| Issue |
A&A
Volume 421, Number 1, July I 2004
|
|
|---|---|---|
| Page(s) | 83 - 89 | |
| Section | Extragalactic astronomy | |
| DOI | https://doi.org/10.1051/0004-6361:20034449 | |
| Published online | 11 June 2004 | |
Optical variability of PKS 0736+017
1
Instituto de Astronomía, UNAM, Apdo. 70-264, Ciudad Universitaria, 04510 México, D.F., México e-mail: [aramirez;jdo;deborah]@astroscu.unam.mx
2
Universität Hamburg, Hamburger Sternwarte, Gojenbergsweg 112, 21029, Hamburg, Germany
3
Instituto de Astrofísica de Canarias, 38200 La Laguna, Tenerife, Spain e-mail: st1h317@hs.uni-hamburg.de
Corresponding author: A. Ramírez, aramirez@astroscu.unam.mx
Received:
6
October
2003
Accepted:
29
November
2003
We present BVR photometric observations of the blazar PKS 0736+017. These observations were carried out with three telescopes in Mexico and two in Spain between December 1998 and April 2003. PKS 0736+017 shows remarkable variation at different timescales and amplitudes. Maximum brightness was detected on December 19, 2001
(
, 
, and 
). A peculiar tendency to redden with increased brightness was detected throughout our observations. Moreover, in one season a good correlation between flux level and spectral slope is shown.
This anomalous behaviour cannot be described by common flare models of blazars. The flux vs. spectral slope correlation observed in this and other blazars is worth further study.
Key words: Blazar / PKS 0736+017 / radiation mechanisms / variability
© ESO, 2004
Current usage metrics show cumulative count of Article Views (full-text article views including HTML views, PDF and ePub downloads, according to the available data) and Abstracts Views on Vision4Press platform.
Data correspond to usage on the plateform after 2015. The current usage metrics is available 48-96 hours after online publication and is updated daily on week days.
Initial download of the metrics may take a while.