Astronomy and Astrophysics – Astrophysics
Scientific paper
1999-11-10
Astronomy and Astrophysics
Astrophysics
11 pages, 8 figures included in the text. To be published in Astronomy and Astrophysics
Scientific paper
The LINER nucleus of the nearby spiral galaxy M81 was pointed by BeppoSAX, which caught it at the highest (2-10) keV flux level observed so far. The LECS, MECS and PDS data, extending over (0.1-100) keV, are used to investigate the physical similarities and differences between LINERs and AGNs. The continuum is well fitted by a power law of photon index \sim 1.84, modified by little absorption due to cold material. Superimposed on the continuum BeppoSAX detects a 6.7 keV emission line (confirming an ASCA result) and an absorption edge at 8.6 keV. Both spectral features are consistent with being produced by iron at the same high ionization level, and probably also with the same column density. So, we suggest that they originate from transmission through highly ionized thin material. Concerning the origin of the continuum emission, we do not observe signs of reflection from the optically thick material of an accretion disk, as usually found in Seyfert 1's (a 6.4 keV emission line and a broad bump peaking at 10-20 keV). The low bolometric luminosity of the nucleus of M81 is consistent with being produced by advection dominated accretion; in this case the X-ray emission should be dominated by Comptonization, rather than by bremsstrahlung, in order to reproduce the steep spectrum observed over the (0.1-100) keV band.
Bassani Loredana
Cappi Massimo
Malaguti Giuseppe
Palumbo Giorgio G. C.
Pellegrini Sara
No associations
LandOfFree
The low luminosity AGN in the LINER galaxy M81: BeppoSAX discovery of highly ionized gas 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 The low luminosity AGN in the LINER galaxy M81: BeppoSAX discovery of highly ionized gas, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and The low luminosity AGN in the LINER galaxy M81: BeppoSAX discovery of highly ionized gas will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-495811