Near infrared monitoring of a sample of blazars with the Carlos Sanchez Telescope.

Takalo, L. O.; Kidger, M. R.; de Diego, Jose A.; Sillanpaa, Aimo; Nilsson, Kari
Bibliographical reference

Astronomical Journal (ISSN 0004-6256), vol. 104, no. 1, July 1992, p. 40-52.

Advertised on:
7
1992
Number of authors
5
IAC number of authors
2
Citations
55
Refereed citations
55
Description
Results of a program of near-IR monitoring of a sample of blazars and miniblazars observed during 1990 and 1991 with the Carlos Sanchez Telescope, in Teide Observatory, Tenerife are presented. All of the objects in the sample show blazar activity during the course of the observations. Several of the objects in the sample have been monitored for rapid variations on timescales of a few hours; only one of them has not, to date, shown such activity. Markarian 421, Markarian 501, 3C273, and AO 0235 + 164 show evidence of possible color variations, although only in Markarian 501 and AO 0235 + 164 are these color changes beyond doubt. One object, 3C345, unlike other blazars, shows a flatter spectrum when fainter, confirming previously published results.