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The sizes of disc galaxies in intermediate-redshift clusters

S. P. Bamford·B. Milvang-Jensen·A. Aragón-Salamanca
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Abstract

We examine how the location of star formation within disc galaxies depends on environment at intermediate redshift. This is achieved by comparing emission-line (r_em) and restframe B-band (r_B) scalelengths for matched samples of 50 field and 19 cluster star-forming, disc galaxies, with 0.25 < z < 1.0 and M_B < -19.5 mag. We find that at a given r_B the majority of our cluster galaxies have r_em smaller than those in the field, by 25 percent on average. These results are compared with studies of local galaxies, which find a very similar behaviour. From the relations of r_em and r_B versus B-band absolute magnitude (M_B) we infer that the difference between the intermediate-z cluster and field samples is mostly attributable to variation in r_em at a given M_B, while the r_B versus M_B relation is similar for the two samples.

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S. P. Bamford, B. Milvang-Jensen, A. Aragón-Salamanca. 2007-02-27. The sizes of disc galaxies in intermediate-redshift clusters. https://doi.org/10.1111/j.1745-3933.2007.00307.x

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