VLA 1.4 GHz Catalogs of the Abell 370 and Abell 2390 Cluster Fields

TL;DR

This paper presents deep 1.4 GHz radio catalogs for the Abell 370 and Abell 2390 galaxy clusters, including detailed imaging, redshift data, and analysis of radio source counts, highlighting the impact of cosmic variance.

Contribution

First deep 1.4 GHz radio catalogs for Abell 370 and Abell 2390, with analysis of source counts and cosmic variance effects.

Findings

Faint radio counts in Abell 370 match high blank field counts.

Faint radio counts in Abell 2390 match low blank field counts.

Number counts are mainly from field radio galaxies, affected by cosmic variance.

Abstract

We present 1.4 GHz catalogs for the cluster fields Abell 370 and Abell 2390 observed with the Very Large Array. These are two of the deepest radio images of cluster fields ever taken. The Abell 370 image covers an area of 40'x40' with a synthesized beam of ~1.7" and a noise level of ~5.7 uJy near field center. The Abell 2390 image covers an area of 34'x34' with a synthesized beam of ~1.4" and a noise level of ~5.6 uJy near field center. We catalog 200 redshifts for the Abell 370 field. We construct differential number counts for the central regions (radius < 16') of both clusters. We find that the faint (S_1.4GHz < 3 mJy) counts of Abell 370 are roughly consistent with the highest blank field number counts, while the faint number counts of Abell 2390 are roughly consistent with the lowest blank field number counts. Our analyses indicate that the number counts are primarily from field radio galaxies. We suggest that the disagreement of our counts can be largely attributed to cosmic variance.