Connecting the escape fraction of Lyman-alpha and Lyman-continuum photons in star-forming galaxies at $\mathbf{z\simeq 4-5}$

Begley, R.
Cullen, F.
McLure, R. J.
Shapley, A. E.
Dunlop, J. S.
Carnall, A. C.
McLeod, D. J.
Donnan, C. T.
Hamadouche, M. L.
Stanton, T. M.

Publication date

November 2023

Language

English

Abstract

We present a study of the connection between the escape fraction of Lyman-alpha (Ly$\alpha$) and Lyman-continuum (LyC) photons within a sample of N=152 star-forming galaxies selected from the VANDELS survey at $3.85<z_{spec}<4.95$. By combining measurements of H$\alpha$ equivalent width $(W_\lambda(\rm{H\alpha}))$ derived from broad-band photometry with Ly$\alpha$ equivalent width $(W_\lambda(Ly\alpha))$ measurements from VANDELS spectra, we individually estimate $f_{\rm{esc}}^{Ly\alpha}$ for our full sample. In agreement with previous studies, we find a positive correlation between $W_\lambda(Ly\alpha)$ and $f_{\rm{esc}}^{Ly\alpha}$, increasing from $f_{\rm{esc}}^{Ly\alpha}\simeq0.04$ at $W_\lambda(Ly\alpha)=10$\r{A} to $f_{\rm{esc}}^{Ly\a...