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NOAO < SURVEY-ARCHIVES < Survey Archives - Survey for Ionization in Neutral Gas Galaxies

The Survey for Ionization in Neutral Gas Galaxies


The Survey for Ionization in Neutral-Gas Galaxies (SINGG) is an NOAO survey program to measure the emission from ionized hydrogen in a subset of the galaxies found by the 21cm HI Parkes All Sky Survey (HIPASS). The survey examines 500 HIPASS galaxies chosen to uniformly cover the HI mass function. Each galaxy was imaged in Hα and the R-band stellar continuum at the CTIO 1.5m telescope. The Hα emission line, at rest wavelength 6563 Angstroms, traces the ionized medium (HII), which in turn traces high-mass, recently-formed stars that ionize this gas. Since a gaseous medium is a prerequisite for star formation, this survey will uniformly sample all galaxies that could form stars and hence will provide a relatively unbiased view of the local star formation demographics. The scientific goals of SINGG are:

  1. to estimate how many stars are forming per year per unit volume of the local universe and compare this result to other measures of the global star formation rate;
  2. provide a census of star formation morphologies in the local universe;
  3. study properties of the HII region luminosity function for the full range of gas rich galaxies;
  4. determine the distribution of star formation rates as a function of various optical and HI properties (e.g. luminosity, HI mass, velocity dispersion; and
  5. estimate the epoch when the star formation in the local universe will exhaust its gas supply. The SINGG database will provide a reference Hα survey of the local universe, and a rich resource for research into the star formation process in galaxies.

SINGG at a Glance

PI(s) Gerhardt Meurer
Proposal ID 2000B-0032
Years of Observation 2000-2004
Sample: 93 HI-selected low-z galaxies
Bands R, Hα
Median Depth (5σ) R = 23.2
Median Seeing R = 1.6 arcsec
Number of images 278, includes R-band, Hα, and Hα-R difference images.