Details

Autor(en) / Beteiligte

• Dominguez, A
• SIANA, B
• Henry, A L
• Scarlata, C
• Bedregal, A G
• Malkan, M
• ATEK, H
• Ross, N R
• Colbert, J W
• Teplitz, H I

Titel

DUST EXTINCTION FROM BALMER DECREMENTS OF STAR-FORMING GALAXIES AT 0.75 ⩽ z ⩽ 1.5 WITH HUBBLE SPACE TELESCOPE /WIDE-FIELD-CAMERA 3 SPECTROSCOPY FROM THE WFC3 INFRARED SPECTROSCOPIC PARALLEL SURVEY

Ist Teil von

• The Astrophysical journal, 2013-02, Vol.763 (2), p.1-10

Ort / Verlag

United States

Erscheinungsjahr

2013

Quelle

Electronic Journals Library

Beschreibungen/Notizen

• Spectroscopic observations of H alpha and H beta emission lines of 128 star-forming galaxies in the redshift range 0.75 [< or =, slant] z [< or =, slant] 1.5 are presented. These data were taken with slitless spectroscopy using the G102 and G141 grisms of the Wide-Field-Camera 3 (WFC3) on board the Hubble Space Telescope as part of the WFC3 Infrared Spectroscopic Parallel survey. Interstellar dust extinction is measured from stacked spectra that cover the Balmer decrement (H alpha /H beta ). We present dust extinction as a function of H alpha luminosity (down to 3 x 10 super(41) erg s super(-1)), galaxy stellar mass (reaching 4 x 10 super(8) M sub([middot in circle])), and rest-frame H alpha equivalent width. The faintest galaxies are two times fainter in H alpha luminosity than galaxies previously studied at z ~ 1.5. An evolution is observed where galaxies of the same H alpha luminosity have lower extinction at higher redshifts, whereas no evolution is found within our error bars with stellar mass. The lower H alpha luminosity galaxies in our sample are found to be consistent with no dust extinction. We find an anti-correlation of the [OIII] [lambda]5007/H alpha flux ratio as a function of luminosity where galaxies with L sub(H alpha ) < 5 x 10 super(41) erg s super(-1) are brighter in [OIII] [lambda]5007 than H alpha . This trend is evident even after extinction correction, suggesting that the increased [OIII] [lambda]5007/H alpha ratio in low-luminosity galaxies is likely due to lower metallicity and/or higher ionization parameters.