Related papers: Atomic hydrogen in AGB circumstellar environments.…

We present observations of pure rotational molecular hydrogen emission from the Herbig Ae star, AB Aurigae. Our observations were made using the Texas Echelon Cross Echelle Spectrograph (TEXES) at the NASA Infrared Telescope Facility and…

We present medium resolution near infrared spectroscopic observations of 41 obscured and intermediate class AGN (type 2, 1.9 and 1.8; AGN2) with redshift $z \lesssim$0.1, selected from the Swift/BAT 70-month catalogue. The observations have…

Y CVn is a carbon star surrounded by a detached dust shell that has been imaged by the Infrared Space Observatory at 90 microns. With the Nancay Radio Telescope we have studied the gaseous counterpart in the 21-cm HI emission line. New data…

We have observed the HI distribution in an area 40' x 40' around the neutron star candidate RX J0822-4300, which is located in the supernova remnant Puppis A. The observations of the 21 cm line were obtained with the Australia Telescope…

This work aims to measure the mass accretion rate, the accretion luminosity, and more generally the physical conditions of the warm emitting gas in the inner disk of the very low-mass star 2MASS-J16053215-1933159. We investigate the source…

The atomic phase of the interstellar medium plays a key role in the formation process of molecular clouds. Due to the line-of-sight confusion in the Galactic plane that is associated with its ubiquity, atomic hydrogen emission has been…

We report the discovery of three HI absorbers toward low-power radio active galactic nuclei (AGNs) in a pilot HI absorption survey with the Five-hundred-meter Aperture Spherical radio Telescope (FAST). Compared to past studies, FAST…

Absorbers in the spectrum of background objects probe the circumgalactic medium (CGM) surrounding galaxies, but its physical properties remain unconstrained. We use the cosmological hydrodynamical simulation TNG50 to statistically trace the…

There is a robust polyatomic chemistry in diffuse, partially-molecular interstellar gas that is readily accessible in absorption at radio/mm/sub-mm wavelengths. Accurate column densities are derived owing to the weak internal excitation, so…

Spectroscopic observations of AH Herculis during a deep quiescent state are put forward. We found the object in a rare long minima, allowing us to derive accurately the semi-amplitudes: $K_1 =121 \pm \, 4$ \kms\ and $K_2 =152 \pm 2$ \kms\…

Absorption features from the Lyman and Werner bands of interstellar molecular hydrogen were recorded by the Interstellar Medium Absorption Profile Spectrograph (IMAPS) at a wavelength resolving power R=80,000 in the spectra of delta Ori and…

We present an HI 21cm absorption study of a sample of 26 radio-loud active galactic nuclei (AGN) at $0.25 < z < 0.4$ carried out with the Karl G. Jansky Very Large Array. Our aim was to study the rate of incidence of HI in various classes…

A spectral scan of the circumstellar environment of the asymptotic giant branch (AGB) star R~Doradus was taken with ALMA in cycle 2 at frequencies between 335 and 362 GHz and with a spatial resolution of $\sim$150 milliarcseconds. Many…

The nebular circumstellar environments of cool evolved stars are known to harbour a rich morphological complexity of gaseous structures on different length scales. A large part of these density structures are thought to be brought about by…

We have complemented existing observations of HI absorption with new observations of HCO$^+$, C$_2$H, HCN, and HNC absorption from the Atacama Large Millimeter/submillimeter Array (ALMA) and the Northern Extended Millimeter Array (NOEMA) in…

Using adaptive optics on Keck and the VLT in the H- and K-bands, we have begun a project to probe the dynamics and star formation around AGN on scales of 0.1arcsec. The stellar content of the nucleus is traced through the 2.29micron CO2-0…

Atomic Hydrogen (HI) is a useful tracer of gas in and around galaxies, and can be found in extended disk-like structures well beyond a system's optical extent. Here we investigate the properties of extended HI disks that emerge in six Milky…

The main aim is to derive reliable mass-loss rates and circumstellar SiO abundances for a sample of 40 S-type AGB stars based on new multi-transitional CO and SiO radio line observations. In addition, the results are compared to previous…

Neutral hydrogen 21 cm transition is a useful tracer of the neutral interstellar medium. However, inferring physical condition from the observed 21 cm absorption and/or emission spectra is often not straightforward. One complication in…

We use observations from the Giant Metrewave Radio Telescope (GMRT) to measure the atomic hydrogen gas content of star-forming galaxies at z = 0.24 (i.e. a look-backtime of ~3 Gyr). The sample of galaxies studied were selected from…