The properties of the SC stars and chemical composition of UY centauri

 

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dc.contributor.author Catchpole, Robin Michael en_ZA
dc.date.accessioned 2016-02-11T06:57:36Z
dc.date.available 2016-02-11T06:57:36Z
dc.date.issued 1982 en_ZA
dc.identifier.citation Catchpole, R. 1982. The properties of the SC stars and chemical composition of UY centauri. University of Cape Town. en_ZA
dc.identifier.uri http://hdl.handle.net/11427/16968
dc.description Bibliography: p. 185-292. en_ZA
dc.description.abstract This is primarily an observational thesis concerned firstly, with improving our knowlegde of the 12 SC stars, defined as a group by Catchpole and Feast (1971) and secondly, with determining the chemical composition of UY Cen, the brightest member of the group. An atlas, based on 13 A mm-1 spectra is presented for the S star π Gru and the C star 19 Psc between 5430 and 6850 A. In order to overcome the problems caused by the high density of absorption lines, we use a method of line identification that relies on the statistical interpretation of intensity against wavelength-agreement and Intensity against Excitation diagrams. The objective being to determine which elements are present in the spectrum before assigning identifications to individual lines. The spectrum is found to be rich in 's' process elements and shows weak molecules of both carbides, oxides and hydrides. U to L (0.36 to 3.4μ) photometry is listed for all the stars and shows them to be a very homogeneous group. A set of wavelengths derived from the line list is used to find the radial velocities of all the stars. A solar model atmosphere, with pure absorption as the method of line formation, is used to derive astrophysical log gf values from solar equivalent widths and meteor abundances. The model atmosphere also shows, that for our set of CN equivalent widths, both the CN abundance and the derived isotope ratio depend on the adopted C/O ratio. en_ZA
dc.language.iso eng en_ZA
dc.subject.other Astronomy en_ZA
dc.title The properties of the SC stars and chemical composition of UY centauri en_ZA
dc.type Doctoral Thesis
uct.type.publication Research en_ZA
uct.type.resource Thesis en_ZA
dc.publisher.institution University of Cape Town
dc.publisher.faculty Faculty of Science en_ZA
dc.publisher.department Department of Astronomy en_ZA
dc.type.qualificationlevel Doctoral
dc.type.qualificationname PhD en_ZA
uct.type.filetype Text
uct.type.filetype Image
dc.identifier.apacitation Catchpole, R. M. (1982). <i>The properties of the SC stars and chemical composition of UY centauri</i>. (Thesis). University of Cape Town ,Faculty of Science ,Department of Astronomy. Retrieved from http://hdl.handle.net/11427/16968 en_ZA
dc.identifier.chicagocitation Catchpole, Robin Michael. <i>"The properties of the SC stars and chemical composition of UY centauri."</i> Thesis., University of Cape Town ,Faculty of Science ,Department of Astronomy, 1982. http://hdl.handle.net/11427/16968 en_ZA
dc.identifier.vancouvercitation Catchpole RM. The properties of the SC stars and chemical composition of UY centauri. [Thesis]. University of Cape Town ,Faculty of Science ,Department of Astronomy, 1982 [cited yyyy month dd]. Available from: http://hdl.handle.net/11427/16968 en_ZA
dc.identifier.ris TY - Thesis / Dissertation AU - Catchpole, Robin Michael AB - This is primarily an observational thesis concerned firstly, with improving our knowlegde of the 12 SC stars, defined as a group by Catchpole and Feast (1971) and secondly, with determining the chemical composition of UY Cen, the brightest member of the group. An atlas, based on 13 A mm-1 spectra is presented for the S star π Gru and the C star 19 Psc between 5430 and 6850 A. In order to overcome the problems caused by the high density of absorption lines, we use a method of line identification that relies on the statistical interpretation of intensity against wavelength-agreement and Intensity against Excitation diagrams. The objective being to determine which elements are present in the spectrum before assigning identifications to individual lines. The spectrum is found to be rich in 's' process elements and shows weak molecules of both carbides, oxides and hydrides. U to L (0.36 to 3.4μ) photometry is listed for all the stars and shows them to be a very homogeneous group. A set of wavelengths derived from the line list is used to find the radial velocities of all the stars. A solar model atmosphere, with pure absorption as the method of line formation, is used to derive astrophysical log gf values from solar equivalent widths and meteor abundances. The model atmosphere also shows, that for our set of CN equivalent widths, both the CN abundance and the derived isotope ratio depend on the adopted C/O ratio. DA - 1982 DB - OpenUCT DP - University of Cape Town LK - https://open.uct.ac.za PB - University of Cape Town PY - 1982 T1 - The properties of the SC stars and chemical composition of UY centauri TI - The properties of the SC stars and chemical composition of UY centauri UR - http://hdl.handle.net/11427/16968 ER - en_ZA


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