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Type of Document	Dissertation
Author	Lane, Benjamin F.
Author's Email Address	ben AT its.caltech.edu
URN	etd-03122003-112232
Persistent URL	http://resolver.caltech.edu/CaltechETD:etd-03122003-112232
Title	High-precision infra-red stellar interferometry
Degree	PhD
Option	Geological and Planetary Sciences
Advisory Committee	Advisor Name Title Bruce Murray Committee Chair David J. Stevenson Committee Member Geoffrey Blake Committee Member M. Mark Colavita Committee Member Michael E. Brown Committee Member Shrinivas R. Kulkarni Committee Member
Keywords	stellar astronomy Cepheids interferometry infrared instrumentation low-mass stars Brown dwarfs
Date of Defense	2003-02-20
Availability	unrestricted
Abstract This dissertation describes work performed at the Palomar Testbed Interferometer (PTI) during 1998-2002. Using PTI, we developed a method to measure stellar angular diameters in the 1-3 milli-arcsecond range with a precision of better than 5%. Such diameter measurements were used to measure the mass-radius relations of several lower main sequence stars and hence verify model predictions for these stars. In addition, by measuring the changes in Cepheid angular diameters during the pulsational cycle and applying a Baade-Wesselink analysis we are able to derive the distances to two galactic Cepheids (eta Aql & zeta Gem) with a precision of order 10%; such distance determinations provide an independent calibration of the Cepheid period-luminosity relations that underpin current estimates of cosmic distance scales. Second, we used PTI and the adaptive optics facility at the Keck Telescope on Mauna Kea to resolve the low mass binary systems BY Dra and GJ 569B, resulting in dynamical mass determinations for these systems. GJ 569B most likely contains at least one substellar component, and as such represents the first dynamical mass determination of a brown dwarf. Finally, a new observing technique - dual-star phase referencing - was developed and demonstrated at PTI. Phase referencing allows interferometric observations of stars previously too faint to observe, and is a prerequisite for large-scale interferometric astrometry programs such as the one planned for the Keck Interferometer; interferometric astrometry is a promising technique for the study of extra-solar planetary systems, particularly ones with long-period planets.
Files	Filename       Size       Approximate Download Time (Hours:Minutes:Seconds)     28.8 Modem   56K Modem   ISDN (64 Kb)   ISDN (128 Kb)   Higher-speed Access    thesis.pdf 1.59 Mb 00:07:20 00:03:46 00:03:18 00:01:39 00:00:08   thesis.ps 15.96 Mb 01:13:54 00:38:00 00:33:15 00:16:37 00:01:25