We present deep spectroscopy of 17 very low mass (M* ~ 2.0x10^6 Msun to
1.4x10^9 Msun) and low luminosity (M_UV ~ -13.7 to -19.9) gravitationally
lensed galaxies in the redshift range z~1.5-3.0. Deep rest-frame ultraviolet
spectra reveal large equivalent width emission from numerous lines (NIV,
OIII, CIV, Si III, CIII) which are rarely seen in individual spectra of more
massive star forming galaxies. CIII is detected in 16 of 17 low mass star
forming systems with rest-frame equivalent widths as large as 13.5 Angstroms.
Nebular CIV emission is present in the most extreme CIII emitters, requiring
an ionizing source capable of producing a substantial component of photons with
energies in excess of 47.9 eV. Photoionization models support a picture whereby
the large equivalent widths are driven by the increased electron temperature
and enhanced ionizing output arising from metal poor gas and stars, young
stellar populations, and large ionization parameters. The young ages implied by
the emission lines and continuum SEDs indicate that the extreme line emitters
in our sample are in the midst of a significant upturn in their star formation
activity. The low stellar masses, blue UV colors, and large sSFRs of our sample
are similar to those of typical z>6 galaxies. Given the strong attenuation of
Ly-alpha in z>6 galaxies we suggest that CIII is likely to provide our best
probe of early star forming galaxies with ground-based spectrographs and one of
the most efficient means of confirming z>10 galaxies with the James Webb Space
Telescope.
Description
[1408.1420] Ultraviolet Emission Lines in Young Low Mass Galaxies at z~2: Physical Properties and Implications for Studies at z>7
%0 Generic
%1 stark2014ultraviolet
%A Stark, Daniel P.
%A Richard, Johan
%A Siana, Brian
%A Charlot, Stephane
%A Freeman, William R.
%A Gutkin, Julia
%A Wofford, Aida
%A Robertson, Brant
%A Amanullah, Rahman
%A Watson, Darach
%A Milvang-Jensen, Bo
%D 2014
%K galaxy hard highz photoionisation spectra
%T Ultraviolet Emission Lines in Young Low Mass Galaxies at z~2: Physical
Properties and Implications for Studies at z>7
%U http://arxiv.org/abs/1408.1420
%X We present deep spectroscopy of 17 very low mass (M* ~ 2.0x10^6 Msun to
1.4x10^9 Msun) and low luminosity (M_UV ~ -13.7 to -19.9) gravitationally
lensed galaxies in the redshift range z~1.5-3.0. Deep rest-frame ultraviolet
spectra reveal large equivalent width emission from numerous lines (NIV,
OIII, CIV, Si III, CIII) which are rarely seen in individual spectra of more
massive star forming galaxies. CIII is detected in 16 of 17 low mass star
forming systems with rest-frame equivalent widths as large as 13.5 Angstroms.
Nebular CIV emission is present in the most extreme CIII emitters, requiring
an ionizing source capable of producing a substantial component of photons with
energies in excess of 47.9 eV. Photoionization models support a picture whereby
the large equivalent widths are driven by the increased electron temperature
and enhanced ionizing output arising from metal poor gas and stars, young
stellar populations, and large ionization parameters. The young ages implied by
the emission lines and continuum SEDs indicate that the extreme line emitters
in our sample are in the midst of a significant upturn in their star formation
activity. The low stellar masses, blue UV colors, and large sSFRs of our sample
are similar to those of typical z>6 galaxies. Given the strong attenuation of
Ly-alpha in z>6 galaxies we suggest that CIII is likely to provide our best
probe of early star forming galaxies with ground-based spectrographs and one of
the most efficient means of confirming z>10 galaxies with the James Webb Space
Telescope.
@misc{stark2014ultraviolet,
abstract = {We present deep spectroscopy of 17 very low mass (M* ~ 2.0x10^6 Msun to
1.4x10^9 Msun) and low luminosity (M_UV ~ -13.7 to -19.9) gravitationally
lensed galaxies in the redshift range z~1.5-3.0. Deep rest-frame ultraviolet
spectra reveal large equivalent width emission from numerous lines (NIV],
OIII], CIV, Si III], CIII]) which are rarely seen in individual spectra of more
massive star forming galaxies. CIII] is detected in 16 of 17 low mass star
forming systems with rest-frame equivalent widths as large as 13.5 Angstroms.
Nebular CIV emission is present in the most extreme CIII] emitters, requiring
an ionizing source capable of producing a substantial component of photons with
energies in excess of 47.9 eV. Photoionization models support a picture whereby
the large equivalent widths are driven by the increased electron temperature
and enhanced ionizing output arising from metal poor gas and stars, young
stellar populations, and large ionization parameters. The young ages implied by
the emission lines and continuum SEDs indicate that the extreme line emitters
in our sample are in the midst of a significant upturn in their star formation
activity. The low stellar masses, blue UV colors, and large sSFRs of our sample
are similar to those of typical z>6 galaxies. Given the strong attenuation of
Ly-alpha in z>6 galaxies we suggest that CIII] is likely to provide our best
probe of early star forming galaxies with ground-based spectrographs and one of
the most efficient means of confirming z>10 galaxies with the James Webb Space
Telescope.},
added-at = {2014-08-08T09:43:08.000+0200},
author = {Stark, Daniel P. and Richard, Johan and Siana, Brian and Charlot, Stephane and Freeman, William R. and Gutkin, Julia and Wofford, Aida and Robertson, Brant and Amanullah, Rahman and Watson, Darach and Milvang-Jensen, Bo},
biburl = {https://www.bibsonomy.org/bibtex/2812a218b404075bd8a05935e32f745bb/miki},
description = {[1408.1420] Ultraviolet Emission Lines in Young Low Mass Galaxies at z~2: Physical Properties and Implications for Studies at z>7},
interhash = {b8e433effac11b74a245285ae3f093d4},
intrahash = {812a218b404075bd8a05935e32f745bb},
keywords = {galaxy hard highz photoionisation spectra},
note = {cite arxiv:1408.1420Comment: 22 pages, 8 figures, accepted for publication in MNRAS},
timestamp = {2014-08-08T09:43:08.000+0200},
title = {Ultraviolet Emission Lines in Young Low Mass Galaxies at z~2: Physical
Properties and Implications for Studies at z>7},
url = {http://arxiv.org/abs/1408.1420},
year = 2014
}