Related papers: Photodesorption of water ice: a molecular dynamics…
Water is usually the main component of ice mantles, which cover the cores of dust grains in cold portions of dense interstellar clouds. When molecular hydrogen is adsorbed onto an icy mantle through physisorption, a common assumption in…
Wavelength dependent photodesorption rates have been determined using synchrotron radiation, for condensed pure and mixed methanol ice in the 7 -- 14 eV range. The VUV photodesorption of intact methanol molecules from pure methanol ices is…
Dust grains in cold circumstellar regions and dark-cloud interiors at 10-20 K are covered by ice mantles. A nonthermal desorption mechanism is invoked to explain the presence of gas-phase molecules in these environments, such as the…
We made near infrared multicolor imaging observations of a disk around Herbig Be star HD100546 using Gemini/NICI. K (2.2\,$\mu$m), H$_2$O ice (3.06\,$\mu$m), and L'(3.8\,$\mu$m) disk images were obtained and we found the 3.1\,$\mu$m…
We present a computational study into the adsorption properties of CO$_2$ on amorphous and crystalline water surfaces under astrophysically relevant conditions. Water and carbon dioxide are two of the most dominant species in the icy…
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…
Processing by interstellar photons affects the composition of the icy mantles on interstellar grains. The rate of photodissociation in solids differs from that of molecules in the gas phase. The aim of this work was to determine an average,…
CO2 ice is one of the most abundant components in ice-coated interstellar ices besides H2O and CO, but the most favorable path to CO2 ice is still unclear. Molecular dynamics calculations on the ultraviolet photodissociation of different…
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…
At low temperatures (10 K), hydrogen atoms can diffuse quickly on grain ice mantles and frequently encounter hydrogen molecules, which cover a notable fraction of grain surface. The desorption energy of H atoms on H2 substrates is much less…
We investigate the effect of photodesorption on the snow line position at the surface of a protoplanetary disk around a Herbig Ae/Be star, motivated by the detection of water ice particles at the surface of the disk around HD142527 by Honda…
Context. Millimetric observations have measured high degrees of molecular deuteration in several species seen around low-mass protostars. The Herschel Space Telescope, launched in 2009, is now providing new measures of the deuterium…
Diffusion of atoms and molecules is a key process for the chemical evolution in the star forming regions of the interstellar medium. Accurate data on the mobility of many important interstellar species is however often not available and…
Interstellar ices are largely composed of frozen water. It is important to derive fundamental parameters for H$_2$O ice such as absorption and scattering opacities for which accurate complex refractive indexes are needed. The primary goal…
Context. Interstellar surface chemistry is a complex process that occurs in icy layers accumulated onto grains of different sizes. Efficiency of surface processes often depends on the immediate environment of adsorbed molecules. Aims. We…
CO$_2$ ice has a phase transition at 35 K when its structure changes from amorphous to crystalline. Using Reflection absorption Infrared Spectroscopy (RAIRS), \"Oberg et al. observed that the photodesorption yield of CO$_2$ ice deposited at…
Currently ~36 different absorption bands have been detected in the infrared spectra of cold, dense interstellar and circumstellar environments. These are attributed to the vibrational transitions of ~17 different molecules frozen on dust…
Core-excitation of water ice releases many different molecules and ions in the gas phase. Studying these desorbed species and the underlying mechanisms can provide useful information on the effects of X-ray irradiation in ice. We report a…
Solid O2 has been proposed as a possible reservoir for oxygen in dense clouds through freeze-out processes. The aim of this work is to characterize quantitatively the physical processes that are involved in the desorption kinetics of CO-O2…
Context. Methane is among the main components of the ice mantles of insterstellar dust grains, where it is at the start of a rich solid-phase chemical network. Quantification of the photon-induced desorption yield of these frozen molecules…