Related papers: The escape fraction of ionizing photons from high …
We investigate the intrinsic opacity of high-redshift galaxies to outgoing ionising photons using high-quality photometry of a sample of 27 spectroscopically-identified galaxies of redshift 1.9<z<3.5 in the Hubble Deep Field. Our…
We perform joint modeling of the composite rest-frame far-UV (FUV) and optical spectra of redshift 1.85<z<3.49 star-forming galaxies to deduce key properties of the massive stars, ionized ISM, and neutral ISM, with the aim of investigating…
Understanding the sources responsible for reionizing the Universe is a key goal of observational cosmology. A discrepancy has existed between the metagalactic hydrogen ionization rate, Gamma_HI, predicted by early hydrodynamical simulations…
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…
We present indirect constraints on the absolute escape fraction of ionizing photons ($f_{\rm esc}^{\rm LyC}$) of the system GN 42912 which comprises two luminous galaxies ($M_{\rm UV}$ magnitudes of -20.89 and -20.37) at $z\sim7.5$, GN…
We present spectroscopic confirmation of ten highly luminous (L >= 2L*) Lyman alpha emitters in the redshift range 6.01<z<6.49 (nine galaxies and one AGN), initially drawn from a sample of fourteen z_phot >= 6 Lyman break galaxies (LBGs)…
We study the visibility of the Lyman Alpha (Lya) emission line during the Epoch of Reionization (EoR). Combining galactic outflow models with large-scale semi-numeric simulations of reionization, we quantify the probability distribution…
By solving the time-dependent radiation transfer problem of stellar radiation through evolving superbubbles within a smoothly varying HI distribution, we estimate the fraction of ionizing photons emitted by OB associations that escapes the…
The temperature of the low-density intergalactic medium (IGM) at high redshift is sensitive to the timing and nature of hydrogen and HeII reionization, and can be measured from Lyman-alpha forest absorption spectra. Since the memory of…
The Lyman-alpha (Lya) emission line is the primary observational signature of star-forming galaxies at the highest redshifts, and has enabled the compilation of large samples of galaxies with which to study cosmic evolution. The resonant…
The contribution of stars in galaxies to cosmic reionisation depends on the star formation history in the Universe, the abundance of galaxies during reionisation, the escape fraction of ionising photons and the clumping factor of the…
We present improved results of the measurement of the correlation between galaxies and the intergalactic medium (IGM) transmission at the end of reionisation. We have gathered a sample of $13$ spectroscopically confirmed Lyman-break…
Cosmic (hydrogen) reionization marks one of the major phase transitions of the universe at redshift z >= 6. During this epoch, hydrogen atoms in the intergalactic medium (IGM) were ionized by Lyman continuum (LyC) photons. However, it…
The large cross-section of the Lyman alpha (Lya) line makes it a sensitive probe of the ionization state of the intergalactic medium (IGM). Here we present the most complete study to date of the IGM Lya opacity, and its application to the…
We have performed narrow-band imaging observations with the Very Large Telescope, aimed at detecting the Lyman continuum (LC) flux escaping from galaxies at z~3. We do not find any significant LC flux from our sample of two galaxies in the…
We use the spatially-resolved, multi-band photometry in the GOODS South field acquired by the CANDELS project to constrain the nature of candidate Lyman continuum (LyC) emitters at redshift z~3.7 identified using ultra-deep imaging below…
Lyman-alpha (Ly{\alpha}) photons from ionizing sources and cooling radiation undergo a complex resonant scattering process that generates unique spectral signatures in high-redshift galaxies. We present a detailed Ly{\alpha} radiative…
The fluctuations in the emission of redshifted 21cm photons from neutral inter-galactic hydrogen will provide an unprecedented probe of the reionization era. Conventional wisdom assumes that this 21cm signal disappears as soon as…
We study the reionization of the Universe due to haloes that host galaxies undergoing bursts of star formation. By comparing the recent results from the James Webb Space Telescope (JWST) with the cosmological hydrodynamical simulation EAGLE…
A problem still unsolved in cosmology is the identification of the sources of radiation able to reionize HI in the intergalactic medium (IGM) by z~6. Theoretical works and observations seem to indicate that the fraction, f_esc, of HI…