Related papers: Molecular Hydrogen Optical Depth Templates for FUS…
We provide new post-COSTAR data on one sightline (Mrk 421) and updated data from another (I Zw 1) from our Hubble Space Telescope (HST) survey of intergalactic Lyman-alpha clouds located along sightlines to four bright quasars passing…
We measure the effect of high column density absorbing systems of neutral hydrogen (HI) on the one-dimensional (1D) Lyman-alpha forest flux power spectrum using cosmological hydrodynamical simulations from the Illustris project. High column…
A detailed study of the absorbing molecular clouds towards the radio source PKS1413+135, at a redshift z=0.247, is reported. Physical conditions are derived for the molecular gas in the frame work of two models: a homogeneous multicomponent…
Molecular hydrogen being unobservable in cold molecular clouds, the column density measurements of molecular gas currently rely either on dust emission observation in the far-IR or on star counting. (Sub-)millimeter observations of numerous…
At visible wavelengths, Venus appears serene and pale-yellow, but since the 1920s, observers have noted high-contrast features in the ultraviolet. These features track the about 4-day superrotation of the upper cloud deck and vary widely…
We report the detection of OH+ and H2O+ in the z=0.89 absorber toward the lensed quasar PKS1830-211. The abundance ratio of OH+ and H2O+ is used to quantify the molecular hydrogen fraction (fH2) and the cosmic-ray ionization rate of atomic…
We report a lambda > 1cm search for rotational molecular absorption towards quasars, now possible with the upgraded Australia Telescope Compact Array (ATCA). The targets were PKS 0201+113, PKS 0336-017 and Q 0537-286, where known damped…
We have performed high-resolution hydrodynamic simulations of the Lyman-alpha forest in a variety of popular cold dark matter dominated cosmologies, including a low density and a vacuum-dominated model. The fluctuation amplitude of these…
We derive total (atomic + molecular) hydrogen densities in giant molecular clouds (GMCs) in the nearby spiral galaxy M33 using a method that views the atomic hydrogen near regions of recent star formation as the product of…
We present a first-principles-based multiscale simulation framework for quantitative predictions of the high-energy part of the Ultraviolet Photoelectron Spectroscopy (UPS) spectra of amorphous molecular solids. The approach combines a…
We show in this paper why molecular millimeter absorption line searches in DLAs have been unsuccessful. We use CO emission line maps of local galaxies to derive the H2 column density distribution function f(N_H2) at z=0. We show that it…
We present the discovery of molecular hydrogen (H_2), including the presence of vibrationally-excited H_2^* in the optical spectrum of the afterglow of GRB 120815A at z=2.36 obtained with X-shooter at the VLT. Simultaneous photometric…
We present a new measurement of the deuterium-to-hydrogen ratio (D/H) in the Lyman limit absorption system at $z = 3.572$ towards Q1937--1009. We use an improved method to measure D/H in QSO absorption systems, which includes extra…
One of the readily accessible observables in trapped cold-atom experiments is the column density, which is determined from optical depth (OD) obtained from absorption imaging and the absorption cross-section ($\sigma_{\rm abs}$). Here we…
Recent experimental results about the formation of molecular hydrogen on astrophysically relevant surfaces under conditions close to those encountered in the interstellar medium are analyzed using rate equations. The parameters of the rate…
A mathematical model is developed to describe column adsorption when the contaminant constitutes a significant amount of the fluid. This requires modelling the variation of pressure and velocity, in addition to the usual…
Context. Neutral atomic hydrogen (HI) absorption lines can be used to probe the cold neutral medium (CNM) at high Galactic latitudes. Cold HI with a significant optical depth from the GASKAP-HI survey is found to be located predominantly if…
We present new theoretical calculations of the line profile of Lyman gamma that include transitions in which a photon is absorbed by a neutral hydrogen atom while it interacts with a proton. Models show that two absorption features located…
A small survey of the UV-absorbing gas in 12 low-$z$ galaxy groups has been conducted using the Cosmic Origins Spectrograph (COS) on-board the Hubble Space Telescope (HST). Targets were selected from a large, homogeneously-selected sample…
Molecular hydrogen absorption in the damped Lyman-alpha system at z = 2.34 towards quasar Q1232+082 is analyzed in order to derive a constraint on a possible temporal variation of the proton-to-electron mass ratio, mu, over cosmological…