2024/10/12 by Soumil Maulick, Kanak Saha, Maulick, Soumil +3
Engineering · Physics and Astronomy · #Astronomy and Astrophysical Research #Astrophysics of Galaxies (astro-ph.GA) #FOS: Physical sciences #Photocathodes and Microchannel Plates #Space Technology and Applications
paper · pdf · doi:10.48550/arxiv.2410.09515
openalex publication_date 2024/10/12 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
We report the detection of 5 newly identifed Lyman-continuum (LyC) leaker candidates at redshifts 0.99-1.42 in the AstroSat UV Deep Field South F154W image. We derive physical properties of these galaxies using a combination of spectral-energy distribution fitting and information from publicly available spectra. The estimated escape fraction of these objects vary from 14-85% after accounting for the IGM attenuation. With only about a dozen known leakers at these redshifts, these detections significantly raise the fraction of LyC leakers in this redshift range. High-resolution HST UV imaging reveals that a subset of the galaxies in our sample have blue star-forming structures that are likely associated with harder ionizing sources. We find tentative evidence that the LyC emission is spatially offset from the non-ionizing UV continuum centers of these galaxies. The integrated properties of these galaxies, such as the UV continuum slope, dust attenuation, stellar mass, and [O III] λ5007/ [O II] λ3727 ratios, make them atypical compared to known LyC leakers. The leakage of LyC photons from these systems presents a compelling challenge.