The WSRT ZoA Perseus-Pisces Filament wide-field HI imaging survey I. HI catalogue and atlas

TL;DR

This survey used the Westerbork Synthesis Radio Telescope to map a galaxy overdensity behind the Milky Way, resulting in a catalogue of 211 HI-detected galaxies and insights into the structure of the Perseus-Pisces filament.

Contribution

First wide-field HI imaging survey of the Zone-of-Avoidance crossing the Perseus-Pisces filament, providing detailed HI catalogues and maps of galaxies in this obscured region.

Findings

Detected 211 galaxies with HI emission, 62% with near-infrared counterparts.

Identified galaxy structures associated with the Perseus-Pisces Supercluster and a secondary overdensity.

Mapped the HI properties and velocity fields of galaxies in a previously underexplored region.

Abstract

We present results of a blind 21cm HI-line imaging survey of a galaxy overdensity located behind the Milky Way at $\ell,b$ $\approx$ 160 deg, 0.5 deg. The overdensity corresponds to a Zone-of-Avoidance crossing of the Perseus-Pisces Supercluster filament. Although it is known that this filament contains an X-ray galaxy cluster (3C129) hosting two strong radio galaxies, little is known about galaxies associated with this potentially rich cluster because of the high Galactic dust extinction. We mapped a sky area of $\sim$9.6 sq.deg using the Westerbork Synthesis Radio Telescope in a hexagonal mosaic of 35 pointings observed for 12 hours each, in the radial velocity range $cz = 2400 - 16600$ km/s. The survey has a sensitivity of 0.36 mJy/beam rms at a velocity resolution of 16.5 km/s. We detected 211 galaxies, 62% of which have a near-infrared counterpart in the UKIDSS Galactic Plane Survey. We present a catalogue of the HI properties and an HI atlas containing total intensity maps, position-velocity diagrams, global HI profiles and UKIDSS counterpart images. For the resolved galaxies we also present HI velocity fields and radial HI surface density profiles. A brief analysis of the structures outlined by these galaxies finds that 87 of them lie at the distance of the Perseus-Pisces Supercluster ($cz \sim 4000 - 8000$ km/s) and seem to form part of the 3C129 cluster. Further 72 detections trace an overdensity at a velocity of $cz \approx$ 10000 km/s and seem to coincide with a structure predicted from mass density reconstructions in the first 2MASS Redshift Survey.