1999/04/30 by Lin Yan, Patrick J. McCarthy, Wolfram Freudling +7 · 4 citations
Physics and Astronomy · #Astrophysics and Star Formation Studies #Galaxies: Formation, Evolution, Phenomena #Stellar, planetary, and galactic studies #astro-ph
paper · pdf · doi:10.1086/312099
11 pages, 2 postscript figures. Accepted for the publication in the ApJ Letters
arxiv created 1999/04/30 · openalex publication_date 1999/07/01 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/07/31
We present a luminosity function for Hα emission from galaxies at redshifts between 0.7 and 1.9 based on slitless spectroscopy with the near-infrared camera and multiobject spectrometer on the Hubble Space Telescope . The luminosity function is well fit by a Schechter function over the range 6 × 10 41 < L 41 < 2 × 10 43 ergs s -1 with L * = 7 × 10 42 ergs s -1 and ϕ* = 1.7 × 10 -3 Mpc -3 for H 0 = 50 km s -1 Mpc -1 and q 0 = 0.5. We derive a volume-averaged star formation rate at z = 1.3 ± 0.5 of 0.13 M ☉ yr -1 Mpc -3 without correction for extinction. The star formation rate that we derive at ~6500 Å is a factor of 3 higher than that deduced from 2800 Å continua. If this difference is caused entirely by reddening, the extinction correction at 2800 Å is quite significant. The precise magnitude of the total extinction correction at rest-frame UV wavelengths (e.g., 2800 and 1500 Å) is sensitive to the relative spatial distribution of the stars, gas, and dust, as well as to the extinction law. In the extreme case of a homogeneous foreground dust screen and a Milky Way or LMC extinction law, we derive a total extinction at 2800 Å of 2.1 mag, or a factor of 7 correction to the UV luminosity density. If we use the Calzetti reddening curve, which was derived for the model in which stars, gas, and dust are well mixed and nebular gas suffers more extinction than stars, our estimate of A 2800 is increased by more than 1 mag.