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# Complex molecules in the hot core of the low-mass protostar NGC 1333 IRAS 4A

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University of Groningen, Groningen, Groningen, Netherlands
(Impact Factor: 5.99). 12/2008; 615(1):354. DOI: 10.1086/423952
Source: arXiv

ABSTRACT

We report the detection of complex molecules (HCOOCH3, HCOOH, and CH3CN), signposts of a hot core-like region, toward the low-mass Class 0 source NGC 1333 IRAS 4A. This is the second low-mass protostar in which such complex molecules have been searched for and reported, the other source being IRAS 16293-2422. It is therefore likely that compact (a few tens of AU) regions of dense and warm gas, where the chemistry is dominated by the evaporation of grain mantles and where complex molecules are found, are common in low-mass Class 0 sources. Given that the chemical formation timescale is much shorter than the gas hot-core crossing time, it is not clear whether the reported complex molecules are formed on the grain surfaces (first-generation molecules) or in the warm gas by reactions involving the evaporated mantle constituents (second-generation molecules). We do not find evidence for large differences in the molecular abundances, normalized to the formaldehyde abundance, between the two solar-type protostars, suggesting perhaps a common origin.

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ABSTRACT: (Abstract) It is known that more than 140 interstellar and circumstellar molecules have so far been detected, mainly by means of the radio astronomy observations. Many organic molecules are also detected, including alcohols, ketons, ethers, aldehydes, and others, that are distributed from dark clouds and hot cores in the giant molecular clouds. It is believed that most of the organic molecules in space are synthesized through the grain surface reactions, and are evaporated from the grain surface when they are heated up by the UV radiation from nearby stars. On the other hand the recent claim on the detection of glycine have raised an important issue how difficult it is to confirm secure detection of weak spectra from less abundant organic molecules in the interstellar molecular cloud. Recent topics regarding observations of organic molecules in the interstellar molecular clouds, including independent observations of glycine by the 45m radio telescope and a detection of amino acetonitrile (NH2CH2CN) that is a precursor to glycine. (Keywords) Astrochemistry, Astrobiology, Interstellar molecules, Line identification, Astronomical observations
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##### Article: Hot corinos in NGC 1333-IRAS4B and IRAS2A
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##### Article: On the stability of molecules and microorganisms in interstellar and planetary environments
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