A&A 391, 917-922 (2002)
Radio luminosities and classificatory criteria of BL Lacertae objectsD. C. Mei, L. Zhang and Z. J. Jiang
Department of Physics, Yunnan University, Kunming 650091, PR China
(Received 17 April 2002 / Accepted 26 June 2002 )
Using the sample of radio-selected BL Lacertae objects (RBLs) and X-ray selected BL Lacertae objects (XBLs) presented by Sambruna et al. (1996), we calculated the luminosities in radio, optical and X-ray of each source and made a statistical analysis among the luminosities at different wave-bands, broad-band spectral indices from radio to X-ray ( ) and peak frequencies ( ). Our results are as follows: (i) there is a positive correlation between radio luminosity and and a negative correlation between and . High-energy peak BL Lacs (HBLs) and low-energy peak BL Lacs (LBLs) can be distinguished very well; the dividing lines are probably those of (erg/s) and (or ) 0.75 for - plot and those of (erg/s) and for the - plot; (ii) there is a weak positive correlation between optical luminosity and and a negative weak correlation between and ; (iii) there is no correlation between X-ray luminosity and or between and . From our analysis, we find that synchrotron radiation is the main X-ray radiation mechanism for HBLs while inverse Compton scattering is dominant for LBLs.
Key words: galaxies: BL Lacertae objects: general -- galaxies: fundamental parameters -- radiation mechanism: non-thermal
Offprint request: D. C. Mei, email@example.com
© ESO 2002