C.D.S. - SIMBAD4 rel 1.7 - 2020.11.24CET10:32:55

2001A&A...376..413O - Astronomy and Astrophysics, volume 376, 413-421 (2001/9-3)

BeppoSAX spectroscopy of MR 2251-178: A test for ionized reflection in radio quiet QSOs.


Abstract (from CDS):

We present the 0.1-200 keV BeppoSAX spectrum of MR 2251-178 observed at two epochs in 1998 separated by 5 months. Both epochs show identical spectral shape and X-ray flux. Analysis of the combined spectra allow us to confirm the presence of the ionized Fe Kα line detected by ASCA and to test the presence of reflection from ionized material. The best self-consistent spectral fit is obtained when including a contribution from a mildly ionized reflector (ξ0.01–100∼1625erg/cm/s, i.e. U0.1–10∼0.14) with a reflection fraction Rion∼0.11. An exponential cut-off to the direct power-law continuum is then required at E∼100keV. The low energy spectrum is absorbed by ionized matter with a column density NW=(8.1–1.2+2.1)x1021cm–2 and an X-ray ionization parameter U0.1–10=0.06±0.01. The warm absorber column is slightly lower than that measured with ASCA. This change could be caused by bulk motion. The BeppoSAX absorber ionization parameter globally agrees with the ``U versus Flux'' correlation found for MR 2251-178 with EXOSAT, Ginga and ASCA. This suggests that the absorber is in a state of instantaneous ionization equilibrium.

Abstract Copyright:

Journal keyword(s): galaxies: active - galaxies: quasars: individual - X-rays: galaxies

Simbad objects: 3

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Number of rows : 3

N Identifier Otype ICRS (J2000)
ICRS (J2000)
Mag U Mag B Mag V Mag R Mag I Sp type #ref
1850 - 2021
1 NGC 4151 Sy1 12 10 32.5771747733 +39 24 21.057727323   12.18 11.48     ~ 3408 2
2 NGC 5548 Sy1 14 17 59.5401093128 +25 08 12.600227883   14.35 13.73     ~ 2423 0
3 NAME MR 2251-178 Sy1 22 54 05.8858021308 -17 34 55.403006841   14.99 14.36 15.12   ~ 379 3

    Equat.    Gal    SGal    Ecl

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