Astron. Astrophys. Suppl. Ser.
Volume 133, Number 2, December I 1998
|Page(s)||217 - 220|
|Published online||15 December 1998|
Infrared variability of BL Lacertae
CCAST (World Laboratory), P.O. Box 8730, Beijing 100080, China
2 Center for Astrophysics, Guangzhou Normal University, Guangzhou 510400, China
3 Yunnan Observatory, Chinese Academy of Sciences, Kunming 650011, China
Accepted: 10 June 1998
In this paper, the historic light curves of BL Lacertae in the infrared (JHK) bands have been constructed from the published literature. Maximum variations of , , and and average color indices of , , and have been found. The relation between the color index and the brightness of the source and the correlation of color-color indices have been investigated. Our analysis shows that there is no clear correlation between the color index and the brightness, and the emission mechanism is non-thermal in the near-infrared.
Key words: infrared: galaxies / BL Lacertae objects: BL Lac
© European Southern Observatory (ESO), 1998