Monitoring RXTE Observations of Markarian 348: the origin of the column density variations

Abstract

We analyze 37 RXTE observations of the type 2 Seyfert galaxy Mrk348 obtained during a period of 14 months. We confirm the spectral variability previous reported by Smith et al., in the sense that thecolumn density decreases by a factor of ~3 as the count rate increases. Column density variations could possibly originate either due to the random drift of clouds within the absorption screen, or due to photoionization processes. Our modeling of the observed variations implies that the first scenario is more likely. These clouds should lie in a distance of >2 light years from the source, having a diameter of a few light days and a density of >10^7 cm^(-3), hence probably residing outside the Broad Line Region.

6 pages, 3 figures, to appear in MNRAS

References in corpus (2)

• Ubiquitous variability of X-ray absorbing column densities in Seyfert 2 Galaxies
• Variable X-ray Absorption in the Seyfert 2 Galaxy Mrk 348

Cited by in corpus (9)

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• Discovery of Water Maser Emission in Five AGN and a Possible Correlation Between Water Maser and Nuclear 2-10 keV Luminosities
• X-ray spectral variability of Seyfert 2 galaxies
• Discovery of Newly Formed Broad Absorption Lines in a Radio-Loud Quasar
• A Variable-Density Absorption Event in NGC 3227 mapped with Suzaku and Swift
• On the fraction of X-ray obscured quasars in the local universe
• The variable ionized absorber in the Seyfert 2 Mrk 348