相关论文: Radiative transfer effects in primordial hydrogen …
Complex radiative transfer (RT) of the Lyman-$\alpha$ photons poses a theoretical challenge to galaxy surveys which infer the large-scale structure with Lyman-$\alpha$ emitters (LAEs). Guided by RT simulations, prior studies investigated…
One of the most sought-after signatures of reionization is a rapid increase in the ionizing background (usually measured through the Lyman-alpha optical depth toward distant quasars). Conventional wisdom associates this with the "overlap"…
[abridged] Aims. The aim of this paper is to assess the impact of the interstellar medium (ISM) physics on Lyman-alpha (Lya) radiation transfer and to quantify how galaxy orientation with respect to the line of sight alters observational…
The Ly$\alpha$ emission line is one of the most promising probes of cosmic reionisation but isolating the signature of a change in the ionisation state of the IGM is challenging because of intrinsic evolution and internal radiation transfer…
The hydrogen Lyman-alpha plays a dominant role in the radiative energy transport in the lower transition region, and is important for the stud- ies of transition-region structure as well as solar wind origin. We investigate the Ly-alpha…
The forest of Lyman-alpha absorption lines seen in the spectra of distant quasars has become an important probe of the distribution of matter in the Universe. We use large, hydrodynamical simulations from the OWLS project to investigate the…
Lyman-alpha forest lines in QSO spectra have typical widths of 20-50 km/s. Low column density absorbers in cosmological simulations are large, diffuse structures, and the Hubble flow across the spatially extended absorber is usually the…
The first, self-consistent calculations are presented of the cosmological, H2-dissociating UV background produced during the epoch of reionization by the sources of reionization. Large-scale radiative transfer simulations of reionization…
Mapping the intergalactic medium (IGM) in Lyman-$\alpha$ emission would yield unprecedented tomographic information on the large-scale distribution of baryons and potentially provide new constraints on the UV background and various feedback…
We present a low energy expansion of the Kramers-Heisenberg formula for atomic hydrogen in terms of $(\omega/\omega_l)$, where $\omega_l$ and $\omega$ are the angular frequencies corresponding to the Lyman limit and the incident radiation,…
Photons emitted during the formation of primordial hydrogen and helium atoms over the Epoch of Recombination are expected to be preserved as additive distortions to the Cosmic Microwave Background (CMB) spectrum. The 'ripple' like spectral…
The inhibition of the total HI $n\leftrightarrow 1$ transition rate by delayed resonant reabsorption of HI $(n+1)\to 1$ photons by HI $n\to 1$ line which is possible due to cosmological redshift is considered semi-analytically. The method…
Lyman-$\alpha$ (Ly$\alpha$) emitting galaxies are powerful tools to probe the late stages of cosmic reionization. The observed sudden drop in Ly$\alpha$ fraction at $z>6$ is often interpreted as a sign of reionization, since the…
The global 21-cm signal from the cosmic dawn is affected by a variety of heating and cooling processes. We investigate the impact of heating due to Lyman-$\alpha$ (Ly~$\alpha$) photons on the global 21-cm signal at cosmic dawn using an…
We present new calculations of unified line profiles for hydrogen perturbed by collisions with protons. We report on new calculations of the potential energies and dipole moments which allow the evaluation of profiles for the lines of the…
The physical ingredients to describe the epoch of cosmological recombination are amazingly simple and well-understood. This fact allows us to take into account a very large variety of processes, still finding potentially measurable…
Rayleigh scattering of the cosmic microwave background (CMB) by neutral hydrogen shortly after recombination leaves frequency-dependent imprints on intensity and polarization fluctuations. High signal-to-noise observations of CMB Rayleigh…
We evaluate the effect of variations in the electron-impact excitation cross sections on the non-LTE line formation for hydrogen in early-type stars. While the Balmer lines are basically unaffected by the choice of atomic data, the Brackett…
Line Intensity Mapping (LIM) has garnered attention as a powerful cosmological probe, with next-generation instruments such as SPHEREx preparing to map the evolution of large-scale structure during the Epoch of Reionization (EoR).…
Hydrogen Ly-alpha is our primary emission-line window into high redshift galaxies. Surprisingly, despite an extensive literature, Ly-alpha radiative transfer in the most realistic case of a dusty, multi-phase medium has not received…