Title

The HNC/HCN ratio in comets

Publication Date

1997

Journal or Book Title

EARTH MOON AND PLANETS

Abstract

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 insignificant measure by chemical processes in the coma; i.e., for comet Hale-Bopp, HNC is not a parent molecule sublimating from the nucleus.

Comments

The published version is located at http://www.springerlink.com/content/u467634mxwkl8245/

Volume

78

Pages

29-35

Issue

1-3

This document is currently not available here.

Share

COinS