Dust Absorption And The Ultraviolet Luminosity Density At z \approx 3 As Calibrated By Local Starburst Galaxies
| dc.creator | Meurer, Gerhardt R. | |
| dc.creator | Heckman, Timothy M. | |
| dc.creator | Calzetti, Daniela | |
| dc.date | 1999-03-03 | |
| dc.date.accessioned | 2026-07-07T10:51:26Z | |
| dc.date.available | 2026-07-07T10:51:26Z | |
| dc.description | We refine a technique to measure the absorption corrected ultraviolet (UV) luminosity of starburst galaxies using rest frame UV quantities alone, and apply it to U-dropouts at z ~ 3 found in the Hubble Deep Field. The method is based on an observed correlation between the ratio of far infrared (FIR) to UV fluxes with spectral slope β(a UV color). A simple fit to this relation allows the UV flux absorbed by dust to be calculated, and hence the dust-free UV luminosity to be determined. IUE spectra and IRAS fluxes of local starbursts are used to calibrate the ratio in terms of 1600 Angstrom absorption A_{1600}, and the transformation from broad band color to β. We show that the recent marginal and non-detections of HDF U-dropouts in the radio and sub-mm are consistent with our calculated A_{1600}. This is also true of observations of the ratio of optical emission line flux to UV flux density in the brightest U-dropouts. This latter ratio turns out not to be a good indicator of dust extinction. In U-dropouts, absolute magnitude correlates with β: brighter galaxies are redder, as is observed in local starburst galaxies. This suggests that a mass-metallicity relationship is in place by z ~ 3. The UV luminosity function of U-dropouts extends up to M_{1600,0} ~ -24 ABmag corresponding to a star formation rate ~ 200 \Msun/yr (H_0 = 50 km/s/Mpc, q_0 = 0.5). The absorption-corrected UV luminosity density at z ~ 3 is ρ_{1600,0} => 1.4x10^{27} erg/s/Hz/Mpc^3; still a lower limit since completeness corrections have not been done and because only galaxies with A_{1600} < ~3.6 mag are blue enough to be selected as U-dropouts. The luminosity weighted mean dust absorption factor of our sample is 5.4 +/- 0.9$ at 1600Å(abridged). | |
| dc.description | ApJ accepted. 22 pages, 7 figures | |
| dc.identifier | https://arxiv.org/abs/astro-ph/9903054 | |
| dc.identifier | http://arxiv.org/abs/astro-ph/9903054 | |
| dc.identifier | Astrophys.J.521:64,1999 | |
| dc.identifier | doi:10.1086/307523 | |
| dc.identifier.uri | http://salesiana.dossiersoluciones.com/handle/123456789/184821 | |
| dc.subject | Astrophysics | |
| dc.title | Dust Absorption And The Ultraviolet Luminosity Density At z \approx 3 As Calibrated By Local Starburst Galaxies | |
| dc.type | text |