Spectroscopic observations with the Gemini Multi-Object Spectrograph at Gemini South provide precise redshifts that confirm strong gravitational lensing systems discovered in early Dark Energy Survey ( DES ) data . These confirmations are the first at galaxy- and galaxy-cluster scales in the multi-year effort of lens follow-up enabled by a Large and Long program .
Brian Nord and Elizabeth Buckley-Geer
July 2016
A Case of Warped Space :
Confirming Strong Gravitational Lenses Found in the Dark Energy Survey
Spectroscopic observations with the Gemini Multi-Object Spectrograph at Gemini South provide precise redshifts that confirm strong gravitational lensing systems discovered in early Dark Energy Survey ( DES ) data . These confirmations are the first at galaxy- and galaxy-cluster scales in the multi-year effort of lens follow-up enabled by a Large and Long program .
Massive astronomical objects sufficiently warp space-time to change the path of light on its way from distant galaxies to an observer . Consequently , strong gravitational lensing systems are revealed to us by the distorted images of these galaxies .
Most of the strong lensing systems discovered during the last decade were found by searching through existing data or through new observational campaigns . These investigations across many wavebands — from the optical to the millimeter — have resulted in ~ 1,000 candidates or confirmed lensing systems of varying masses , with distorted galaxy images in arcs of varying sizes around them .
The Dark Energy Survey ( DES ; @ TheDESurvey ) — an ongoing international , collaborative effort to produce the largest and deepest contiguous map of the southern sky to date in optical wavelengths — has the potential to add to the roster twice as many strong lenses in the optical as have ever been discovered across all wavelengths .
January 2017 | 2016 Year in Review GeminiFocus
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