Related papers: CH abundance gradient in TMC-1
OB star clusters originate from parsec-scale massive molecular clumps. We aim to understand the evolution of temperature and density structures on the intermediate-scale ($\lesssim$0.1-1 pc) extended gas of massive clumps. We performed…
We present a comprehensive examination of interstellar P and Cl abundances based on an analysis of archival spectra acquired with the Space Telescope Imaging Spectrograph of the Hubble Space Telescope and the Far Ultraviolet Spectroscopic…
We have determined column densities of H I and/or H_2 for sight lines in the Magellanic Clouds from archival HST and FUSE spectra of H I Lyman-alpha and H_2 Lyman-band absorption. Together with some similar data from the literature, we now…
In previous warm-up chemical models of the low-mass star-forming region L1527, we investigated the evolution of carbon-chain unsaturated hydrocarbon species when the envelope temperature is slightly elevated to $T\approx 30$ K. These models…
We aim to investigate the chemistry and gas phase abundance of HNCO and the variation of the HNCO/CS abundance ratio as a diagnostic of the physics and chemistry in regions of massive star formation. A numerical-chemical model has been…
Molecules that trace the high-density regions of the interstellar medium have been observed in (ultra-)luminous (far-)infrared galaxies, in order to initiate multiple-molecule multiple-transition studies to evaluate the physical and…
Sh 2-29 is a conspicuous star-forming region marked by the presence of massive embedded stars as well as several notable interstellar structures. In this research, our goals were to determine the role of magnetic fields and to study the…
Star formation activity in molecular clouds is often found to be correlated with the amount of material above a column density threshold of $\sim 10^{22} \, {\rm cm^{-2}}$. Attempts to connect this column density threshold to a ${\it…
The recent detection of gas-phase methanol (CH$_3$OH) lines in the disc of TW Hya by Walsh et al. provided the first observational constraints on the complex O-bearing organic content in protoplanetary discs. The emission has a ring-like…
The relative abundances of singly-deuterated methanol isotopologues, [CH$_{2}$DOH]/[CH$_{3}$OD], in star-forming regions deviate from the statistically expected ratio of 3. In Orion KL, the nearest high-mass star-forming region to Earth,…
We report a sensitive search for the rotational transitions of the carbon chain alcohol HC4OH in the frequency range of 21.2-46.7 GHz in the star-forming region L1527 and the dark cloud TMC-1. The motivation was laboratory detection of…
Grain-surface chemistry plays a crucial role in the formation of molecules of astrobiological interest, including H$_{2}$S and complex organic molecules (COMs). They are commonly observed in the gas phase toward star-forming regions, but…
Aims. Our goals are to compare the CS, N2H+ and dust distributions in a representative sample of high-mass star forming dense cores and to determine the physical and chemical properties of these cores. Methods. We compare the results of…
Spectral line survey observations of 7 molecular clouds in the Large Magellanic Cloud (LMC) have been conducted in the 3 mm band with the Mopra 22 m telescope to reveal chemical compositions in low metallicity conditions. Spectral lines of…
UV photochemistry in the surface layers of protoplanetary disks dramatically alters their composition relative to previous stages of star formation. The abundance ratio CN/HCN has long been proposed to trace the UV field in various…
We report the detection of the oxygen-bearing complex organic molecules propenal (C2H3CHO), vinyl alcohol (C2H3OH), methyl formate (HCOOCH3), and dimethyl ether (CH3OCH3) toward the cyanopolyyne peak of the starless core TMC-1. These…
Observations with the Short Wavelength Spectrometer (SWS) onboard the {\it Infrared Space Observatory} (ISO) have led to the first detection of the methyl radical ${\rm CH_3}$ in the interstellar medium. The $\nu_2$ $Q-$branch at 16.5…
We have carried out wide-field (0.17 degree^2) and high-angular resolution (21.3 arcsec ~ 0.04 pc) observations in [CI] line toward the Orion-A giant molecular cloud with the Atacama Submillimeter Telescope Experiment (ASTE) 10 m telescope…
We present CH and CN index analysis and C and N abundance calculations based on the low-resolution blue spectra of red giant branch (RGB) stars in the Galactic globular cluster NGC 7089 (M 2). Our main goal is to investigate the C-N…
This Letter presents a new, remarkably simple diagnostic specifically designed to derive chemical abundances for high redshift galaxies. It uses only the H \alpha, [N II] and [S II] emission lines, which can usually be observed in a single…