A Population of Metal-Poor Galaxies with ~L* Luminosities at Intermediate Redshifts

Details A Population of Metal-Poor Galaxies with ~L* Luminosities at Intermediate Redshifts A Population of Metal-Poor Galaxies with ~L* Luminosities at Intermediate Redshifts

2009-03-23

arxiv.org/abs/0903.3948v1

Astronomy and Astrophysics

Astrophysics

Cosmology and Extragalactic Astrophysics

6 pages, 3 figures; to appear in 10 April 2009 ApJL

Scientific paper

10.1088/0004-637X/695/1/L67

We present new spectroscopy and metallicity estimates for a sample of 15 star-forming galaxies with redshifts in the range 0.29 - 0.42. These objects were selected in the KPNO International Spectroscopic Survey via their strong emission lines seen in red objective-prism spectra. Originally thought to be intermediate-redshift Seyfert 2 galaxies, our new spectroscopy in the far red has revealed these objects to be metal-poor star-forming galaxies. These galaxies follow a luminosity-metallicity (L-Z) relation that parallels the one defined by low-redshift galaxies, but is offset by a factor of more than ten to lower abundances. The amount of chemical and/or luminosity evolution required to place these galaxies on the local L-Z relation is extreme, suggesting that these galaxies are in a very special stage of their evolution. They may be late-forming massive systems, which would challenge the current paradigm of galaxy formation. Alternatively, they may represent intense starbursts in dwarf-dwarf mergers or a major infall episode of pristine gas into a pre-existing galaxy. In any case, these objects represent an extreme stage of galaxy evolution taking place at relatively low redshift.

Affiliated with

Also associated with

No associations

Rating

A Population of Metal-Poor Galaxies with ~L* Luminosities at Intermediate Redshifts 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 A Population of Metal-Poor Galaxies with ~L* Luminosities at Intermediate Redshifts, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and A Population of Metal-Poor Galaxies with ~L* Luminosities at Intermediate Redshifts will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-346774