Related papers: Lyman continuum observations across cosmic time: r…
Indirect diagnostics of Lyman continuum (LyC) escape are needed to constrain which sources reionized the universe. We used Mg II to predict the LyC escape fraction (fesc(LyC)) in 14 galaxies selected from the Hobby-Eberly Telescope Dark…
We present the results of rest-frame, UV slitless spectroscopic observations of a sample of 32 z~0.7 Lyman break galaxy (LBG) analogs in the COSMOS field. The spectroscopic search was performed with the Solar Blind Channel (SBC) on Hubble…
Around 400 million years after the Big Bang, the ultraviolet emission from star-forming galaxies reionized the Universe. Ionizing radiation (Lyman Continuum, LyC) is absorbed by cold neutral hydrogen gas (HI) within galaxies, hindering the…
Current data indicate that the reionization of the Universe was complete by redshift z~6-7, and while the sources responsible for this process have yet to be identified, star-forming galaxies are often considered the most likely candidates.…
We present the statistical properties of Ly$\alpha$ emission in 586 galaxies at $z=4.5-14.2$, observed by multiple JWST/NIRSpec spectroscopy projects, including JADES, GLASS, CEERS, and GO/DDT programs. We obtain Ly$\alpha$ equivalent width…
Ly$\alpha$ is the transition to the ground state from the first excited state of hydrogen (the most common element). Resonant scattering of this line by neutral hydrogen greatly impedes its emergence from galaxies, so the fraction of…
$\require{mediawiki-texvc}$Cosmic Reionisation commenced when ultraviolet (UV) radiation produced in the first galaxies began illuminating the cold, neutral gas that filled the primordial Universe. Recent James Webb Space Telescope (JWST)…
We present Lyman continuum (LyC) radiation escape fraction $f_{\rm{esc}}$ measurements for 183 spectroscopically confirmed star-forming galaxies in the redshift range $3.11 < z < 3.53$ in the \textit{Chandra} Deep Field South. We use…
The connection between the escape fraction of ionizing radiation ($f_{esc}$) and the properties of galaxies, such as stellar mass (M*), age, star-formation rate (SFR), and dust content, are key inputs for reionization models, but many of…
To identify the galaxies responsible for the reionization of the Universe, we must rely on the investigation of the Lyman Continuum (LyC) properties of z<5 star-forming galaxies, where we can still directly observe their ionizing radiation.…
$\require{mediawiki-texvc}$Given the sensitivity of the resonant Lyman-$\mathrm{\alpha}$ (Ly$\mathrm{\alpha}$) transition to absorption by neutral hydrogen, observations of Ly$\mathrm{\alpha}$ emitting galaxies (LAEs) have been widely used…
Star forming galaxies are believed to be a major source of Lyman Continuum (LyC) radiation responsible for reionizing the early Universe. Direct observations of escaping ionizing radiation have however been few and with low escape…
Understanding the escape of Lyman continuum (LyC) and Lyman alpha (Lya) photons from molecular clouds is one of the keys to constraining the reionization history of the Universe and the evolution of galaxies at high redshift. Using a set of…
Lyman $\alpha$ emission is highly sensitive to dust and neutral hydrogen and is therefore expected to be strongly suppressed in dusty or gas-rich galaxies during the epoch of reionization (EoR). Nevertheless, numerous moderately dusty…
We report the detection of Lyman continuum (LyC) photons from three massive ($\text{M}_{*}>10^{10}\:\text{M}_{\odot}$) spiral galaxies at a redshift of nearly 1 in the AstroSat UV Deep Field South. Notably, all three systems are viewed at…
[abridged] Among the different observational techniques used to select high-redshift galaxies, the hydrogen recombination line Lyman-alpha (Lya) is of particular interest as it gives access to the measurement of cosmological quantities such…
We study the observed cosmic ionizing background as a constraint on the nature of the sources responsible for the reionization of the Universe. In earlier work, we showed that extrapolations of the Ultra-Violet Luminosity Function (LF) of…
We present six galaxies at z~2 that show evidence of Lyman continuum (LyC) emission based on the newly acquired UV imaging of the Hubble Deep UV legacy survey (HDUV) conducted with the WFC3/UVIS camera on the Hubble Space Telescope (HST).…
We have recently reported the discovery of five low redshift Lyman continuum (LyC) emitters (LCEs, hereafter) with absolute escape fractions fesc(LyC) ranging from 6 to 13%, higher than previously found, and which more than doubles the…
Recent JWST observations of Lyman-$\alpha$ emission at $z \sim 11-6$ indicate a rapid reionization of the intergalactic medium within the first $\sim700$ Myr. The required Lyman continuum (LyC) photon budget may naturally arise from the…