Astronomy and Astrophysics – Astrophysics
Scientific paper
2001-05-09
Mon.Not.Roy.Astron.Soc. 328 (2001) 931
Astronomy and Astrophysics
Astrophysics
14 pages, 7 figures. Accepted for publication in MNRAS. Postscript file also available at http://icarus.stsci.edu/~padovani/
Scientific paper
10.1046/j.1365-8711.2001.04918.x
We present new BeppoSAX observations of seven BL Lacertae objects selected from the 1 Jy sample plus one additional source. The collected data cover the energy range 0.1 - 10 keV (observer's frame), reaching ~ 50 keV for one source (BL Lac). All sources characterized by a peak in their multifrequency spectra at infrared/optical energies (i.e., of the LBL type) display a relatively flat (alpha_x ~ 0.9) X-ray spectrum, which we interpret as inverse Compton emission. Four objects (2/3 of the LBL) show some evidence for a low-energy steepening which is likely due to the synchrotron tail merging into the inverse Compton component around ~ 1 - 3 keV. If this were generally the case with LBL, it would explain why the 0.1 - 2.4 keV ROSAT spectra of our sources are systematically steeper than the BeppoSAX ones (by ~ 0.5 in alpha_x). The broad-band spectral energy distributions fully confirm this picture and a synchrotron inverse Compton model allows us to derive the physical parameters (intrinsic power, magnetic field, etc.) of our sources. Combining our results with those obtained by BeppoSAX on BL Lacs covering a wide range of synchrotron peak frequencies, we confirm and clarify the dependence of the X-ray spectral index on synchrotron peak frequency originally found in ROSAT data.
Comastri Andrea
Costamante Luigi
Ghisellini Gabriele
Giommi Paolo
Maraschi Laura
No associations
LandOfFree
BeppoSAX Observations of 1 Jy BL Lacertae Objects. I 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 BeppoSAX Observations of 1 Jy BL Lacertae Objects. I, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and BeppoSAX Observations of 1 Jy BL Lacertae Objects. I will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-20024