English
Related papers

Related papers: Hydrocarbon anions in interstellar clouds and circ…

200 papers

Little is known about the chemistry of isocyanates (compounds with the functional group R-N=C=O) in the interstellar medium, as only four of them have been detected so far: isocyanate radical (NCO), isocyanic acid (HNCO), N-protonated…

We have developed a model for molecular hydrogen formation under astrophysically relevant conditions. This model takes fully into account the presence of both physisorbed and chemisorbed sites on the surface, allows quantum mechanical…

Astrophysics · Physics 2009-11-07 S. Cazaux , A. G. G. M. Tielens

The sheer interstellar abundance of helium makes any bound molecules or complexes containing it of potential interest for astrophysical observation. This work utilizes high-level and trusted quantum chemical techniques to predict the…

Space Physics · Physics 2017-11-10 Cody J. Stephan , Ryan C. Fortenberry

We report the detection of hydrogen chloride, HCl, in diffuse molecular clouds on the line of sight towards the star-forming region W31C (G10.6-0.4). The J = 1-0 lines of the two stable HCl isotopologues, H35Cl and H37Cl, are observed using…

Astrophysics of Galaxies · Physics 2016-11-04 R. R. Monje , D. C. Lis , E. Roueff , M. Gerin , M. De Luca , D. A. Neufeld , B. Godard , T. G. Phillips

We report the first interstellar detection of DC$_7$N and six $^{13}$C-bearing isotopologues of HC$_7$N toward the dark cloud TMC-1 through observations with the Green Bank Telescope, and confirm the recent detection of HC$_5$$^{15}$N. For…

We present a millimetre molecular line survey of seven high mass loss rate carbon stars in both the northern and southern skies. A total of 196 emission lines (47 transitions) from 24 molecular species were detected. The observed CO…

Astrophysics · Physics 2009-11-07 P. M. Woods , F. L. Schoeier , L. -A. Nyman , H. Olofsson

Comets have similar compositions to interstellar medium ices, suggesting at least some of their molecules maybe inherited from an earlier stage of evolution. To investigate the degree to which this might have occurred we compare the…

Earth and Planetary Astrophysics · Physics 2025-09-26 Karen Willacy , Liton Majumdar , Boncho Bonev , Erika Gibb , Neil Dello Russo , Michael DiSanti , Ronald J. Vervack , Nathan X Roth

Infrared spectroscopic observations have established the presence of hydrocarbon ices on Pluto and other TNOs, but the abundances of such molecules cannot be deduced without accurate optical constants (n, k) and reference spectra. In this…

Instrumentation and Methods for Astrophysics · Physics 2015-02-10 R. L. Hudson , P. A. Gerakines , M. H. Moore

C$_2$H is one of the first radicals to be detected in the interstellar medium. Its higher rotational transitions have recently become available with the Herschel Space Observatory. We aim to constrain the physical parameters of the C$_2$H…

Astrophysics of Galaxies · Physics 2015-06-17 Z. Nagy , V. Ossenkopf , F. F. S. Van der Tak , A. Faure , Z. Makai , E. A. Bergin

Chlorine and molecular hydrogen are known to be tightly linked together in the cold phase of the local interstellar medium through rapid chemical reactions. We present here the first systematic study of this relation at high redshifts using…

Astrophysics of Galaxies · Physics 2015-06-23 S. A. Balashev , P. Noterdaeme , V. V. Klimenko , P. Petitjean , R. Srianand , C. Ledoux , A. V. Ivanchik , D. A. Varshalovich

We report here the first detection in the interstellar medium of the cyanomidyl radical (HNCN). Using the Yebes 40m and the IRAM 30m telescopes, we have targeted the doublets of the $N$=2$-$1, 4$-$3, 5$-$4, 6$-$5, and 7$-$6 transitions of…

Observations of chemical species can provide an insight into the physical conditions of the emitting gas but it is important to understand how their abundances and excitation vary within different heating environments. C$_2$H is a molecule…

We present column density measurements of the HD molecule in the interstellar gas toward 17 Galactic stars. The values for the seven most heavily reddened sightlines, with E(B-V) = 0.38-0.72, are derived from observations with the Far…

We determined oxygen and iron abundances of the interstellar medium (ISM) using K-shell (O) and L-shell (Fe) X-ray photo-ionization edges towards Ultra luminous X-ray sources (ULXs). We determine the hydrogen column densities (n_H) towards…

Astrophysics · Physics 2007-05-23 Lisa M. Winter , Richard F. Mushotzky , Christopher S. Reynolds

(Abridged) Near- to mid-IR observations of protoplanetary disks show that the inner regions (<10AU) are rich in small organic volatiles (e.g., C2H2 and HCN). Trends in the data suggest that disks around cooler stars (~3000K) are potentially…

Earth and Planetary Astrophysics · Physics 2016-08-08 Catherine Walsh , Hideko Nomura , Ewine F. van Dishoeck

It is a fact that interstellar formation processes are thermodynamically affected. Based on this, the seven heterocycles; imidazole, pyridine, pyrimidine, pyrrole, quinoline, isoquinoline and furan that have been searched for from different…

Astrophysics of Galaxies · Physics 2021-09-08 Emmanuel E. Etim , ROA Adelagun , Chrysanthus Andrew , Oladimeji Enock Oluwole

Polycyclic aromatic hydrocarbons (PAHs) are among the most ubiquitous compounds in the universe, accounting for up to ~25% of all interstellar carbon. Since most unsubstituted PAHs do not possess permanent dipole moments, they are invisible…

Mid-infrared spectral observations Uranus acquired with the Infrared Spectrometer (IRS) on the Spitzer Space Telescope are used to determine the abundances of C2H2, C2H6, CH3C2H, C4H2, CO2, and tentatively CH3 on Uranus at the time of the…

Infrared (IR) absorption spectra of individual polycyclic aromatic hydrocarbons (PAHs) containing methyl (-CH3), methylene (>CH2), or diamond-like *CH groups and IR spectra of mixtures of methylated and hydrogenated PAHs prepared by gas…

The results of experiments on the formation of molecular hydrogen on low density and high density amorphous ice surfaces are analyzed using a rate equation model. The activation energy barriers for the relevant diffusion and desorption…