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We present the first study of large-scale bars in clusters at intermediate redshifts (z=0.4-0.8). We compare the properties of the bars and their host galaxies in the clusters with those of a field sample in the same redshift range. We use a sample of 945 moderately inclined disk galaxies drawn from the EDisCS project. The morphological classification of the galaxies and the detection of bars are based on deep HST/ACS F814W images. The total optical bar fraction in the redshift range z=0.4-0.8, averaged over the entire sample, is 25%. This is lower than found locally, but in good agreement with studies of bars in field environments at intermediate redshifts. For the cluster and field subsamples, we measure bar fractions of 24% and 29%, respectively. In agreement with local studies, we find that disk-dominated galaxies have a higher bar fraction than bulge-dominated galaxies. We also find, based on a small subsample, that bars in clusters are on average longer than in the field and preferentially found close to the cluster center, where the bar fraction is somewhat higher than at larger distances.
We present a study of large-scale bars in field and cluster environments out to redshifts of ~0.8 using a final sample of 945 moderately inclined disk galaxies drawn from the EDisCS project. We characterize bars and their host galaxies and look for r
Herschel has opened new windows into studying the evolution of rapidly star-forming galaxies out to high redshifts. Todays massive starbursts are characterized by star formation rates (SFRs) of 100+ Mo/yr and display a chaotic morphology and nucleate
The nature of absorption-selected galaxies and their connection to the general galaxy population have been open issues for more than three decades, with little information available on their gas properties. Here we show, using detections of carbon mo
We select E+A candidates from a spectroscopic dataset of ~800 field galaxies and measure the E+A fraction at 0.3<z<1 to be 2.7+/-1.1%, a value lower than that in galaxy clusters at comparable redshifts (11+/-3%). HST/WFPC2 imaging for five of our six
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