A sensitive 3 mm line survey of L483: a broad view of the chemical composition of a core around a Class 0 object

Abstract

We present an IRAM 30m line survey of the dense core L483 in the 3 mm band. We detected 71 molecules (140 including different isotopologs), most of which are present in the cold and quiescent ambient cloud. Of particular interest among the detected molecules are the cis isomer of HCOOH, the complex organic molecules HCOOCH3, CH3OCH3, and C2H5OH, a wide variety of carbon chains, nitrogen oxides like N2O, and saturated molecules like CH3SH. In general, fractional molecular abundances in L483 are systematically lower than in TMC-1 (especially for carbon chains), tend to be higher than in L1544 and B1-b, and are similar to those in L1527. Apart from the overabundance of carbon chains in TMC-1, we find that L483 does not have a marked chemical differentiation with respect to starless/prestellar cores like TMC-1 and L1544, although it does chemically differentiate from Class 0 hot corino sources like IRAS 16293-2422. This fact suggests that the chemical composition of the ambient cloud of some Class 0 sources could be largely inherited from the dark cloud starless/prestellar phase. We also derived isotopic ratios for a variety of molecules, some of which show isotopic anomalies like an extreme depletion in 13C for one of the two isotopologs of c-C3H2, a drastic enrichment in 18O for SO and HNCO (SO being also largely enriched in 17O), and different abundances for the two 13C substituted species of C2H and the two 15N substituted species of N2H+. We report the first detection in space of some minor isotopologs like c-C3D. The exhaustive chemical characterization of L483 presented here, together with similar studies of other prestellar and protostellar sources, should allow us to identify the main factors that regulate the chemical composition of cores along the process of formation of low-mass protostars.

Published in A&A. Abstract abridged. Changes with respect to previous version: english edited and updated information on deuterated molecules in IRAS 16293-2422

References in corpus (20)

• Formation of complex organic molecules in cold objects: the role of gas phase reactions
• Molecular Evolution and Star Formation: From Prestellar Cores to Protostellar Cores
• Formation of Complex Molecules in Prestellar Cores: a Multilayer Approach
• Modeling Complex Organic Molecules in dense regions: Eley-Rideal and complex induced reaction
• Discovery of Fulminic Acid, HCNO, in Dark Clouds
• Discovery of interstellar ketenyl (HCCO), a surprisingly abundant radical
• The interstellar chemistry of C3H and C3H2 isomers
• Galactic interstellar 18O/17O ratios - a radial gradient?
• Laboratory Characterization and Astrophysical Detection of Vibrationally Excited States of Vinyl Cyanide in Orion-KL
• Chemical complexity induced by efficient ice evaporation in the Barnard 5 molecular cloud
• Revised Models of Interstellar Nitrogen Isotopic Fractionation
• Detection of the HC${}_3$NH${}^{+}$ and HCNH${}^{+}$ ions in the L1544 pre-stellar core
• Oxygen fractionation in dense molecular clouds
• Detection of HC${}_5$N and HC${}_7$N Isotopologues in TMC-1 with the Green Bank Telescope
• Chemical nitrogen fractionation in dense molecular clouds
• Interstellar 12C/13C from CH+ absorption lines: Results from an extended survey
• Water in star-forming regions with Herschel (WISH) V. The physical conditions in low-mass protostellar outflows revealed by multi-transition water observations
• The effect of selective desorption mechanisms during interstellar ice formation
• A study of singly deuterated cyclopropenylidene c-C3HD in protostar IRAS 16293-2422
• A Search for O_2 in CO-depleted Molecular Cloud Cores with Herschel

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• Prestellar grain-surface origins of deuterated methanol in comet 67P/Churyumov-Gerasimenko
• Discovery of the acetyl cation, CH3CO+, in space and in the laboratory
• Interstellar detection of the simplest aminocarbyne, H2NC: an ignored but abundant molecule
• Sulphur and carbon isotopes towards Galactic centre clouds
• A search for cloud cores affected by shocked carbon chain chemistry in L1251
• The First Detection of CH${}_2$CN in a Protoplanetary Disk
• First detection of doubly deuterated methyl acetylene (CHD2CCH and CH2DCCD)
• Rotational spectrum of isotopic methyl mercaptan, (13)CH3SH, in the laboratory and towards Sagittarius B2(N2)
• Binding energies of ethanol and ethylamine on interstellar water ices: synergy between theory and experiments
• Physicochemical models: source-tailored or generic?
• Rotational spectroscopy of singly ${}^{13}$C substituted isotopomers of propyne and determination of a semi-empirical equilibrium structure