Astronomy and Astrophysics – Astrophysics
Scientific paper
2008-03-27
Astronomy and Astrophysics
Astrophysics
42 pages, 12 figures, Accepted in Apj. Typo in abstract (ver2): "We do not find evidence for an extra..."
Scientific paper
10.1086/587949
We present an analysis of our Chandra Low Energy Transmission Grating Spectrometer (LETGS) observation of the quasar MR2251-178. The warm absorber of MR2251-178 is well described by a hydrogen column density, N_H~2x10^21 cm^-2, and an ionization parameter log(xi)~0.6. We find in the spectrum weak evidence for narrow absorption lines from Carbon and Nitrogen which indicate that the ionized material is in outflow. We note changes (in time) of the absorption structure in the band (0.6-1) keV (around the UTAs plus the OVII and OVIII K-edges) at different periods of the observation. We measure a (0.1-2) keV flux of 2.58x10^-11 ergs cm^-2 s^-1. This flux implies that the nuclear source of MR2251-178 is in a relatively low state. No significant variability is seen in the light curve. We do not find evidence for an extra cold material in the line of sight, and set an upper limit of N_H~1.2x10^20 cm^-2. The X-ray spectrum does not appear to show evidence for dusty material, though an upper limit in the neutral carbon and oxygen column densities can only be set to N_CI~2x10^19 cm^-2 and N_OI~9x10^19 cm^-2, respectively.
Burwitz Vadim
Komossa Stefanie
Mathur Savita
Ramirez Jorge M.
No associations
LandOfFree
Chandra LETGS spectroscopy of the Quasar MR2251-178 and its warm absorber does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Chandra LETGS spectroscopy of the Quasar MR2251-178 and its warm absorber, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Chandra LETGS spectroscopy of the Quasar MR2251-178 and its warm absorber will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-354033