CLASH: THE ENHANCED LENSING EFFICIENCY OF THE HIGHLY ELONGATED MERGING CLUSTER MACS J0416.1-2403

Journal Article · Thu Jan 10 00:00:00 EST 2013 · Astrophysical Journal Letters

DOI:https://doi.org/10.1088/2041-8205/762/2/L30· OSTI ID:22078336

Zitrin, A; Bartelmann, M; Carrasco, M ^[1]; Meneghetti, M ^[2]; Umetsu, K ^[3]; Broadhurst, T ^[4]; Bouwens, R ^[5]; Bradley, L; Coe, D; Koekemoer, A M; Postman, M ^[6]; Ford, H; Medezinski, E ^[7]; Kelson, D ^[8]; Moustakas, J ^[9]; Moustakas, L A ^[10]; Nonino, M ^[11]; Rosati, P ^[12]; Seidel, G ^[13]; Seitz, S ^[14] ; others, and

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1. Institut fuer Theoretische Astrophysik, Zentrum fuer Astronomie, Universitaet Heidelberg, Philosophenweg 12, D-69120 Heidelberg (Germany)
2. INAF, Osservatorio Astronomico di Bologna, and INFN, Sezione di Bologna, Via Ranzani 1, I-40127 Bologna (Italy)
3. Institute of Astronomy and Astrophysics, Academia Sinica, P.O. Box 23-141, Taipei 10617, Taiwan (China)
4. Department of Theoretical Physics, University of Basque Country UPV/EHU, P.O. Box 644, E-48080 Bilbao (Spain)
5. Leiden Observatory, Leiden University, NL-2300 RA Leiden (Netherlands)
6. Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21208 (United States)
7. Department of Physics and Astronomy, The Johns Hopkins University, 3400 North Charles Street, Baltimore, MD 21218 (United States)
8. Observatories of the Carnegie Institution of Washington, Pasadena, CA 91101 (United States)
9. Department of Physics and Astronomy, Siena College, Loudonville, NY 12211 (United States)
10. Jet Propulsion Laboratory, California Institute of Technology, MS 169-327, Pasadena, CA 91109 (United States)
11. INAF-Osservatorio Astronomico di Trieste, via G.B. Tiepolo 11, I-40131 Trieste (Italy)
12. ESO-European Southern Observatory, D-85748 Garching bei Muenchen (Germany)
13. Max-Planck-Institute for Astronomy, Koenigstuhl 17, D-69117 Heidelberg (Germany)
14. University Observatory Munich, Scheinerstrasse 1, D-81679 Muenchen (Germany)

We perform a strong lensing analysis of the merging galaxy cluster MACS J0416.1-2403 (M0416; z = 0.42) in recent CLASH/HST observations. We identify 70 new multiple images and candidates of 23 background sources in the range 0.7 {approx}< z{sub phot} {approx}< 6.14 including two probable high-redshift dropouts, revealing a highly elongated lens with axis ratio {approx_equal}5:1, and a major axis of {approx}100'' (z{sub s} {approx} 2). Compared to other well-studied clusters, M0416 shows an enhanced lensing efficiency. Although the critical area is not particularly large ({approx_equal} 0.6 {open_square}'; z{sub s} {approx} 2), the number of multiple images, per critical area, is anomalously high. We calculate that the observed elongation boosts the number of multiple images, per critical area, by a factor of {approx}2.5 Multiplication-Sign , due to the increased ratio of the caustic area relative to the critical area. Additionally, we find that the observed separation between the two main mass components enlarges the critical area by a factor of {approx}2. These geometrical effects can account for the high number (density) of multiple images observed. We find in numerical simulations that only {approx}4% of the clusters (with M{sub vir} {>=} 6 Multiplication-Sign 10{sup 14} h {sup -1} M{sub Sun }) exhibit critical curves as elongated as in M0416.

• OSTI ID: 22078336
• Journal Information: Astrophysical Journal Letters, Vol. 762, Issue 2; Other Information: Country of input: International Atomic Energy Agency (IAEA); ISSN 2041-8205
• Country of Publication: United States
• Language: English

Related Subjects

79 ASTROPHYSICS
COSMOLOGY AND ASTRONOMY
COMPUTERIZED SIMULATION
DIAGRAMS
EFFICIENCY
ELONGATION
GALAXY CLUSTERS
IMAGES
LENSES
MASS
RED SHIFT