Related papers: Chemistry in Protoplanetary Disks: A Sensitivity A…
We investigate the molecular evolution and D/H abundance ratios that develop as star formation proceeds from a dense-cloud core to a protostellar core, by solving a gas-grain reaction network applied to a 1-D radiative hydrodynamic model…
We report high-sensitivity millimetre observations of several molecular species (13CO, HCN, HNC, CN, HCO+ and N2H+) in a sample of compact planetary nebulae. Some species such as HCO+ and CN are particularly abundant compared to envelopes…
Sensitivities of nuclear reaction rates to a variation of nuclear properties are studied. Target nuclei range from proton- to neutron-dripline for 10<=Z<=83. Reactions considered are nucleon- and alpha-induced reactions mediated by the…
The composition of a protoplanetary disk is set by a combination of interstellar inheritance and gas and grain surface chemical reactions within the disk. The survival of inherited molecules, as well as the disk in situ chemistry depends on…
In this paper we review recent progress in our understanding of the chemical evolution of protoplanetary disks. Current observational constraints and theoretical modeling on the chemical composition of gas and dust in these systems are…
Observations of CO+ suggest column densities on the order 10^12 cm^-2 that can not be reproduced by many chemical models. CO+ is more likely to be destroyed than excited in collisions with hydrogen. An anomalous excitation mechanism may…
We explore properties of core-collapse supernova progenitors with respect to the composite uncertainties in the thermonuclear reaction rates by coupling the reaction rate probability density functions provided by the STARLIB reaction rate…
We describe a general yet simple method to analyse the propagation of nuclear reaction rate uncertainties in a stellar nucleosynthesis and mixing context. The method combines post-processing nucleosynthesis and mixing calculations with a…
We calculate the chemical evolution of protoplanetary disks considering radial viscous accretion, vertical turbulent mixing and vertical disk winds. We study the effects on the disk chemical structure when different models for the formation…
The circumnuclear disk (CND) of the Galactic Center is exposed to many energetic phenomena coming from the supermassive black hole Sgr A* and stellar activities. These energetic activities can affect the chemical composition in the CND by…
One of the stumbling blocks for studying the evolution of interstellar molecules is the lack of adequate knowledge of the rate co-efficients of various reactions which take place in the Interstellar medium and molecular clouds. Some of the…
Protoplanetary disks inherit their chemical composition from their natal molecular cloud, but the extent to which this material is preserved versus reset through chemical reprocessing remains an open question. Understanding this balance is…
(Abridged) Protoplanetary disks are vital objects in star and planet formation, possessing all the material which may form a planetary system orbiting the new star. We investigate the synthesis of complex organic molecules (COMs) in disks…
The gas present in planet-forming disks typically exhibits strong emission features of abundant carbon and oxygen molecular carriers. In some instances, protoplanetary disks show an elevated C/O ratio above interstellar values, which leads…
The increasingly large number of complex organic molecules detected in the interstellar medium necessitates robust kinetic models that can be relied upon for investigating the involved chemical processes. Such models require rate constants…
We have carried out model calculations of the photoionized intergalactic medium (IGM) to determine the effects on the predicted ionic column densities due to uncertainties in the published dielectronic recombination (DR) rate coefficients.…
We investigate the evolution of molecular abundance in quiescent protoplanetary disks which are presumed to be around weak-line T Tauri stars. In the region of surface density less than $10^2$ g cm$^{-2}$ (distance from the star $\gtrsim…
The increasing number of observations towards different environments in the Milky Way, as well as theoretical and experimental works, are improving our knowledge of the astrochemical processes in the interstellar medium (ISM). In this…
We present astrochemical photo-dissociation region models in which cosmic ray attenuation has been fully coupled to the chemical evolution of the gas. We model the astrochemical impact of cosmic rays, including those accelerated by…
Despite intensive studies of protoplanetary disks, there is still no reliable way to determine their total mass and their surface density distribution, quantities that are crucial for describing both the structure and the evolution of disks…