2023/12/04 by Alexander Navarre, Navarre, Alexander, Gourav Khullar +23
Physics and Astronomy · #Adaptive optics and wavefront sensing #Astrophysics and Star Formation Studies #Astrophysics of Galaxies (astro-ph.GA) #FOS: Physical sciences #Galaxies: Formation, Evolution, Phenomena
paper · pdf · doi:10.48550/arxiv.2312.02336
openalex publication_date 2023/12/04 · openalex created_date 2023/12/08 · openalex updated_date 2026/07/28
We present six strongly gravitationally lensed Ly-α Emitters (LAEs) at z∼4-5 with HST narrowband imaging isolating Ly-α. Through complex radiative transfer Ly-α encodes information about the spatial distribution and kinematics of the neutral hydrogen upon which it scatters. We investigate the galaxy properties and Ly-α morphologies of our sample. Many previous studies of high-redshift LAEs have been limited in Ly-α spatial resolution. In this work we take advantage of high-resolution Ly-α imaging boosted by lensing magnification, allowing us to probe sub-galactic scales that are otherwise inaccessible at these redshifts. We use broadband imaging from HST (rest-frame UV) and Spitzer (rest-frame optical) in SED fitting; providing estimates on the stellar masses (∼ 108 - 109 M\odot), stellar population ages (t50 <40 Myr), and amounts of dust (AV ∼ 0.1 - 0.6, statistically consistent with zero). We employ non-parametric star-formation histories to probe the young stellar-populations which create Ly-α. We also examine the offsets between the Ly-α and stellar continuum, finding small upper limits of offsets (< 0.1") consistent with studies of low-redshift LAEs; indicating our galaxies are not interacting or merging. Finally, we find a bimodality in our sample's Ly-α morphologies: clumpy and extended. We find a suggestive trend: our LAEs with clumpy Ly-α are generally younger than the LAEs with extended Ly-α, suggesting a possible correlation with age.