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dc.contributor.authorWalker, Christopher Kidd.
dc.creatorWalker, Christopher Kidd.en_US
dc.date.accessioned2011-10-31T17:12:40Z
dc.date.available2011-10-31T17:12:40Z
dc.date.issued1988en_US
dc.identifier.urihttp://hdl.handle.net/10150/184585
dc.description.abstractHow are stars formed? This is one of the most fundamental questions in astronomy. It is therefore ironic that to date, no object has been unambiguously identified as a true protostar; an object which derives the bulk of its luminosity from accretion. While this may be ironic, it is not surprising. Stars are believed to form as a result of the gravitational collapse of a portion of a molecular cloud. Theory predicts that the cloud core in which the star is formed will be cold, dense and possess hundreds of magnitudes of extinction, rendering it opaque at visible and near-infrared wavelengths. Continuum observations at far-infrared, submillimeter, and millimeter wavelengths can be used to identify candidate protostars, but spectroscopic observations are needed to detect infall. The difficulties arise when there are systematic velocity fields present in the cloud core which are not the result of infall, such as would be produced by either a molecular outflow or rotation. In this dissertation we use both observations and theoretical models to sort through these problems and develop a strategy which could be used to identify and study protostars.
dc.language.isoenen_US
dc.publisherThe University of Arizona.en_US
dc.rightsCopyright © is held by the author. Digital access to this material is made possible by the University Libraries, University of Arizona. Further transmission, reproduction or presentation (such as public display or performance) of protected items is prohibited except with permission of the author.en_US
dc.subjectStars -- Formation.en_US
dc.subjectMolecular clouds.en_US
dc.subjectProtostars.en_US
dc.titleAn observational study of the dynamics of molecular cloud cores.en_US
dc.typetexten_US
dc.typeDissertation-Reproduction (electronic)en_US
dc.identifier.oclc701865701en_US
thesis.degree.grantorUniversity of Arizonaen_US
thesis.degree.leveldoctoralen_US
dc.identifier.proquest8906395en_US
thesis.degree.disciplineAstronomyen_US
thesis.degree.disciplineGraduate Collegeen_US
thesis.degree.namePh.D.en_US
refterms.dateFOA2018-08-19T10:47:57Z
html.description.abstractHow are stars formed? This is one of the most fundamental questions in astronomy. It is therefore ironic that to date, no object has been unambiguously identified as a true protostar; an object which derives the bulk of its luminosity from accretion. While this may be ironic, it is not surprising. Stars are believed to form as a result of the gravitational collapse of a portion of a molecular cloud. Theory predicts that the cloud core in which the star is formed will be cold, dense and possess hundreds of magnitudes of extinction, rendering it opaque at visible and near-infrared wavelengths. Continuum observations at far-infrared, submillimeter, and millimeter wavelengths can be used to identify candidate protostars, but spectroscopic observations are needed to detect infall. The difficulties arise when there are systematic velocity fields present in the cloud core which are not the result of infall, such as would be produced by either a molecular outflow or rotation. In this dissertation we use both observations and theoretical models to sort through these problems and develop a strategy which could be used to identify and study protostars.


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