相关论文: Acetaldehyde binding energies: a coupled experimen…
Hydrogenation reactions of CO in inter- and circumstellar ices are regarded as an important starting point in the formation of more complex species. Previous laboratory measurements by two groups on the hydrogenation of CO ices resulted in…
The evolution of star-forming regions and their thermal balance are strongly influenced by their chemical composition, that, in turn, is determined by the physico-chemical processes that govern the transition between the gas phase and the…
The morphology of water ice in the interstellar medium is still an open question. Although accretion of gaseous water could not be the only possible origin of the observed icy mantles covering dust grains in cold molecular clouds, it is…
During the evolution of diffuse clouds to molecular clouds, gas-phase molecules freeze out on surfaces of small dust particles to form ices. On dust surfaces, water is the main constituent of the icy mantle in which a complex chemistry is…
Using the King & Wells method, we present experimental data on the dependence of the sticking of molecular hydrogen and deuterium on the beam temperature onto non- porous amorphous solid water (ASW) ice surfaces of interstellar interest. A…
We present Giant Meterwave Radio Telescope images of the 1065 MHz emission from the 1_11 -> 1_10 rotational transition of acetaldehyde (CH3CHO) in the molecular cloud complex Sgr B2. Our observations are unique in that they have a high…
Metal-bearing species in diffuse or molecular clouds are often overlooked in astrochemical modeling except for the charge exchange process. However, catalytic cycles involving these metals can affect the abundance of other compounds. We…
The interstellar medium is known to be chemically complex. Organic molecules with up to 11 atoms have been detected in the interstellar medium, and are believed to be formed on the ices around dust grains. The ices can be released into the…
Ice desorption affects the evolution of the gas-phase chemistry during the protostellar stage, and also determines the chemical composition of comets forming in circumstellar disks. From observations, most volatile species are found in…
Accurate measurements of interstellar deuterium abundances along lines of sight extending out to several hundred parsecs by FUSE and other instruments is making D/H a useful tool for understanding Galactic chemical evolution. We find that…
[abridged] The enhanced degrees of deuterium fractionation observed in envelopes around protostars demonstrate the importance of chemistry at low temperatures, relevant in pre- and protostellar cores. formaldehyde is an important species in…
We investigated the behavior of H$_2$, main constituent of the gas phase in dense clouds, after collision with amorphous solid water (ASW) surfaces, one of the most abundant chemical species of interstellar ices. We developed a general…
Methanol is the most complex molecule securely identified in interstellar ices and is a key chemical species for understanding chemical complexity in astrophysical environments. Important aspects of the methanol ice photochemistry are still…
Extremely high deuteration of several molecules have been observed around low mass protostars since a decade. Among them, formaldehyde and methanol present particularly high deuteration, with observations of abundant doubly and triply…
Many molecules observed in the interstellar medium are thought to result from thermal desorption of ices. Parameters such as desorption energy and pre-exponential frequency factor are essential to describe the desorption of molecules.…
The relative column densities of the structural isomers methyl formate, glycolaldehyde, and acetic acid are derived for a dozen positions towards the massive star-forming regions MM1 and MM2 in the NGC 6334I complex, which are separated by…
A model is proposed for the formation of water ice mantles on grains in interstellar clouds. This occurs by direct accretion of monomers from the gas, be they formed by gas or surface reactions. The model predicts the existence of a…
Reactions involving atomic carbon in its ground electronic state, C(3P), play an important role in astrochemistry due to high C-atom abundance levels. Here we performed a kinetic investigation of the reaction between C(3P) and acetaldehyde,…
Dimethyl ether is one of the most abundant interstellar complex organic molecules. Yet its formation route remains elusive. In this work, we have performed electronic structure and kinetics calculations to derive the rate coefficients for…
An increasing number of large molecules have been positively identified in space. Many of these molecules are of biological interest and thus provide insight into prebiotic organic chemistry in the protoplanetary nebula. Among these…