Related papers: Modeling Lyman continuum emission from young galax…
We present results from a new Keck spectroscopic survey of UV-faint LBGs in the redshift range 3<z<7. Combined with earlier Keck and published ESO VLT data, our sample contains more than 600 dropouts, offering new insight into the nature of…
Reionization is an inhomogeneous process, thought to begin in small ionized bubbles of the intergalactic medium (IGM) around overdense regions of galaxies. Recent Lyman-alpha (Ly$\alpha$) studies during the epoch of reionization show…
The escape fraction of Lyman-continuum (LyC) photons ($f_{esc}$) is a key parameter for determining the sources of cosmic reionization at $z\geq 6$. At these redshifts, owing to the opacity of the intergalactic medium, the LyC emission…
We discuss the spectral character of Lyman-limit-selected, star-forming galaxies at z>3. The rest-frame UV spectra of these faint galaxies may show Ly-alpha in either absorption or emission, probably depending upon their local ISM content…
We reconstruct the history of the cosmic star formation in the universe by means of detailed chemical evolution models for galaxies of different morphological types. We consider a picture of coeval, non-interacting evolving galaxies where…
We report the detection of Lyman Continuum (LyC) emission from the galaxy, CDFS-6664, at z=3.797 in a sample of Lyman break galaxies with detected [OIII] emission lines. The LyC emission is detected with a significance ~$5\sigma$ in the…
We perform a spectrophotometric analysis of galaxies at redshifts z = 4 - 6 in cosmological SPH simulations of a Lambda CDM universe. Our models include radiative cooling and heating by a uniform UV background, star formation, supernova…
We present the discovery of a unique Lyman-continuum (LyC) emitter at z=3.088. The LyC emission were detected using the Hubble Space Telescope (HST) WFC3/UVIS F336W filter, covering a rest-frame wavelength range of 760-900 Angstrom. The…
Compact starburst galaxies are thought to include many or most of the galaxies from which substantial Lyman continuum emission can escape into the intergalactic medium. Li and Malkan (2018) used SDSS photometry to find a population of such…
We present a galaxy formation model to understand the evolution of stellar mass (M*) - UV luminosity relations, stellar mass functions and specific star formation rate (sSFR) of Lyman Break Galaxies (LBGs) along with their UV luminosity…
Star-forming galaxies are the sources likely to have reionized the universe. As we cannot observe them directly due to the opacity of the intergalactic medium at $z\gtrsim5$, we study $z\sim3\text{--}5$ galaxies as proxies to place…
We have obtained the first constraints on extended Ly-alpha emission at z ~ 1 in a sample of five radio galaxies. We detect Ly-alpha emission from four of the five galaxies. The Ly-alpha luminosities range from 0.1 - 4 times 10^43 erg/s and…
We combine high resolution hydrodynamical simulations with an intermediate resolution, dark matter only simulation and an analytical model for the growth of ionized regions to estimate the large scale distribution and redshift evolution of…
The LyC escape fraction from galaxies, $f_{\rm esc}$, is strongly boosted by galactic outflows. In the Attenuation-Free Model (AFM) accounting for the properties of $z>10$ galaxies, radiation-driven outflows develop once the galaxy specific…
The timing and duration of the reionization epoch is crucial to the emergence and evolution of structure in the universe. The relative roles that star-forming galaxies, active galactic nuclei and quasars play in contributing to the…
We present results from a survey for z~2.85 Lyman-Continuum (LyC) emission in the HS1549+1933 field and place constraints on the amount of ionizing radiation escaping from star-forming galaxies. Using a custom narrowband filter (NB3420)…
The acquisition of deep Near-IR imaging with Wide Field Camera 3 on the Hubble Space Telescope has provided the opportunity to study the very-high redshift Universe. For galaxies up to $z\approx 7.7$ sufficient wavelength coverage exists to…
We determine the abundance of i'-band drop-outs in the HST/ACS GOODS surveys and the Hubble Ultra Deep Field (UDF). The majority of these sources are likely to be z~6 galaxies whose flux decrement arises from Lyman-alpha absorption. We have…
Reionization is thought to be dominated by low mass galaxies, while direct observations of resolved galaxies probe only the most massive, rarest objects. The cross-correlation between fluctuations in the surface brightness of the cumulative…
We present the results of a photometric redshift analysis designed to identify z>6 galaxies from the near-IR HST imaging in three deep fields (HUDF, HUDF09-2 & ERS). By adopting a rigorous set of criteria for rejecting low-z interlopers,…