相关论文: Gas phase Elemental abundances in Molecular cloudS…
The detection of complex organic molecules (COMs) toward dense, collapsing prestellar cores has sparked interest in the fields of astrochemistry and astrobiology, yet the mechanisms for COM formation are still debated. It was originally…
Context. The spatial distribution of molecules around starless cores is a powerful tool for studying the physics and chemistry governing the earliest stages of star formation. Aims. Our aim is to study the chemical differentiation in…
Methanol is a key species in astrochemistry since it is the most abundant organic molecule in the ISM and is thought to be the mother molecule of many complex organic species. Estimating the deuteration of methanol around young protostars…
Recent observations indicate that organic molecules are prevalent towards starless and prestellar cores. Deuteration of these molecules has not been well-studied during the starless phase. Published observations of singly-deuterated…
Cold ($\sim$10 K) and dense ($\sim$10$^{5}$ cm$^{-3}$) cores of gas and dust within molecular clouds, known as starless and dynamically evolved prestellar cores, are the birthplaces of low-mass ($M$ $\leq$ few M$_\odot$) stars. As…
Cold cores are an early step of star formation, characterized by densities > 10$^4$ cm$^{-3}$, low temperatures (< 15 K), and very low external UV radiation. We investigate the physico-chemical processes at play to tracing the origin of…
Methanol (CH$_{3}$OH) ice is abundant in space and is a key feedstock for seeding chemical complexity in interstellar and circumstellar environments. Despite its ubiquity, gas-phase methanol has only been detected in one disk around a…
Chemical models predict that in cold cores gas-phase methanol is expected to be abundant at the outer edge of the CO depletion zone, where CO is actively adsorbed. CO adsorption correlates with volume density in cold cores, and, in nearby…
GEMS is an IRAM 30m 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 dark cloud TMC 1.…
The high abundances of Complex Organic Molecules (COMs) with respect to methanol, the most abundant COM, detected towards low-mass protostars, tend to be underpredicted by astrochemical models. This discrepancy might come from the large…
Complex organic molecules are only detected toward a fraction of high-mass protostars. The goal of this work is to investigate whether high-mass disks can explain the lack of methanol emission from some massive protostellar systems. We…
Methanol and complex organic molecules have been found in cold starless cores, where a standard warm-up scenario would not work because of the absence of heat sources. A recent chemical model attributed the presence of methanol and large…
Methanol, the simplest complex organic molecule found in space, is considered a key compound necessary for the formation of chemical species of prebiotic interest. Methanol detections in protoplanetary disks remain scarce, even though it is…
Some protostellar systems show little or no millimetre line emission of complex organics. This can be interpreted as a low abundance of these molecules, alternatively they could be present in the system but are not seen in the gas. The goal…
The aim of this study is to investigate the distribution and excitation of the methanol gas around Cep A and to describe the physical conditions of the region. In addition the large scale abundance distribution is determined in order to…
Interstellar methanol is considered to be a parent species of larger, more complex organic molecules. A physicochemical simulation of infalling parcels of matter is performed for a low-mass star-forming system to trace the chemical…
We report observations of gaseous methanol in an edge-on torus surrounding the young stellar object L1551 IRS5. The peaks in the torus are separated by ~ 10,000 AU from L1551 IRS5, and contain ~ 0.03 earth masses of cold methanol. We infer…
(Abridged) We explore the chemistry of the most abundant C, O, S, and N bearing species in molecular clouds, in the context of the IRAM 30 m Large Programme Gas phase Elemental abundances in Molecular Clouds (GEMS). In this work, we aim to…
Isotopic fractionation is a very powerful tool to follow the evolution of material from one stage to the next in the star-formation process. Pre-stellar cores exhibit some of the highest levels of deuteration because their physical…
Gas phase Elemental abundances in Molecular CloudS (GEMS) is an IRAM 30m Large Program designed to estimate the S, C, N, and O depletions and gas ionization degree, X(e-), in a set of star-forming filaments of Taurus, Perseus and Orion. Our…