The HNC/HCN ratio in comets

被引：21

作者：

Irvine, WM ^{[1
]}

Dickens, JE

Lovell, AJ

Schloerb, FP

Senay, M

Bergin, EA

Jewitt, D

Matthews, HE

机构：

[1] Univ Massachusetts, Five Coll Radio Astron Observ, Amherst, MA 01003 USA

[2] Smithsonian Astrophys Observ, Cambridge, MA 02138 USA

[3] Univ Hawaii, Inst Astron, Honolulu, HI 96822 USA

[4] Joint Astron Ctr, Hilo, HI 96720 USA

来源：

EARTH MOON AND PLANETS | 1997年 / 78卷 / 1-3期

关键词：

comets; interstellar molecules;

D O I：

10.1023/A:1006202823878

中图分类号：

P1 [天文学];

学科分类号：

0704 ;

摘要：

The abundance ratio of the isomers HCN and HNC has been investigated in comet Hale-Bopp (C/1995 O1) through observations of the J = 4-3 rotational transitions of both species for heliocentric distances 0.93 < r<3 AU, both pre- and post-perihelion. After correcting for the optical depth of the stronger HCN line, we find that the column density ratio of HNC/HCN in our telescope beam increases significantly as the comet approaches the Sun. We compare this behavior to that predicted from an ion-molecule chemical model and conclude that the HNC is produced in significant measure by chemical processes in the coma; i.e., for comet Hale-Bopp, HNC is not a parent molecule sublimating from the nucleus.

引用

页码：29 / 35

页数：7

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