Related papers: H-D Substitution in Interstellar Solid Methanol: A…
The first observations of deuterium and oxygen in the Local Interstellar Medium (LISM) obtained with the Far Ultraviolet Spectroscopic Explorer (FUSE) can be used to search for local abundance variations. While the very limited sample of…
We observed 14 methanol transitions near lambda=2 mm in Galactic star-forming regions. Broad, quasi-thermal J(0)-J(-1)E methanol lines near 157 GHz were detected toward 73 sources. Together with the 6(-1)-5(0)E and 5(-2)-6(-1)E lines at 133…
The abundance of deuterium in the interstellar gas in front of the Sun gives insight into the processes of filtration of neutral interstellar species through the heliospheric interface and potentially into the chemical evolution of the…
Recent studies suggest that infrared dark clouds (IRDCs) have the potential of harboring the earliest stages of massive star formation and indeed evidence for this is found toward distinct regions within them. We present a study with the…
We report the measurement of the primordial D/H abundance ratio towards QSO \object. The column density of the hydrogen in the $z \simeq 2.536$ Lyman limit system is high, \lnhi $= 19.422 \pm 0.009$ \cmm, allowing for the deuterium to be…
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…
In this work, we study deuterium fractionation in four starless cores in the low-mass star-forming region L1688 in the Ophiuchus molecular cloud. We study how the deuterium fraction ($R_D$) changes with environment, compare deuteration of…
We present a new measurement of the deuterium-to-hydrogen ratio (D/H) in the Lyman limit absorption system at $z = 3.572$ towards Q1937--1009. We use an improved method to measure D/H in QSO absorption systems, which includes extra…
Deuteration is sensitive to environmental conditions in star-forming regions. To investigate NH$_2$D chemistry, we compared the spatial distribution of ortho-NH$_2$D $1_{11}^s-1_{01}^a$, NH$_3$(1,1) and NH$_3$(2,2) in 12 late-stage massive…
We report the discovery of a widespread population of collisionally excited methanol J = 4_{-1} to 3$_0 E sources at 36.2 GHz from the inner 66'x18' (160x43 pc) of the Galactic center. This spectral feature was imaged with a spectral…
Deuterium fractionation provides a key diagnostic of the physical and chemical evolution of prestellar and protostellar cores, where it is strongly linked to CO depletion in cold, dense gas. We present the first spatially resolved maps of…
In this work we present the predictions of a modified version of the ``two-infall model'' (Chiappini et al. 1997) for the evolution of 3He, 4He and D in the solar vicinity, as well as their distributions along the Galactic disk. In…
The amount of deuterium relative to hydrogen (D/H) in clouds with close to primordial abundance seen at high redshift in the spectra of distant quasars currently provides the best estimate of the baryonic density of the Universe. The first…
Context. Interstellar dust particles, which represent 1% of the total mass, are recognized to be very powerful interstellar catalysts in star-forming regions. The presence of dust can have a strong impact on the chemical composition of…
The deuterium abundances inferred from observations of the interstellar medium within 1-2 kpc of the Sun range over a factor of three and the corresponding oxygen abundances show an even larger dispersion. While the lower D (and O)…
Deuterium fractionation processes in the interstellar medium (ISM) have been shown to be highly efficient in the family of nitrogen hydrides. To date, observations were limited to ammonia (NH$_2$D, NHD$_2$, ND$_3$) and imidogen radical (ND)…
The details of the Solar system's formation are still heavily debated. Questions remain about the formation locations of the giant planets, and the degree to which volatile material was mixed throughout the proto-planetary system. One…
During the next decade a tremendous advance will take place in instrumentation for spectroscopy of the interstellar medium. Major new facilities (ALMA, SOFIA, APEX, LMT, Herschel and others) will be constructed and commissioned, so that the…
It has been pointed out by various astronomers that very interesting relationship exists between interstellar alcohols and the corresponding thiols (sulfur analogue of alcohols) as far as the spectroscopic properties and chemical abundances…
Context: Reconnaissance of feasibility of detection of interstellar neutral D by the forthcoming NASA SMEX mission IBEX. Aims: To investigate by numerical simulations the absolute density and flux at Earth orbit of neutral interstellar D…