A Wide Field, Low Frequency Radio Survey of the Field of M31: I. Construction and Statistical Analysis of the Source Catalog

Abstract

We present here the results of a 325 MHz radio survey of M31, conducted with the A-configuration of the Very Large Array. The survey covered an area of 7.6 deg$^2$, and a total of 405 radio sources between $\la$6\arcsec and 170\arcsec in extent were mapped with a resolution of 6\arcsec and a 1$σ$ sensitivity of $\sim$0.6 \mjyb. For each source, its morphological class, major axis $θ_M$, minor axis $θ_m$, position angle $θ_{PA}$, peak flux $I$, integrated flux density $S$, spectral index $α$ and spectral curvature parameter $ϕ$ were calculated. A comparison of the flux and radial distribution -- both in the plane of the sky and in the plane of M31 -- of these sources with those of the XMM--LSS and WENSS radio surveys revealed that a vast majority of sources detected are background radio galaxies. As a result of this analysis, we expect that only a few sources are intrinsic to M31. These sources are identified and discussed in an accompanying paper.

29 pages with 4 tables and 10 figures (JPEGs), accepted for publication in ApJS. Full-resolution images available on request