The Escape of Ly-alpha and Ly-continuum Radiation from Low- and Intermediate-Mass Galaxies
We present our results on calculations of the escape of Ly-alpha and Ly-continuum radiation from low- and intermediate-mass galaxies. Such systems may have played a crucial role in reionization at early times. We use simple analytic models for the underlying galaxy profiles and compare them with semi-analytic and numerical computations of escaping radiation from such systems. We comment on the possible range of values for the critical spectral index of the source radiation at which H and He ionization start to compete, under a variety of physical conditions. Last, we examine data of low- and intermediate-mass galaxy populations in the local volume, including strong-emission line systems like green pea galaxies and Ly-alpha emitting systems, that closely resemble the earliest halos that hosted the first stars. We share a set of observable galaxy properties that could characterize the "leakers", whose high-redshift counterparts would have had significant escape of Ly-alpha and Ly-continuum radiation. This work was supported by the University of San Francisco (USF) Faculty Development Fund, the USF Student Travel Fund, and by the Undergraduate ALFALFA Team through NSF grant AST-1637339.
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NSF-PAR ID:
10168212
Journal Name:
American Astronomical Society meeting
Volume:
235
Page Range or eLocation-ID:
177.03
ISSN:
2152-887X
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