THE SPECTRAL EVOLUTION OF THE FIRST GALAXIES. II. SPECTRAL SIGNATURES OF LYMAN CONTINUUM LEAKAGE FROM GALAXIES IN THE REIONIZATION EPOCH

The fraction of ionizing photons that escape (f sub(esc)) from z [gap] 6 galaxies is an important parameter for assessing the role of these objects in the reionization of the universe, but the opacity of the intergalactic medium precludes a direct measurement of f sub(esc) for individual galaxies at...

Full description

Saved in:
Bibliographic Details
Published inThe Astrophysical journal Vol. 777; no. 1; pp. 1 - 12
Main Authors Zackrisson, Erik, Inoue, Akio K, Jensen, Hannes
Format Journal Article
LanguageEnglish
Published United States 01.11.2013
Subjects
ASTRONOMY
ASTROPHYSICS
ASTROPHYSICS, COSMOLOGY AND ASTRONOMY
Continuums
dark ages
first stars
Galactic clusters
GALAXIES
galaxies: high-redshift
GALAXY CLUSTERS
INTERGALACTIC SPACE
IONIZATION
Leakage
LIMITING VALUES
LYMAN LINES
Missions
OPACITY
PHOTONS
RED SHIFT
reionization
Slopes
Spectra
STARS
techniques: spectroscopic
TELESCOPES
UNIVERSE
Online AccessGet full text

Cover

More Information
Summary:The fraction of ionizing photons that escape (f sub(esc)) from z [gap] 6 galaxies is an important parameter for assessing the role of these objects in the reionization of the universe, but the opacity of the intergalactic medium precludes a direct measurement of f sub(esc) for individual galaxies at these epochs. We argue that since f sub(esc) regulates the impact of nebular emission on the spectra of galaxies, it should nonetheless be possible to indirectly probe f sub(esc) well into the reionization epoch. As a first step, we demonstrate that by combining measurements of the rest-frame UV slope beta with the equivalent width of the H beta emission line, galaxies with very high Lyman continuum escape fractions (f sub(esc) [> or =, slanted] 0.5) should be identifiable up to z approximately 9 through spectroscopy with the upcoming James Webb Space Telescope (JWST). By targeting strongly lensed galaxies behind low-redshift galaxy clusters, JWST spectra of sufficiently good quality can be obtained for M sub(1500) [lap] -16.0 galaxies at z approximately 7 and for M sub(1500) [gap] -17.5 galaxies at z approximately 9. Dust-obscured star formation may complicate the analysis, but supporting observations with ALMA or the planned SPICA mission may provide useful constraints on this effect.
Bibliography:ObjectType-Article-1
SourceType-Scholarly Journals-1
ObjectType-Feature-2
content type line 23
ISSN:0004-637X
1538-4357
1538-4357
DOI:10.1088/0004-637X/777/1/39