2007MNRAS.378L...6B

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 rest-frame 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 per cent 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_Brelation is similar for the two samples.