2004A&A...414..107B


Query : 2004A&A...414..107B

2004A&A...414..107B - Astronomy and Astrophysics, volume 414, 107-116 (2004/1-4)

XMM-Newton observations of the two X-ray weak quasars PG 1411+442 and Mrk 304.

BRINKMANN W., PAPADAKIS I.E. and FERRERO E.

Abstract (from CDS):

We present the results of XMM-Newton observations of two X-ray weak quasars, PG 1411+442 and Mrk 304. In both cases the spectra can basically be represented by hard power laws with photon indices typical for radio-quiet quasars, heavily intrinsically absorbed by column densities of ∼2x1023cm–2 in PG 1411+442 and ∼4x1022cm–2 in Mrk 304. The data require in both cases an additional steep (Γ∼3) soft power law component, absorbed only by the galactic column density towards the quasars. The soft parts of the spectra exhibit additional complex structures like emission line features around ∼0.59keV, and absorption edges around 0.7keV and ∼1keV. These features strongly suggest the presence of ``warm" (i.e. ionized) material in the central region of the two sources. Due to the insufficient photon statistics and to the lack of more advanced models for the spectral fitting, we are unable to determine accurately the geometry and physical state of the absorbing material. The physical implications of various viable spectral absorption or scattering scenarios for the nature of these objects and of the X-ray weak quasars in general, are discussed.

Abstract Copyright:

Journal keyword(s): galaxies: active - quasars: general - quasars: individual: PG 1411+442, Mrk 304

Simbad objects: 3

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Number of rows : 3
N Identifier Otype ICRS (J2000)
RA
ICRS (J2000)
DEC
Mag U Mag B Mag V Mag R Mag I Sp type #ref
1850 - 2024
#notes
1 Ton 951 Sy1 08 47 42.4485615096 +34 45 04.482515304   14.83 14.50     ~ 466 0
2 LEDA 50824 Sy1 14 13 48.3306274368 +44 00 14.003371296   14.99 14.99     ~ 384 0
3 Mrk 304 Sy1 22 17 12.2637639888 +14 14 20.917852980   15.02 14.66     ~ 355 0

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