2023/10/11 by Liu, Yuchen, Jiang, Linhua, Windhorst, Rogier A. +2 · 1 citation
#Astrophysics of Galaxies (astro-ph.GA) #FOS: Physical sciences
paper · doi:10.48550/arxiv.2310.07283
We present a study of Lyman continuum (LyC) emission in a sample of ∼150 Lyα emitters (LAEs) at z≈3.1 in the Subaru-XMM Deep Survey field. These LAEs were previously selected using the narrowband technique and spectroscopically confirmed with Lyα equivalent widths (EWs) ≥45 Å. We obtain deep UV images using a custom intermediate-band filter U\rm J that covers a wavelength range of 3330 ∼ 3650 Å, corresponding to 810∼890 Å in the rest frame. We detect 5 individual LyC galaxy candidates in the U\rm J band, and their escape fractions (f\rm esc) of LyC photons are roughly between 40% and 80%. This supports a previous finding that a small fraction of galaxies may have very high f\rm esc. We find that the f\rm esc values of the 5 LyC galaxies are not apparently correlated with other galaxy properties such as Lyα luminosity and EW, UV luminosity and slope, and star-formation rate (SFR). This is partly due to the fact that these galaxies only represent a small fraction (∼3%) of our LAE sample. For the remaining LAEs that are not detected in U\rm J, we stack their U\rm J-band images and constrain their average f\rm esc. The upper limit of the average f\rm esc value is about 16%, consistent with the results in the literature. Compared with the non-LyC LAEs, the LyC LAEs tend to have higher Lyα luminosities, Lyα EWs, and SFRs, but their UV continuum slopes are similar to those of other galaxies.