Low-mass star formation and the initial mass function in young clusters
AuthorLuhman, Kevin Lee, 1971-
KeywordsPhysics, Astronomy and Astrophysics.
AdvisorRieke, George H.
MetadataShow full item record
PublisherThe University of Arizona.
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.
AbstractI have used optical and near-infrared spectroscopy and imaging to measure spectral types and luminosities for young (τ < 10 Myr), embedded (Aᵥ = 0-50), low-mass (0.1-1 M(⊙)) stars in three nearby (d < 300 pc) clusters: L1495E, IC 348, and ρ Ophiuchi. In conjunction with theoretical evolutionary tracks, I have derived the star formation history and initial mass function for each stellar population. A large number of brown dwarf candidates have been identified in the photometry, several of which are confirmed through spectroscopy. Finally, I have measured the frequency and survival times of circumstellar disks and investigated the photometric and spectroscopic properties of protostars. In § 2, I apply observational tests to the available sets of evolutionary models for low-mass stars, concluding that the calculations of D'Antona & Mazzitelli are preferred for the range of masses and ages considered here. In § 3 and § 4, I examine in detail the spectroscopic characteristics and substellar nature of two brown dwarf candidates. The study then expands to include the populations within the clusters L1495E (§ 5), IC 348 (§ 6), and ρ Ophiuchi (§ 7). In § 8, I briefly discuss the past, present, and future of scientific research related to this thesis.
Degree ProgramGraduate College