Cyanopolyynes in hot cores: modelling G305.2+0.2
We present results from a time-dependent gas-phase chemical model of a hot core based on the physical conditions of G305.2+0.2. While the cyanopolyyne HC3N has been observed in hot cores, the longer chained species, HC5N, HC7N and HC9N, have not been considered as the typical hot-core species. We pr...
| Main Authors: | , , , , |
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| Format: | Journal Article |
| Published: |
Oxford University Press
2009
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| Online Access: | http://hdl.handle.net/20.500.11937/18858 |
| _version_ | 1848749867356127232 |
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| author | Chapman, J. Millar, T. Wardle, M. Burton, M. Walsh, Andrew |
| author_facet | Chapman, J. Millar, T. Wardle, M. Burton, M. Walsh, Andrew |
| author_sort | Chapman, J. |
| building | Curtin Institutional Repository |
| collection | Online Access |
| description | We present results from a time-dependent gas-phase chemical model of a hot core based on the physical conditions of G305.2+0.2. While the cyanopolyyne HC3N has been observed in hot cores, the longer chained species, HC5N, HC7N and HC9N, have not been considered as the typical hot-core species. We present results which show that these species can be formed under hot core conditions. We discuss the important chemical reactions in this process and, in particular, show that their abundances are linked to the parent species acetylene which is evaporated from icy grain mantles. The cyanopolyynes show promise as `chemical clocks' which may aid future observations in determining the age of hot core sources. The abundance of the larger cyanopolyynes increases anddecreases over relatively short time-scales, ~102.5 yr. We present results from a non-local thermodynamic equilibrium statistical equilibrium excitation model as a series of density, temperature and column density dependent contour plots which show both the line intensities and several line ratios. These aid in the interpretation of spectral-line data, even when there is limited line informationavailable. In particular, non-detections of HC5N and HC7N in Walsh et al. are analysed and discussed. |
| first_indexed | 2025-11-14T07:27:45Z |
| format | Journal Article |
| id | curtin-20.500.11937-18858 |
| institution | Curtin University Malaysia |
| institution_category | Local University |
| last_indexed | 2025-11-14T07:27:45Z |
| publishDate | 2009 |
| publisher | Oxford University Press |
| recordtype | eprints |
| repository_type | Digital Repository |
| spelling | curtin-20.500.11937-188582017-09-13T13:43:51Z Cyanopolyynes in hot cores: modelling G305.2+0.2 Chapman, J. Millar, T. Wardle, M. Burton, M. Walsh, Andrew ISM: molecules stars: formation We present results from a time-dependent gas-phase chemical model of a hot core based on the physical conditions of G305.2+0.2. While the cyanopolyyne HC3N has been observed in hot cores, the longer chained species, HC5N, HC7N and HC9N, have not been considered as the typical hot-core species. We present results which show that these species can be formed under hot core conditions. We discuss the important chemical reactions in this process and, in particular, show that their abundances are linked to the parent species acetylene which is evaporated from icy grain mantles. The cyanopolyynes show promise as `chemical clocks' which may aid future observations in determining the age of hot core sources. The abundance of the larger cyanopolyynes increases anddecreases over relatively short time-scales, ~102.5 yr. We present results from a non-local thermodynamic equilibrium statistical equilibrium excitation model as a series of density, temperature and column density dependent contour plots which show both the line intensities and several line ratios. These aid in the interpretation of spectral-line data, even when there is limited line informationavailable. In particular, non-detections of HC5N and HC7N in Walsh et al. are analysed and discussed. 2009 Journal Article http://hdl.handle.net/20.500.11937/18858 10.1111/j.1365-2966.2008.14144.x Oxford University Press unknown |
| spellingShingle | ISM: molecules stars: formation Chapman, J. Millar, T. Wardle, M. Burton, M. Walsh, Andrew Cyanopolyynes in hot cores: modelling G305.2+0.2 |
| title | Cyanopolyynes in hot cores: modelling G305.2+0.2 |
| title_full | Cyanopolyynes in hot cores: modelling G305.2+0.2 |
| title_fullStr | Cyanopolyynes in hot cores: modelling G305.2+0.2 |
| title_full_unstemmed | Cyanopolyynes in hot cores: modelling G305.2+0.2 |
| title_short | Cyanopolyynes in hot cores: modelling G305.2+0.2 |
| title_sort | cyanopolyynes in hot cores: modelling g305.2+0.2 |
| topic | ISM: molecules stars: formation |
| url | http://hdl.handle.net/20.500.11937/18858 |