CLASH: EXTENDING GALAXY STRONG LENSING TO SMALL PHYSICAL SCALES WITH DISTANT SOURCES HIGHLY MAGNIFIED BY GALAXY CLUSTER MEMBERS

• Published in: The Astrophysical journal Vol. 786; no. 1; pp. 1 - 12
• Main Authors: Grillo, C, Gobat, R, PRESOTTO, V, Balestra, I, Mercurio, A, Rosati, P, Nonino, M, VANZELLA, E, Christensen, L, Graves, G
• Format: Journal Article
• Language: English
• Published: United States 01.05.2014
• Subjects: Angular resolution; APPROXIMATIONS; ASTROPHYSICS; ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; Clusters; COMPARATIVE EVALUATIONS; DISPERSIONS; Galactic clusters; GALAXIES; GALAXY CLUSTERS; GRAVITATIONAL LENSES; Lenses; LUMINOSITY; MASS; MASS DISTRIBUTION; NONLUMINOUS MATTER; Photometry; RED SHIFT; RESOLUTION; SPHERES; VELOCITY
• ISSN: 0004-637X; 1538-4357
• DOI: 10.1088/0004-637X/786/1/11

We present a complex strong lensing system in which a double source is imaged five times by two early-type galaxies. We use a photometric redshift value of 3.7 for the source and confirm spectroscopically the membership of the two lenses to the galaxy cluster MACS J1206.2-0847 at redshift 0.44. We exploit the excellent angular resolution of the HST/ACS images to model the two lenses in terms of singular isothermal sphere profiles and derive robust effective velocity dispersion values of 97 + or - 3 and 240 + or - 6 km s super(-1). Interestingly, the total mass distribution of the cluster is also well characterized by using only the local information contained in this lensing system, which is located at a projected distance of more than 300 kpc from the cluster luminosity center. These studies, made possible thanks to the CLASH survey, will allow us to go beyond the current limits posed by the available lens samples in the field.