Andromeda's Parachute: A Bright Quadruply Lensed Quasar at z=2.377

作者：Rubin Kate H R; O'Meara John M; Cooksey Kathy L; Matuszewski Mateusz; Rizzi Luca; Doppmann Greg; Kwok Shui; Martin D Christopher; Moore Anna M; Morrissey Patrick; Neill James D

来源：Astrophysical Journal, 2018, 859(2): 146.

DOI：10.3847/1538-4357/aaaeb7

• gravitational lensing: strong
• intergalactic medium
• quasars: absorption lines
• techniques: imaging spectroscopy

We present Keck Cosmic Web Imager spectroscopy of the four putative images of the lensed quasar candidate J014710 + 463040 recently discovered by Berghea et al. The data verify the source as a quadruply lensed, broad absorption-line quasar having z(S) = 2.377 +/- 0.007. We detect intervening absorption in the Fe lambda lambda 2586, 2600, Mg II lambda lambda 2796, 2803, and/or C IV lambda lambda 1548, 1550 transitions in eight foreground systems, three of which have redshifts consistent with the photometric-redshift estimate reported for the lensing galaxy (z(L) approximate to 0.57). The source images probe these absorbers over transverse physical scales of approximate to 0.3-22 kpc, permitting assessment of the variation in metal-line equivalent width W-r as a function of sight-line separation. We measure differences in W-r,W-2796 of < 40% across most of the sight-line pairs subtending 8-22 kpc, suggestive of a high degree of spatial coherence for the Mg II-absorbing material. W-r,W- 2600 varies by > 50% over the same scales across the majority of sight-line pairs, while C IV absorption exhibits a wide range in W-r, 1548 differences of approximate to 5%-80% within transverse distances of less than or similar to 3 kpc. These spatial variations are consistent with those measured in intervening absorbers detected toward lensed quasars drawn from the literature, in which W-r,W- 2796 and W-r,W- 1548 vary by <= 20% in 35 +/- 7% and 47 +/- 6% of sight lines separated by < 10 kpc, respectively. J014710 + 463040 is one of only a handful of z > 2 quadruply lensed systems for which all four source images are very bright (r = 15.4-17.7 mag) and are easily separated in ground-based seeing conditions. As such, it is an ideal candidate for higher-resolution spectroscopy probing the spatial variation in the kinematic structure and physical state of intervening absorbers.

• 出版日期2018-6-1