US Naval Observatory | 2017 Jul 24
[img3="Pan-STARRS image of the quadruple gravitational lens candidate. The four images of the quasar are marked A-D. The lensing galaxy is very faint and it was discovered only after careful analysis of the image, its position is marked with an x. Credit: USNO"]https://3c1703fe8d.site.internapcdn.net ... d0bd0a.jpg[/img3][hr][/hr]Astronomers from the United States Naval Observatory (USNO) in conjunction with colleagues from the University of California, Davis, and Rutgers University have discovered the first quadruple gravitational lens candidate within data from the Panoramic Survey Telescope and Rapid Response System (Pan-STARRS) using a combination of all-sky survey data from the USNO Robotic Astrometric Telescope (URAT) and the Wide-field Infrared Survey Explorer (WISE).
USNO graduate student George Nelson, who was performing a URAT variability study of the brightest quasars identified by USNO astronomers using WISE colors, discovered the lens while investigating the optical properties of a bright quasar sample. ...
Since the discovery of the first gravitationally lensed quasar in 1979, gravitational lenses have become powerful probes of astrophysics and cosmology. Because they require a very specific configuration between a background quasar (a bright, distant object powered by a supermassive black hole) and a foreground lensing galaxy, quadruply lensed quasars are especially rare. In fact, to date there are only about three-dozen such objects known over the entire sky. ...
Discovery of the first quadruple gravitationally lensed quasar candidate with Pan-STARRS - C. T. Berghea et al
- arXiv.org > astro-ph > arXiv:1705.08359 > 23 May 2017 (v1), 11 Jul 2017 (v2)
- arXiv.org > astro-ph > arXiv:1707.05873 > 18 Jul 2017