7 papers
The FORS Deep Field
J. Heidt, I. Appenzeller, R. Bender +20
Dedicating a major fraction of its guaranteed time, the FORS consortium established a FORS Deep Field which contains a known QSO at z = 3.36. It was imaged in UBgRIz with FORS at t…
1ES 1741+196: a BL Lacertae object in a triplet of interacting galaxies?
J. Heidt, K. Nilsson, J. W. Fried +2
We present subarcsecond resolution imaging and spectroscopy of the BL Lac object 1ES 1741+196 and neighboring galaxies. Based on 2-dimensional modelling, the host galaxy of 1ES 174…
Unusual radio variability in the BL Lac object 0235+164
A. Kraus, A. Quirrenbach, A. P. Lobanov +11
We present radio observations at three frequencies and contemporaneous optical monitoring of the peculiar BL Lac object AO 0235+164. During a three-week campaign with the VLA we ob…
Host galaxies and environment of BL Lac objects
J. Heidt
Since the last meeting on BL Lac objects 10 years ago, BL Lac host galaxies and their cluster environment have gained much attention. Hence, our current knowledge of the properties…
The optical/IR counterpart of the 3 July 1998 gamma-ray burst and its evolution
A. J. Castro-Tirado, M. R. Zapatero-Osorio, J. Gorosabel +21
We imaged the X-ray error box of GRB 980703, beginning 22.5 hours after the gamma--ray event, in both the optical R and near-infrared H bands. A fading optical/IR object was detect…
High-resolution imaging of Einstein Slew Survey BL Lacertae objects
J. Heidt, K. Nilsson, A. Sillanpaeae +2
High-resolution images of 7 newly identified BL Lac objects (among them one BL Lac candidate) at z < 0.2 from the Einstein Slew Survey are presented for the first time. In all case…