CO/CO2 Molecular Number Ratio Produced by ion Irradiation of Ices

We have quantitatively studied, by infrared absorption spectroscopy, the CO/CO^sub 2^ molecular number ratio after ion irradiation of ices and mixtures containing astrophysically relevant species such as CO, CO^sub 2^, H^sub 2^O, CH^sub 4^, CH^sub 3^OH, NH^sub 3^, O^sub 2^, and N^sub 2^ at 12-15 K....

Full description

Saved in:
Bibliographic Details
Published in:Astrophysics and space science 2000-01, Vol.274 (3), p.643
Main Authors: Satorre, Ma, Palumbo, Me, Strazzulla, G
Format: Article
Language:English
Subjects:
Absorption spectroscopy
Astrophysics
Carbon dioxide
Irradiation
Sublimation
Temperature
Citations: Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:We have quantitatively studied, by infrared absorption spectroscopy, the CO/CO^sub 2^ molecular number ratio after ion irradiation of ices and mixtures containing astrophysically relevant species such as CO, CO^sub 2^, H^sub 2^O, CH^sub 4^, CH^sub 3^OH, NH^sub 3^, O^sub 2^, and N^sub 2^ at 12-15 K. The ratios have also been measured after warm up to temperatures between 12 and 200 K. As a general result we find that the CO/CO^sub 2^ ratio decreases with the irradiation dose (amount of energy deposited on the sample). In all of the studied mixtures, as expected, it decreases with increasing temperature because of CO sublimation. However the temperature where CO sublimes strongly depends on the initial mixture, remaining at a temperature over 100 K in some cases. Our results might be relevant to interpret the observed CO/CO^sub 2^ ratio in several astrophysical scenarios such as planetary icy surfaces and ice mantles on grains in the interstellar medium.[PUBLICATION ABSTRACT]
ISSN:0004-640X
1572-946X
DOI:10.1023/A:1026512023613