2008/02/27 by Ayesha Begum, Jayaram N. Chengalur, I. D. Karachentsev +2 · 5 citations
Physics and Astronomy · #Astronomy and Astrophysical Research #Dwarf galaxy #Galaxies: Formation, Evolution, Phenomena #Galaxy #Giant Metrewave Radio Telescope #Interstellar medium #Irregular galaxy #Luminosity #Magnitude (astronomy) #Radio Astronomy Observations and Technology #Telescope #astro-ph
paper · pdf · doi:10.1111/j.1365-2966.2008.13150.x
17 pages, 14 figures. Accepted for publication in MNRAS
arxiv created 2008/02/27 · openalex publication_date 2008/04/16 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
The Faint Irregular Galaxies GMRT Survey (FIGGS) is a Giant Metrewave Radio Telescope (GMRT) based H i imaging survey of a systematically selected sample of extremely faint nearby dwarf irregular galaxies. The primary goal of FIGGS is to provide a comprehensive and statistically robust characterization of the neutral interstellar medium properties of faint, gas-rich dwarf galaxies. The FIGGS galaxies represent the extremely low mass end of the dwarf irregular galaxies population, with a median MB∼−13.0 and median H i mass of ∼3 × 107M⊙, extending the baseline in mass and luminosity space for a comparative study of galaxy properties. The H i data are supplemented with observations at other wavelengths. In addition, distances accurate to ∼10 per cent are available for most of the sample galaxies. This paper gives an introduction to FIGGS, describes the GMRT observations and presents the first results from the H i observations. From the FIGGS data, we confirm the trend of increasing H i to optical diameter ratio with decreasing optical luminosity; the median ratio of DH i/DHo for the FIGGS sample is 2.4. Further, on comparing our data with aperture synthesis surveys of bright spirals, we find at best marginal evidence for a decrease in average surface density with decreasing H i mass. To a good approximation, the discs of gas-rich galaxies, ranging over three orders of magnitude in H i mass, can be described as being drawn from a family with fixed H i average surface density.