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We report the discovery of seven new, very bright gravitational lens systems from our ongoing gravitational lens search, the Sloan Bright Arcs Survey (SBAS). Two of the systems are confirmed to have high source redshifts z=2.19 and z=2.94. Three othe r systems lie at intermediate redshift with z=1.33,1.82,1.93 and two systems are at low redshift z=0.66,0.86. The lensed source galaxies in all of these systems are bright, with i-band magnitudes ranging from 19.73-22.06. We present the spectrum of each of the source galaxies in these systems along with estimates of the Einstein radius for each system. The foreground lens in most systems is identified by a red sequence based cluster finder as a galaxy group; one system is identified as a moderately rich cluster. In total the SBAS has now discovered 19 strong lens systems in the SDSS imaging data, 8 of which are among the highest surface brightness zsimeq2-3 galaxies known.
We present new results of our program to systematically search for strongly lensed galaxies in the Sloan Digital Sky Survey (SDSS) imaging data. In this study six strong lens systems are presented which we have confirmed with follow-up spectroscopy a nd imaging using the 3.5m telescope at the Apache Point Observatory. Preliminary mass models indicate that the lenses are group-scale systems with velocity dispersions ranging from 466-878 km s^{-1} at z=0.17-0.45 which are strongly lensing source galaxies at z=0.4-1.4. Galaxy groups are a relatively new mass scale just beginning to be probed with strong lensing. Our sample of lenses roughly doubles the confirmed number of group-scale lenses in the SDSS and complements ongoing strong lens searches in other imaging surveys such as the CFHTLS (Cabanac et al 2007). As our arcs were discovered in the SDSS imaging data they are all bright ($rlesssim22$), making them ideally suited for detailed follow-up studies.
We present a semi-automated method to search for strong galaxy-galaxy lenses in optical imaging surveys. Our search technique constrains the shape of strongly lensed galaxies (or arcs) in a multi-parameter space, which includes the third order (octop ole) moments of objects. This method is applied to the Deep Lens Survey (DLS), a deep ground based weak lensing survey imaging to $Rsim26$. The parameter space of arcs in the DLS is simulated using real galaxies extracted from deep HST fields in order to more accurately reproduce the properties of arcs. Arcs are detected in the DLS using a pixel thresholding method and candidate arcs are selected within this multi-parameter space. Examples of strong galaxy-galaxy lens candidates discovered in the DLS F2 field (4 square degrees) are presented.
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