SIMBAD references

2004ApJ...607..788D - Astrophys. J., 607, 788-793 (2004/June-1)

Iron Kα emission from the low-luminosity active galaxies M81 and NGC 4579.

DEWANGAN G.C., GRIFFITHS R.E., DI MATTEO T. and SCHURCH N.J.

Abstract (from CDS):

We report on the XMM-Newton spectroscopy of the low-luminosity active galaxies (LLAGNs) M81 and NGC 4579, both of which have known black hole masses and well-sampled spectral energy distributions (SEDs). The iron Kα line profiles from both LLAGNs can be described in terms of two components: a narrow line at 6.4 keV, and a moderately broad line (FWHM∼2x104 km/s) arising from highly ionized, He-like or H-like species (E∼6.8keV). We interpret the broad lines arising from an accretion disk, the inner edge of which is restricted to large radii (rin∼100rg). However, the Eddington ratio, L/LEdd, of these sources is 3-4 orders of magnitude lower than that required to photoionize a cold disk to He-like iron. We suggest that the lines can be explained as collisionally ionized X-ray lines arising from the transition region between a hot (radiatively inefficient) flow in the inner regions and a cold disk outside r∼100rg. The accretion flow geometry probed by our XMM-Newton observations is consistent with the truncated disk models proposed to explain the SED of LLAGNs.

Abstract Copyright: ∼

Journal keyword(s): Accretion, Accretion Disks - Galaxies: Active - Galaxies: Individual: Messier Number: M81 - Galaxies: Individual: NGC Number: NGC 4579 - X-Rays: Galaxies

Simbad objects: 4

goto Full paper

goto View the references in ADS

To bookmark this query, right click on this link: simbad:2004ApJ...607..788D and select 'bookmark this link' or equivalent in the popup menu