The 6.7- And 25-GHz methanol masers in OMC-1
Электронный научный архив УРФУ
Информация об архиве | Просмотр оригинала| Поле | Значение | |
| Заглавие |
The 6.7- And 25-GHz methanol masers in OMC-1
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| Автор |
Voronkov, M. A.
Sobolev, A. M. Ellingsen, S. P. Ostrovskii, A. B. |
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| Тематика |
ISM: INDIVIDUAL: OMC-1
ISM: MOLECULES MASERS DUST EXCITED STATES FEATURE EXTRACTION MASERS AUSTRALIA COMPACT ARRAYS DIFFERENT CLASS ISM: INDIVIDUAL: ORION MOLECULAR CLOUD 1 ISM: INDIVIDUALS ISM:MOLECULES MASER EMISSIONS METHANOL MASERS MOLECULAR CLOUDS TWO-COMPONENT METHANOL |
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| Описание |
The Australia Telescope Compact Array (ATCA) has been used to search for methanol maser emission at 6.7 GHz towards the Orion Molecular Cloud 1 (OMC-1). Two features peaking at 7.2 and -1.1 km s-1 have been detected. The former has at least two components close in both velocity and position. It is located south-east of the Orion Kleinmann-Low (Orion-KL) nebula in the region of outflow traced by the 25-GHz methanol masers and the 95-GHz methanol emission. It is shown by modelling that, in contrast to the widespread opinion that simultaneous masing of methanol transitions of different classes is impossible, there are conditions for which simultaneous masing of the class II transition at 6.7 GHz and some class I transitions (e.g. the series at 25 GHz) is possible. A relevant example is provided, in which the pumping occurs via the first torsionally excited state and is driven by radiation of the dust intermixed with the gas in the cloud. In this regime, the dust temperature is significantly lower (T ≈ 60 K) than in the case of bright 6.7-GHz masers (T > 150 K). The narrow spectral feature at -1.1 km s-1 has a brightness temperature greater than about 1400 K, which suggests that it is probably a maser. It emanates from the Orion South region and is probably associated with the approaching part of outflow seen in CO. The 25-GHz maser associated with OMC-1 was observed quasi-simultaneously with the 6.7-GHz observations. No 25-GHz emission as-sociated with the -1.1 km s-1 6.7-GHz feature towards Orion South was detected. © 2005 CSIRO.
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| Дата |
2024-04-24T12:38:24Z
2024-04-24T12:38:24Z 2005 |
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| Тип |
Article
Journal article (info:eu-repo/semantics/article) Published version (info:eu-repo/semantics/publishedVersion) |
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| Идентификатор |
Voronkov, M. A., Sobolev, A. M., Ellingsen, S. P., & Ostrovskii, A. B. (2005). The 6.7- and 25-GHz methanol masers in OMC-1. Monthly Notices of the Royal Astronomical Society, 362(3), 995–1005. doi:10.1111/j.1365-2966.2005.09374.x
0035-8711 Final All Open Access; Bronze Open Access https://academic.oup.com/mnras/article-pdf/362/3/995/2999588/362-3-995.pdf http://elar.urfu.ru/handle/10995/132580 10.1111/j.1365-2966.2005.09374.x |
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| Язык |
en
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| Права |
Open access (info:eu-repo/semantics/openAccess)
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| Формат |
application/pdf
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| Издатель |
Oxford University Press (OUP)
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| Источник |
Monthly Notices of the Royal Astronomical Society
Monthly Notices of the Royal Astronomical Society |
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