Astronomy and Astrophysics – Astrophysics
Scientific paper
1999-08-16
Astronomy and Astrophysics
Astrophysics
13 Pages with 4 Figures; Accepted for Publication by the Astrophysical Journal
Scientific paper
10.1086/308217
The BL-Lac family of active galaxies possess almost featureless spectra and exhibit rapid variability over their entire spectral range. A number of models have been developed to explain these extreme properties, several of which have invoked the action of microlensing by sub-stellar mass objects in a foreground galaxy; this not only introduces variability, but also amplifies an otherwise normal quasar source. Here we present recent spectroscopy and photometry of the southern BL Lac PKS 0537-441; with an inferred redshift of z~0.9 it represents one of the most distant and most luminous members of the BL Lac family. The goal of the observations was not only to confirm the redshift of PKS~0537-441, but also to determine the redshift of a putative galaxy along the line of sight to the BL-Lac; it has been proposed that this galaxy is the host of microlensing stars that account for PKS 0537-441's extreme properties. While several observations have failed to detect any extended emission in PKS 0537-441, the HST imaging data presented here indicate the presence of a galactic component, although we fail to identify any absorption features that reveal the redshift of the emission. It is also noted that PKS 0537-441 is accompanied by several small, but extended companions, located a few arcseconds from the point-like BL-Lac source. Two possibilities present themselves; either they represent true companions of PKS 0537-441, or are themselves gravitationally lensed images of more distant sources.
Ibata Rodrigo A.
Lewis Geraint F.
No associations
LandOfFree
An Investigation of Gravitational Lensing in the Southern BL Lac PKS 0537-441 does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with An Investigation of Gravitational Lensing in the Southern BL Lac PKS 0537-441, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and An Investigation of Gravitational Lensing in the Southern BL Lac PKS 0537-441 will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-74894