TY - JOUR
T1 - A comparison of independent star formation diagnostics for an ultraviolet-selected sample of nearby galaxies
AU - Sullivan, Mark
AU - Mobasher, Bahram
AU - Chan, Ben
AU - Cram, Lawrence
AU - Ellis, Richard
AU - Treyer, Marie
AU - Hopkins, Andrew
PY - 2001/9/1
Y1 - 2001/9/1
N2 - We present results from a decimetric radio survey undertaken with the Very Large Array as part of a longer term goal to intercompare star formation and dust extinction diagnostics on a galaxy-by-galaxy basis for a representative sample of nearby galaxies. For our survey field, Selected Area 57, star formation rates derived from 1.4 GHz luminosities are compared with earlier nebular emission-line and ultraviolet (UV) continuum diagnostics. We find broad correlations, over several decades in luminosity, between the Hα, UV continuum, and 1.4 GHz diagnostics. However, the scatter in these relations is found to be larger than observational errors, with offsets between the observed relations and those expected assuming constant star formation histories and luminosity-independent extinction models. We investigate the physical origin of the observed relations and conclude that the discrepancies between different star formation diagnostics can only be partly explained by simple models of dust extinction in galaxies. These models cannot by themselves explain all the observed differences, introducing the need for temporally varying star formation histories and/or more complex models of extinction to explain the entire data set.
AB - We present results from a decimetric radio survey undertaken with the Very Large Array as part of a longer term goal to intercompare star formation and dust extinction diagnostics on a galaxy-by-galaxy basis for a representative sample of nearby galaxies. For our survey field, Selected Area 57, star formation rates derived from 1.4 GHz luminosities are compared with earlier nebular emission-line and ultraviolet (UV) continuum diagnostics. We find broad correlations, over several decades in luminosity, between the Hα, UV continuum, and 1.4 GHz diagnostics. However, the scatter in these relations is found to be larger than observational errors, with offsets between the observed relations and those expected assuming constant star formation histories and luminosity-independent extinction models. We investigate the physical origin of the observed relations and conclude that the discrepancies between different star formation diagnostics can only be partly explained by simple models of dust extinction in galaxies. These models cannot by themselves explain all the observed differences, introducing the need for temporally varying star formation histories and/or more complex models of extinction to explain the entire data set.
KW - Galaxies: Evolution
KW - Galaxies: Starburst
KW - Radio continuum: Galaxies
KW - Stars: Formation
KW - Surveys
KW - Ultraviolet: Galaxies
UR - http://www.scopus.com/inward/record.url?scp=0035457277&partnerID=8YFLogxK
U2 - 10.1086/322451
DO - 10.1086/322451
M3 - Review article
AN - SCOPUS:0035457277
SN - 0004-637X
VL - 558
SP - 72
EP - 80
JO - Astrophysical Journal
JF - Astrophysical Journal
IS - 1 PART 1
ER -