Speaker
Description
Compact low-metallicity starbursts, such as the green pea (GP) galaxies at z~0.1-0.3, are excellent low-redshift analogs of reionization galaxies. The direct detection of Lyman continuum (LyC) emission from GPs observed with HST-COS in the far-UV has opened a new avenue to study the main physical processes governing the escape of ionizing photons from star-forming galaxies and probe indirect diagnostics to identify LyC emitters in the epoch of reionization with the JWST.
In this talk, we will report new results from observational studies on green pea galaxies, including a subset of confirmed LyC emitters from the Low-z Lyman Continuum Survey. We will particularly focus on recent efforts aimed at resolving the complex ionized gas kinematics of GPs from high-dispersion spectroscopy.
Firstly, using VLT/Xshooter and WHT/ISIS high-dispersion spectra we recently found that strong LyC emitters exhibit more complex and broader components in nebular emission lines than galaxies with undetected LyC emission. These results strongly suggest that highly turbulent ISM conditions and prominent ionized gas outflows resulting from massive stars and supernova feedback have a crucial role in the LyC escape.
Secondly, we have conducted the first characterization of the ionized gas outflow properties (mass rate, loading factors, line ratios) of a large sample of GP galaxies with high-resolution integrated spectra. We will show first results that allow comparisons with high-redshift galaxies and predictions from models and simulations.
Finally, we have performed a detailed spatially-resolved, high-dispersion study of reionization analogs. We will show first results that highlight the need for such studies to go one step further and identify the places from which gas turbulence and outflows resulting from strong radiative and mechanical feedback are clearing channels through which LyC photons escape from galaxies.
