Related papers: Molecular lines in absorption: recent results

Stellar emission and absorption lines are routinely observed in galaxies at redshifts up to 5 with spectrographs on 8-10m class telescopes. While the overall spectra are well understood and have been successfully modeled using empirical and…

Absorption spectroscopy toward high-redshift quasars provides strong constraints on the putative variation of fundamental constants of physics on cosmological time scales. The submillimeter ground-state transitions of methylidyne (CH) and…

Based upon QSO absorption line studies, galaxies at 0.3 < z < 1.0 are seen to have extended gaseous "halos". When the absorption lines are observed at high resolution, the velocity distribution of the absorbing gas gives clues as to where…

This white paper emphasizes the potential of QSO absorption lines in the rest-frame far/extreme UV at rest-frame wavelengths from ~500 to 2000 A. In this wavelength range, species such as Ne VIII, Na IX, and Mg X can be detected, providing…

Spinning dust grains in front of the bright Galactic synchrotron background can produce a weak absorption signal that could affect measurements of high redshift 21 cm absorption. At frequencies near 80 MHz where the EDGES experiment has…

We detected with the IRAM interferometer the lines of CO(4-3) and CO(9-8) from the recently-discovered broad absorption line quasar APM 08279+5255. The molecular lines are at a redshift of 3.911, which we take to be the true cosmological…

We present the methodology for ``blind'' millimetre-wave surveys for redshifted molecular absorption in the CO/HCO$^+$ rotational lines. The frequency range $30-50$ GHz appears optimal for such surveys, providing sensitivity to absorbers at…

This paper presents data from the BIMA interferometer showing spatially resolved absorption spectra of the gravitationally lensed quasar PKS 1830-211. High-resolution (1.2 km/s) spectra were taken in two spectral windows centered on the…

We obtained over 90 hours of spectroscopic observations of four exoplanetary systems with the Hobby-Eberly Telescope (HET). Observations were taken in transit and out of transit, and we analyzed the differenced spectra---i.e., the…

A new molecular hydrogen cloud has been identified at z = 3.025 in the absorption-line spectrum of the quasar 0347-3819 observed with the UVES spectrograph at the VLT/Kueyen telescope. At the same redshift numerous metal lines and the DI…

Recent observations and theoretical calculations suggest that some QSO absorption line systems may be due to gas in small dark matter halos with circular velocities on the order of 30 km/s. Additional observational evidence suggests that,…

Magnitude-limited galaxy redshift surveys are now providing large samples of galaxies to beyond z=2, while color-selected and emission-line-selected samples are finding galaxies to z=4.7. A broad picture is emerging of galaxy formation…

A statistical analysis of the space-time distribution of absorption-line systems (ALSs) observed in QSO spectra within the cosmological redshift interval $z$=0.0--3.7 is carried out on the base of our catalog of absorption systems…

We have recently completed the analysis of a survey of the HI line in emission/absorption against 79 radio sources. Our CNM temperatures are about half those of previous authors and we find a substantial quantity of thermally unstable WNM.…

This review summarizes recent studies of the cold neutral hydrogen gas associated with galaxies probed via the HI 21-cm absorption line. HI 21-cm absorption against background radio-loud quasars is a powerful tool to study the neutral gas…

Little red dots (LRDs) are an abundant population of compact high-redshift sources with red rest-frame optical continua, discovered by the James Webb Space Telescope (JWST). Their red colors and power sources have been attributed either to…

We report a tentative detection with the IRAM 30m telescope of the LiH molecule in absorption in front of the lensed quasar B0218+357. We have searched for the J = 0 -- 1 rotational line of lithium hydride at 444 GHz (redshifted to 263…

Previous surveys for HI 21-cm absorption in z > 0.1 radio galaxies and quasars yield a 40% detection rate, which is attributed to unified schemes of active galactic nuclei (AGN). In this paradigm absorption is only witnessed in (close to)…

We present the detection and analysis of H2 absorption at z = 4.24 towards the bright quasar J0007-5705, observed with the Very Large Telescope as part of the ESPRESSO QUasar Absorption Line Survey (EQUALS). The high resolving power,…

We present the first detection of carbon radio recombination line absorption along the line of sight to Cygnus A. The observations were carried out with the LOw Frequency ARray in the 33 to 57 MHz range. These low frequency radio…