CLASSY VII Ly\alpha\ Profiles: The Structure and Kinematics of Neutral Gas and Implications for LyC Escape in Reionization-Era Analogs

Understand

Lyman-alpha line profiles are a powerful probe of ISM structure, outflow speed, and Lyman continuum escape fraction.

• In this paper, we present the Ly$\alpha$ line profiles of the COS Legacy Archive Spectroscopic SurveY, a sample rich in spectroscopic analogs of reionization-era galaxies.
• A large fraction of the spectra show a complex profile, consisting of a double-peaked Ly$\alpha$ emission profile in the bottom of a damped, Ly$\alpha$ absorption trough.
• Such profiles reveal an inhomogeneous interstellar medium (ISM).