PC
P. Caselli
Authored
20 records found
Gas phase Elemental abundances in Molecular cloudS (GEMS)
IV. Observational results and statistical trends
Gas phase Elemental abundances in Molecular CloudS (GEMS) is an IRAM 30 m Large Program designed to provide estimates of the S, C, N, and O depletions and gas ionization degree, X(e-), in a selected set of star-forming filaments of Taurus, Perseus, and Orion. Our immediate goal i
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Photoprocessing of H2S on dust grains Building S chains in translucent clouds and comets
Building S chains in translucent clouds and comets
Context. Sulfur is a biogenic element used as a tracer of the evolution of interstellar clouds to stellar systems. However, most of the expected sulfur in molecular clouds remains undetected. Sulfur disappears from the gas phase in two steps. The first depletion occurs during the
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Gas phase Elemental abundances in Molecular cloudS (GEMS)
VII. Sulfur elemental abundance
Context. Gas phase Elemental abundances in molecular CloudS (GEMS) is an IRAM 30-m Large Program aimed at determining the elemental abundances of carbon (C), oxygen (O), nitrogen (N), and sulfur (S) in a selected set of prototypical star-forming filaments. In particular, the elem
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Evolutionary view through the starless cores in Taurus
Deuteration in TMC 1-C and TMC 1-CP
Context. The chemical and physical evolution of starless and pre-stellar cores are of paramount importance to understanding the process of star formation. The Taurus Molecular Cloud cores TMC 1-C and TMC 1-CP share similar initial conditions and provide an excellent opportunity t
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Evolutionary view through the starless cores in Taurus
Deuteration in TMC 1-C and TMC 1-CP
Context. The chemical and physical evolution of starless and pre-stellar cores are of paramount importance to understanding the process of star formation. The Taurus Molecular Cloud cores TMC 1-C and TMC 1-CP share similar initial conditions and provide an excellent opportunity t
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Gas phase Elemental abundances in Molecular cloudS (GEMS)
I. the prototypical dark cloud TMC 1
GEMS is an IRAM 30 m Large Program whose aim is determining the elemental depletions and the ionization fraction in a set of prototypical star-forming regions. This paper presents the first results from the prototypical dar
...
Gas phase Elemental abundances in Molecular cloudS (GEMS)
I. the prototypical dark cloud TMC 1
GEMS is an IRAM 30 m Large Program whose aim is determining the elemental depletions and the ionization fraction in a set of prototypical star-forming regions. This paper presents the first results from the prototypical dar
...
Gas phase Elemental abundances in Molecular cloudS (GEMS)
I. the prototypical dark cloud TMC 1
GEMS is an IRAM 30 m Large Program whose aim is determining the elemental depletions and the ionization fraction in a set of prototypical star-forming regions. This paper presents the first results from the prototypical dar
...
Gas phase Elemental abundances in Molecular cloudS (GEMS)
I. the prototypical dark cloud TMC 1
GEMS is an IRAM 30 m Large Program whose aim is determining the elemental depletions and the ionization fraction in a set of prototypical star-forming regions. This paper presents the first results from the prototypical dar
...
Gas phase Elemental abundances in Molecular cloudS (GEMS)
I. the prototypical dark cloud TMC 1
GEMS is an IRAM 30 m Large Program whose aim is determining the elemental depletions and the ionization fraction in a set of prototypical star-forming regions. This paper presents the first results from the prototypical dar
...
Gas phase Elemental abundances in Molecular cloudS (GEMS)
I. the prototypical dark cloud TMC 1
GEMS is an IRAM 30 m Large Program whose aim is determining the elemental depletions and the ionization fraction in a set of prototypical star-forming regions. This paper presents the first results from the prototypical dar
...
Gas phase Elemental abundances in Molecular cloudS (GEMS)
I. the prototypical dark cloud TMC 1
GEMS is an IRAM 30 m Large Program whose aim is determining the elemental depletions and the ionization fraction in a set of prototypical star-forming regions. This paper presents the first results from the prototypical dar
...
Gas phase Elemental abundances in Molecular cloudS (GEMS)
I. the prototypical dark cloud TMC 1
GEMS is an IRAM 30 m Large Program whose aim is determining the elemental depletions and the ionization fraction in a set of prototypical star-forming regions. This paper presents the first results from the prototypical dar
...
Gas phase Elemental abundances in Molecular cloudS (GEMS)
I. the prototypical dark cloud TMC 1
GEMS is an IRAM 30 m Large Program whose aim is determining the elemental depletions and the ionization fraction in a set of prototypical star-forming regions. This paper presents the first results from the prototypical dar
...
Gas phase Elemental abundances in Molecular cloudS (GEMS)
I. the prototypical dark cloud TMC 1
GEMS is an IRAM 30 m Large Program whose aim is determining the elemental depletions and the ionization fraction in a set of prototypical star-forming regions. This paper presents the first results from the prototypical dar
...
Warm dust surface chemistry
H<sub>2</sub>and HD formation
Context. Molecular hydrogen (H2) is the main constituent of the gas in the planet-forming disks that surround many pre-main-sequence stars. H2 can be incorporated in the atmosphere of the nascent giant planets in disks. Deuterium hydride (HD) has been detected in a few disks and
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Warm dust surface chemistry in protoplanetary disks
Formation of phyllosilicates
Context. The origin of the reservoirs of water on Earth is debated. The Earth's crust may contain at least three times more water than the oceans. This crust water is found in the form of phyllosilicates, whose origin probably differs from that of the oceans. Aims. We test the po
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Interstellar ices as witnesses of star formation
Selective deuteration of water and organic molecules unveiled
Observations of star-forming environments revealed that the abundances of some deuterated interstellar molecules are markedly larger than the cosmic D/H ratio of 10-5. Possible reasons for this pointed to grain surface chemistry. However, organic molecules and water, which are bo
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Interstellar ices as witnesses of star formation
Selective deuteration of water and organic molecules unveiled
Observations of star-forming environments revealed that the abundances of some deuterated interstellar molecules are markedly larger than the cosmic D/H ratio of 10-5. Possible reasons for this pointed to grain surface chemistry. However, organic molecules and water, which are bo
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Water formation on bare grains
When the chemistry on dust impacts interstellar gas
Context. Water and O2 are important gas phase ingredients for cooling dense gas when forming stars. On dust grains, H2O is an important constituent of the icy mantle in which a complex chemistry is taking place, as revealed by hot core observations. The formation of water can occ
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