First detection of cyanamide (NH2CN) towards solar-type protostars

被引：51

作者：

Coutens, A. ^{[1
]}

Willis, E. R. ^{[2
,3
]}

Garrod, R. T. ^{[2
,3
]}

Mueller, H. S. P. ^{[4
]}

Bourke, T. L. ^{[5
]}

Calcutt, H. ^{[6
,7
]}

Drozdovskaya, M. N. ^{[8
]}

Jorgensen, J. K. ^{[6
,7
]}

Ligterink, N. F. W. ^{[9
]}

Persson, M. V. ^{[10
]}

Stephan, G. ^{[2
,3
]}

van der Wiel, M. H. D. ^{[11
]}

van Dishoeck, E. F. ^{[9
,12
]}

Wampfler, S. F. ^{[8
]}

机构：

[1] Univ Bordeaux, Lab Astrophys Bordeaux, CNRS, B18N,Allee Geoffroy St Hilaire, F-33615 Pessac, France

[2] Univ Virginia, Dept Chem, Charlottesville, VA 22904 USA

[3] Univ Virginia, Dept Astron, Charlottesville, VA 22904 USA

[4] Univ Cologne, Phys Inst 1, Zulpicher Str 77, D-50937 Cologne, Germany

[5] SKA Org, Jodrell Bank Observ, Macclesfield SK11 9DL, Cheshire, England

[6] Univ Copenhagen, Niels Bohr Inst, Ctr Star & Planet Format, Oster Voldgade 5-7, DK-1350 Copenhagen K, Denmark

[7] Univ Copenhagen, Nat Hist Museum Denmark, Oster Voldgade 5-7, DK-1350 Copenhagen K, Denmark

[8] Univ Bern, Ctr Space & Habitabil, Sidlerstr 5, CH-3012 Bern, Switzerland

[9] Leiden Univ, Leiden Observ, POB 9513, NL-2300 RA Leiden, Netherlands

[10] Chalmers Univ Technol, Onsala Space Observ, Dept Space Earth & Environm, S-43992 Onsala, Sweden

[11] ASTRON Netherlands Inst Radio Astron, POB 2, NL-7990 AA Dwingeloo, Netherlands

[12] Max Planck Inst Extraterr Phys MPE, Giessenbachstr 1, D-85748 Garching, Germany

来源：

ASTRONOMY & ASTROPHYSICS | 2018年 / 612卷

基金：

新加坡国家研究基金会; 欧洲研究理事会;

关键词：

astrochemistry; astrobiology; ISM: molecules; stars: protostars; ISM: individual objects: IRAS 16293-2422; ISM: individual objects: NGC 1333 IRAS2A; IRAS; 16293-2422; MOLECULAR-SPECTROSCOPY; COLOGNE DATABASE; CARBODIIMIDE; MILLIMETER; SUBMILLIMETER; ROTATION; SPECTRUM; CH3NCO; DUST;

D O I：

10.1051/0004-6361/201732346

中图分类号：

P1 [天文学];

学科分类号：

0704 ;

摘要：

Searches for the prebiotically relevant cyanamide (NH2CN) towards solar-type protostars have not been reported in the literature. We present here the first detection of this species in the warm gas surrounding two solar-type protostars, using data from the Atacama Large Millimeter/Submillimeter Array Protostellar Interferometric Line Survey (PILS) of IRAS 16293-2422 B and observations from the LRAM Plateau de Bure Interferometer of NGC 1333 IRAS2A. We also detected the deuterated and C-13 isotopologs of NH2CN towards IRAS 16293-2422 B. This is the first detection of NHDCN in the interstellar medium. Based on a local thermodynamic equilibrium analysis, we find that the deuteration of cyanamide (similar to 1.7%) is similar to that of formamide (NH2CHO), which may suggest that these two molecules share NH2 as a common precursor. The NH2CN/NH2CHO abundance ratio is about 0.2 for IRAS 16293-2422 B and 0.02 for IRAS2A, which is comparable to the range of values found for Sgr B2. We explored the possible formation of NH2CN on grains through the NH2 + CN reaction using the chemical model MAGICKAL. Grain-surface chemistry appears capable of reproducing the gas-phase abundance of NH2CN with the correct choice of physical parameters.

引用

页数：8

共 46 条

[1] A λ=1.3 mm and 2 mm molecular line survey towards M 82 [J].