CASSOWARY 20: a Wide Separation Einstein Cross Identified with the X-shooter Spectrograph

Details CASSOWARY 20: a Wide Separation Einstein Cross Identified with the X-shooter Spectrograph CASSOWARY 20: a Wide Separation Einstein Cross Identified with the X-shooter Spectrograph

2009-09-17

arxiv.org/abs/0909.3301v2

Astronomy and Astrophysics

Astrophysics

Cosmology and Extragalactic Astrophysics

10 pages, 7 Figures, Accepted for publication in Monthly Notices of the Royal Astronomical Society after minor revisions

Scientific paper

We have used spectra obtained with X-shooter, the triple arm optical-infrared spectrograph recently commissioned on the Very Large Telescope of the European Southern Observatory, to confirm the gravitational lens nature of the CASSOWARY candidate CSWA 20. This system consists of a luminous red galaxy at redshift z(abs) = 0.741, with a very high velocity dispersion sigma(lens) = 500 km/s, which lenses a blue star-forming galaxy at z(em) = 1.433 into four images with mean separation of about 6 arcseconds. The source shares many of its properties with those of UV-selected galaxies z = 2-3: it is forming stars at a rate of 25 solar masses per year, has a metallicity of about 1/4 solar, and shows nebular emission from two components separated by 0.4 arcseconds in the image plane, possibly indicating a merger. It appears that foreground interstellar material within the galaxy has been evacuated from the sight-line along which we observe the starburst, giving an unextinguished view of its stars and H II regions. CSWA 20, with its massive lensing galaxy producing a high magnification of an intrinsically luminous background galaxy, is a promising target for future studies at a variety of wavelengths.

Affiliated with

Also associated with

No associations

Rating

CASSOWARY 20: a Wide Separation Einstein Cross Identified with the X-shooter Spectrograph does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with CASSOWARY 20: a Wide Separation Einstein Cross Identified with the X-shooter Spectrograph, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and CASSOWARY 20: a Wide Separation Einstein Cross Identified with the X-shooter Spectrograph will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-275795