A Very Large (theta(E) greater than or similar to 40 '') Strong Gravitational Lens Selected with the Sunyaev-Zel'dovich Effect: PLCK G287.0+32.9 (z=0.38)

Zitrin, Adi; Seitz, Stella; Monna, Anna; Koekemoer, Anton M.; Nonino, Mario; Grün, Daniel; Balestra, Italo; Girardi, Marisa; Koppenhöfer, Johannes und Mercurio, Amata (2017): A Very Large (theta(E) greater than or similar to 40 '') Strong Gravitational Lens Selected with the Sunyaev-Zel'dovich Effect: PLCK G287.0+32.9 (z=0.38). In: Astrophysical Journal Letters, Bd. 839, Nr. 1, L11

Abstract

Since galaxy clusters sit at the high end of the mass function, the number of galaxy clusters both massive and concentrated enough to yield particularly large Einstein radii poses useful constraints on cosmological and structure formation models. To date, less than a handful of clusters are known to have Einstein radii exceeding similar to 40 '' (for a source at z(s) similar or equal to 2, nominally). Here, we report an addition to that list of the Sunyaev-Zel'dovich (SZ) selected cluster, PLCK G287.0+32.9 (z = 0.38), the second-highest SZ-mass (M-500) cluster from the Planck catalog. We present the first strong-lensing analysis of the cluster, identifying 20 sets of multiply imaged galaxies and candidates in new Hubble Space Telescope (HST) data, including a long, l similar to 22 '' giant arc, as well as a quadruply imaged, apparently bright (magnified to J(F110W) = 25.3 AB), likely high-redshift dropout galaxy at z(phot) = 6.90 [6.13-8.43] (95% C.I.). Our analysis reveals a very large critical area (1.55 arcmin(2), zs similar or equal to 2), corresponding to an effective Einstein radius of theta(E) similar to 42 ''. The model suggests the critical area will expand to 2.58 arcmin(2) (theta(E) similar to 54 '') for sources at z(s) similar to 10. Our work adds to recent efforts to model very massive clusters toward the launch of the James Webb Space Telescope, in order to identify the most useful cosmic lenses for studying the early universe. Spectroscopic redshifts for the multiply imaged galaxies and additional HST data will be necessary for refining the lens model and verifying the nature of the z similar to 7 dropout.

• Dokumententyp: Zeitschriftenartikel
• Fakultät: Physik
• Themengebiete: 500 Naturwissenschaften und Mathematik > 530 Physik
• ISSN: 2041-8205
• Sprache: Englisch