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Title: Discovery of two gravitationally lensed quasars in the Dark Energy Survey

In this study, we present spectroscopic confirmation of two new lensed quasars via data obtained at the 6.5m Magellan/Baade Telescope. The lens candidates have been selected from the Dark Energy Survey (DES) and WISE based on their multi-band photometry and extended morphology in DES images. Images of DES J0115-5244 show two blue point sources at either side of a red galaxy. Our long-slit data confirm that both point sources are images of the same quasar at z s = 1.64. The Einstein Radius estimated from the DES images is 0.51''. DES J2146-0047 is in the area of overlap between DES and the Sloan Digital Sky Survey (SDSS). Two blue components are visible in the DES and SDSS images. The SDSS fiber spectrum shows a quasar component at z s = 2.38 and absorption compatible with Mg II and Fe II at z l = 0.799, which we tentatively associate with the foreground lens galaxy. The long-slit Magellan spectra show that the blue components are resolved images of the same quasar. Furthermore, the Einstein Radius is 0.68'' corresponding to an enclosed mass of 1.6 × 10 11 M . Three other candidates were observed and rejected, two being low-redshift pairs ofmore » starburst galaxies, and one being a quasar behind a blue star. These first confirmation results provide an important empirical validation of the data-mining and model-based selection that is being applied to the entire DES dataset.« less
  1. PAB, Los Angeles, CA (United States). et al.
Publication Date:
Report Number(s):
Journal ID: ISSN 1365-2966; arXiv eprint number arXiv:1508.01203
Grant/Contract Number:
AC02-07CH11359; AC02-76SF00515
Accepted Manuscript
Journal Name:
Monthly Notices of the Royal Astronomical Society (Online)
Additional Journal Information:
Journal Name: Monthly Notices of the Royal Astronomical Society (Online); Journal Volume: 454; Journal Issue: 2; Journal ID: ISSN 1365-2966
Royal Astronomical Society
Research Org:
Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States); SLAC National Accelerator Lab., Menlo Park, CA (United States)
Sponsoring Org:
USDOE Office of Science (SC), High Energy Physics (HEP) (SC-25)
Contributing Orgs:
DES Collaboration
Country of Publication:
United States
74 ATOMIC AND MOLECULAR PHYSICS; gravitational lensing: strong; quasars: emission lines; methods: observational; methods: statistical; 79 ASTRONOMY AND ASTROPHYSICS
OSTI Identifier:
Alternate Identifier(s):
OSTI ID: 1263419