MNRAS-B.pdf (1.38 MB)
Applying laboratory thermal desorption data in an interstellar context: sublimation of methanol thin films
journal contribution
posted on 2023-06-08, 17:19 authored by Simon D Green, Amandeep S Bolina, Rui Chen, Mark P Collings, Wendy BrownWendy Brown, Martin R S McCoustraMethods by which experimental measurements of thermal desorption can be applied in astrophysical environments have been developed, using the sublimation of solid methanol as an example. The temperature programmed desorption of methanol from graphitic, amorphous silica and polycrystalline gold substrates was compared, with the kinetic parameters of desorption extracted by either a leading edge analysis or by fitting using a stochastic integration method. At low coverages, the desorption shows a substrate-dependent fractional order. However, at higher coverages methanol desorption is zeroth order with kinetic parameters independent of substrate. Using a kinetic model based on the stochastic integration analyses, desorption under astrophysically relevant conditions can be simulated. We find that the chemical and morphological nature of the substrate has relatively little impact on the desorption temperature of solid methanol, and that the substrate independent zeroth-order kinetics can provide a satisfactory model for desorption in astrophysical environments. Uncertainties in the heating rate and the distribution of grain sizes will have the largest influence on the range of desorption temperature. These conclusions are likely to be generally applicable to all species in dust grain ice mantles.
History
Publication status
- Published
File Version
- Published version
Journal
Monthly Notices of the Royal Astronomical SocietyISSN
0035-8711Publisher
Wiley-BlackwellExternal DOI
Issue
1Volume
398Page range
357 - 367Department affiliated with
- Chemistry Publications
Full text available
- Yes
Peer reviewed?
- Yes
Legacy Posted Date
2014-07-21First Open Access (FOA) Date
2014-07-21First Compliant Deposit (FCD) Date
2014-07-21Usage metrics
Categories
No categories selectedKeywords
Licence
Exports
RefWorks
BibTeX
Ref. manager
Endnote
DataCite
NLM
DC