFO in the final spacecraft orbit.
