Related papers: CF$^+$ excitation in the interstellar medium
We investigated a set of 54 interplanetary coronal mass ejection (ICME) events whose solar sources are very close to the disk center (within 15 degrees from the central meridian). The ICMEs consisted of 23 magnetic cloud (MC) events and 31…
This paper presents a detailed study of excess line broadening in EUV emission lines during the impulsive phase of a C-class solar flare. In this work, which utilizes data from the EUV Imaging Spectrometer (EIS) onboard Hinode, the…
Cross sections are presented for dissociative recombination and electron-impact vibrational excitation of the ArH+ molecular ion at electron energies appropriate for the interstellar environment. The R-matrix method is employed to determine…
(abridged) We present deep spectroscopy of a large sample of low-metallicity emission-line galaxies. The main goal of this study is to derive element abundances in these low-metallicity galaxies. We analyze 121 VLT spectra of HII regions in…
A local turbulence model is developed to study energy cascades in the interstellar medium (ISM) based on self-consistent two-dimensional fluid simulations. The model describes a partially ionized magnetofluid interstellar medium (ISM) that…
Observations towards IRC +10216 of CS, SiO, SiS, NaCl, KCl, AlCl, AlF, and NaCN have been carried out with the IRAM 30-m telescope in the 80-357.5 GHz frequency range. A large number of rotational transitions covering a wide range of energy…
Context: The solution of the nonlocal thermodynamical equilibrium (non-LTE) radiative transfer equation usually relies on stationary iterative methods, which may falsely converge in some cases. Furthermore, these methods are often unable to…
We investigate the non-local thermodynamic equilibrium (NLTE) analysis for \ion{Cu}{1} lines with the updated model atom that includes quantum-mechanical rate coefficients of Cu\,$+$\,H and Cu$^+$\,$+$\,H$^-$ inelastic collisions from the…
CO isotopologue transitions are routinely observed in molecular clouds to probe the column density of the gas, the elemental ratios of carbon and oxygen, and to trace the kinematics of the environment. We aim at estimating the abundances,…
We report new results from quantum calculations of energy-transfer processes taking place in interstellar environments and involving two newly observed molecular species: C$_5$N$^-$ and C$_7$N$^-$ in collision with He atoms and the p-H$_2$…
The H3+ molecular ion plays a fundamental role in interstellar chemistry, as it initiates a network of chemical reactions that produce many interstellar molecules. In dense clouds, the H3+ abundance is understood using a simple chemical…
The boundary conditions of the heliosphere are set by the ionization, density and composition of inflowing interstellar matter. Constraining the properties of the Local Interstellar Cloud (LIC) at the heliosphere requires radiative transfer…
Recent astronomical observations revealed an increasing molecular complexity in the interstellar medium through the detection of a series of large cyclic carbon species. To correctly interpret these detections, a complex analysis is…
We have revisited the chemistry of chlorine-bearing species in the diffuse interstellar medium with new observations of the HCl$^+$ molecular ion and new astrochemical models. Using the GREAT instrument on board SOFIA, we observed the…
Observations of CH$^+$ are used to trace the physical properties of diffuse clouds, but this requires an accurate understanding of the underlying CH$^+$ chemistry. Until this work, the most uncertain reaction in that chemistry was…
We use three-dimensional hydrodynamic numerical simulations to study phase transformations occurring in a clumpy interstellar gas exposed to time-dependent volumetric heating. To mimic conditions in the Galactic interstellar medium, we take…
Despite low elemental abundance of atomic deuterium in interstellar medium (ISM), observational evidences suggest that several species in gas-phase and in ices could be heavily fractionated. We explore various aspects of deuterium…
Non-LTE analysis (LTE is local thermodynamic equilibrium) of the oxygen abundances for 51 Galactic A-, F- and G-type supergiants and bright giants is performed. In contrast with carbon and nitrogen, oxygen does not show any significant…
The reaction between He$^+$ and CH$_3$F forming predominantly CH$_2^+$ and CHF$^+$ has been studied at collision energies $E_{\rm coll}$ between 0 and $k_{\rm B}\cdot 10$~K in a merged-beam apparatus. To avoid heating of the ions by stray…
The photoelectric heating is believed to be the main heating mechanism in cool HI clouds. The heating rate can be estimated through observations of the [CII] line emission, since this is the main coolant in regions where the photoelectric…