A New Window of Exploration in the Mass Spectrum: Strong Lensing by Galaxy Groups in the SL2S

Understand

The existence of strong lensing systems with Einstein radii (Re) covering the full mass spectrum, from ~1-2" (produced by galaxy scale dark matter haloes) to >10" (produced by galaxy cluster scale haloes) have long been predicted.

• Many lenses with Re around 1-2" and above 10" have been reported but very few in between.
• In this article, we present a sample of 13 strong lensing systems with Re in the range 3"- 8", i.e.
• systems produced by galaxy group scale dark matter haloes, spanning a redshift range from 0.3 to 0.8.