The Small Isolated Gas Rich Irregular Dwarf (SIGRID) Galaxy Sample: Description and First Results

TL;DR

This paper introduces the SIGRID sample of 83 isolated, gas-rich dwarf galaxies selected via HIPASS, detailing their properties, survey methods, and initial spectroscopic observations to study their chemical abundances.

Contribution

It presents the first results from a new optically-unbiased survey of isolated dwarf galaxies, including sample selection, observational procedures, and initial spectroscopic data.

Findings

Sample consists of 83 isolated, gas-rich dwarf galaxies.

All galaxies show ongoing star formation.

Initial spectroscopic observations are underway for chemical analysis.

Abstract

Using an optically-unbiased selection process based on the HIPASS neutral hydrogen survey, we have selected a sample of 83 spatially isolated, gas-rich dwarf galaxies in the southern hemisphere with cz between 350 and 1650 km s-1, and with R-band luminosities and HI masses less than that of the Small Magellanic Cloud. The sample is an important population of dwarf galaxies in the local Universe, all with ongoing star formation, and most of which have no existing spectroscopic data. We are measuring the chemical abundances of these galaxies, using the Integral Field Spectrograph on the ANU 2.3m telescope, the Wide Field Spectrograph (WiFeS). This paper describes our survey criteria and procedures, lists the survey sample, and reports on initial observations.