Loading...
Please wait, while we are loading the content...
Similar Documents
Direct measurement of dust attenuation in z approx. 1.5 star-forming galaxies from 3d-hst: implications for dust geometry and star formation rates
| Content Provider | NASA Technical Reports Server (NTRS) |
|---|---|
| Author | Kriek, Mariska Price, Sedona H. Franx, Marijn Wuyts, Stijn Conroy, Charlie Brammer, Gabriel B. Rix, Hans-Walter Tease, Katherine Whitaker Momcheva, Ivelina Schreiber, Natascha M. Foerster VanDokkum, Pieter G. Lundren, Britt Nelson, Erica J. Fumagalli, Mattia Skelton, Rosalind E. |
| Copyright Year | 2013 |
| Description | The nature of dust in distant galaxies is not well understood, and until recently few direct dust measurements have been possible. We investigate dust in distant star-forming galaxies using near-infrared grism spectra of the 3D-HST survey combined with archival multi-wavelength photometry. These data allow us to make a direct comparison between dust towards star-forming regions (measured using Balmer decrements) and the integrated dust properties (derived by comparing spectral energy distributions [SEDs] with stellar population and dust models) for a statistically significant sample of distant galaxies. We select a sample of 163 galaxies between 1.36< or = z< or = 1.5 with H(alpha) SNR > or = 5 and measure Balmer decrements from stacked spectra. First, we stack spectra in bins of integrated stellar dust attenuation, and find that there is extra dust extinction towards star-forming regions (AV,HII is 1.81 times the integrated AV, star), though slightly lower than found for low-redshift starburst galaxies. Next, we stack spectra in bins of specific star formation rate (log sSFR), star formation rate (log SFR), and stellar mass (logMâ). We find that on average AV,HII increases with SFR and mass, but decreases with increasing sSFR. The amount of extra extinction also decreases with increasing sSFR and decreasing stellar mass. Our results are consistent with the two-phase dust model - in which galaxies contain both a diffuse and a stellar birth cloud dust component - as the extra extinction will increase once older stars outside the star-forming regions become more dominant. Finally, using our Balmer decrements we derive dust-corrected H(alpha) SFRs, and find evidence that SED fitting produces incorrect SFRs if very rapidly declining SFHs are included in the explored parameter space. Subject headings: dust, extinction- galaxies: evolution- galaxies: high-redshift |
| File Size | 707619 |
| Page Count | 12 |
| File Format | |
| Alternate Webpage(s) | http://archive.org/details/NASA_NTRS_Archive_20140017712 |
| Archival Resource Key | ark:/13960/t21c7066p |
| Language | English |
| Publisher Date | 2013-10-15 |
| Access Restriction | Open |
| Subject Keyword | Direct Dust Measurement Red Shift Galaxies Stellar Mass Starburst Galaxies Extinction Spectral Energy Distribution Balmer Series Stellar Models Photometry Star Formation Rate Ntrs Nasa Technical Reports Server (ntrs) Nasa Technical Reports Server Aerodynamics Aircraft Aerospace Engineering Aerospace Aeronautic Space Science |
| Content Type | Text |
| Resource Type | Article |
