Related papers: Hydrogen isotope exchanges between water and metha…
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…
We investigate water and deuterated water chemistry in turbulent protoplanetary disks. Chemical rate equations are solved with the diffusion term, mimicking turbulent mixing in vertical direction. Water near the midplane is transported to…
Ethanol (CH3CH2OH) has been detected in interstellar ices within regions associated with the early stages of star and planet formation. Its solid-phase pathways can lead to diverse conditions that can significantly influence its…
Context: Despite the low elemental deuterium abundance in the Galaxy, enhanced molecular D/H ratios have been found in the environments of low-mass star-forming regions and, in particular, the Class 0 protostar IRAS 16293-2422. Aims: The…
Gas-phase and solid-state chemistry in low-temperature interstellar clouds and cores leads to a D/H enhancement in interstellar ices, which is eventually inherited by comets, meteorites, and even planetary satellites. Hence, the D/ H ratio…
Context: Methanol is thought to be mainly formed during the prestellar phase and its deuterated form keeps memory of the conditions at that epoch. Thanks to the unique combination of high angular resolution and sensitivity provided by ALMA,…
Deuteration is a crucial tool to understand the complexity of interstellar chemical processes, especially when they involve the interplay of gas-phase and grain-surface chemistry. In the case of multiple deuteration, comparing observation…
Context. The molecular composition of interstellar ice mantles is defined by gas-grain processes in molecular clouds, with the main components being $H_2O$, $CO$, and $CO_2$. $CH_3OH$ ice is detected towards the denser regions, where large…
Clouds of high infrared extinction are promising sites of massive star/cluster formation. A large number of cloud cores discovered in recent years allows investigation of possible evolutionary sequence among cores in early phases. We have…
In the centre of pre-stellar cores, deuterium fractionation is enhanced due to the low temperatures and high densities. Therefore, the chemistry of deuterated molecules can be used to study the earliest stages of star formation. We analyse…
Regolith on Mars exchanges water with the atmosphere on a diurnal basis and this process causes significant variation in the abundance of water vapor at the surface. While previous studies of regolith-atmosphere exchange focus on the…
Context. Interstellar ice is the main form of metal species in dark molecular clouds. Experiments and observations have shown that the ice is significantly processed after the freeze-out of molecules onto grains. The processing is caused by…
We report the detection of D2CO in a sample of starless dense cores, in which we previously measured the degree of CO depletion. The deuterium fractionation is found extremely high, [D2CO]/[H2CO] ~ 1-10 %, similar to that reported in…
We present new models of the deuterium chemistry in protoplanetary disks, including, for the first time, multiply deuterated species. We use these models to explore whether observations in combination with models can give us clues as to…
We present the results of formaldehyde and methanol deuteration measurements towards the Class I low-mass protostar SVS13-A, in the framework of the IRAM 30-m ASAI (Astrochemical Surveys At IRAM) project. We detected emission lines of…
We are carrying out a physical and chemical study of the protostellar envelopes in a representative sample of IM Class 0 protostars. In our first paper (Crimier et al. 2010), we determined the physical structure (density-temperature radial…
Water is a very abundant molecule in star-forming regions. Its deuterium fractionation is an important tool for understanding its formation and evolution during the star and planet formation processes. While the HDO/H$_2$O ratio has been…
Water plays a crucial role both in the interstellar medium and on Earth. To constrain its formation mechanisms and its evolution through the star formation process, the determination of the water deuterium fractionation ratios is…
We have performed a pointed survey of N2D+ 2-1 and N2D+ 3-2 emission toward 64 N2H+-bright starless and protostellar cores in the Perseus molecular cloud using the Arizona Radio Observatory Submillimeter Telescope and Kitt Peak 12 m…
Understanding water deuterium fractionation is important for constraining the mechanisms of water formation in interstellar clouds. Observations of HDO and H$_2^{18}$O transitions were carried out towards the high-mass star-forming region…