The ATCA HI Galactic Center Survey

TL;DR

This paper presents a detailed survey of atomic hydrogen emission in the Galactic Center region, combining ATCA and Parkes data to provide high-resolution and large-scale coverage of the inner Galactic plane.

Contribution

It introduces a comprehensive HI survey of the Galactic Center with combined interferometric and single-dish data, enhancing resolution and sensitivity over previous surveys.

Findings

Identification of key features like Bania's Clump 2 and the far 3 kpc arm.

Detection of small high velocity clumps.

Enhanced understanding of HI distribution in the Galactic Center.

Abstract

We present a survey of atomic hydrogen HI) emission in the direction of the Galactic Center conducted with the CSIRO Australia Telescope Compact Array (ATCA). The survey covers the area -5 deg < l < +5, -5 deg < b <+5 deg over the velocity range -309 < v_{LSR} < 349 km/s with a velocity resolution of 1 km/s. The ATCA data are supplemented with data from the Parkes Radio Telescope for sensitivity to all angular scales larger than the 145 arcsec angular resolution of the survey. The mean rms brightness temperature across the field is 0.7 K, except near (l,b)=(0 deg, 0 deg) where it increases to ~2 K. This survey complements the Southern Galactic Plane Survey to complete the continuous coverage of the inner Galactic plane in HI at ~2 arcmin resolution. Here we describe the observations and analysis of this Galactic Center survey and present the final data product. Features such as Bania's Clump 2, the far 3 kiloparsec arm and small high velocity clumps are briefly described.