On the Road to Imaging Extrasolar Planets: Null Results, other Discoveries along the Way, and Signposts for the Future

Persistent Link:
http://hdl.handle.net/10150/145102
Title:
On the Road to Imaging Extrasolar Planets: Null Results, other Discoveries along the Way, and Signposts for the Future
Author:
Nielsen, Eric Ludwig
Issue Date:
2011
Publisher:
The University of Arizona.
Rights:
Copyright © 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.
Abstract:
I present my experiences designing, conducting, and analyzing the results from direct imaging surveys for extrasolar giant planets. Using the young, low mass star AB Dor C, I show that models for low-mass stars and brown dwarfs at young ages are good representations of reality. I discuss the design of the Simultaneous Differential Imaging survey, and how Monte Carlo simulations of giant planet populations allow for the design of imaging surveys, including the choice of target list, that maximizes the expected yield of extrasolar planets. With the conclusion of the SDI survey, I examine how its null result for planets sets constraints on the allowable populations of long-period exoplanets, finding that fewer than 8% of sun-like stars can have planets more massive than 4 Jupiter masses between 20 and 100 AU, at 68% confidence. When I include null results from other direct imaging surveys, these constraints are further strengthened: at 68% confidence, fewer than 20% of sun-like stars can have planets more massive than 4 Jupiter masses, at orbital semi-major axes between 8.1 and 911 AU. Even when applying the mass scaling of Johnson et al. (2007), and the "cold start" planet luminosity models of Fortney et al. (2008), the results remain consistent: giant planets are rare at large separations around sun-like stars. I explain how these constraints and planet simulations were used to design the Gemini South NICI Planet-Finding Campaign survey and target list, in order to maximize the chance of NICI detecting a planet, and so giving the campaign the greatest ability to strongly constrain populations of extrasolar giant planets, even in the case of a null result. Finally, I discuss future directions for direct imaging planet searches, and the steps needed tomove fromexisting surveys to a truly unified distribution of extrasolar planet populations.
Type:
Electronic Dissertation; text
Degree Name:
Ph.D.
Degree Level:
doctoral
Degree Program:
Graduate College; Astronomy
Degree Grantor:
University of Arizona
Advisor:
Close, Laird M.

Full metadata record

DC FieldValue Language
dc.language.isoenen_US
dc.titleOn the Road to Imaging Extrasolar Planets: Null Results, other Discoveries along the Way, and Signposts for the Futureen_US
dc.creatorNielsen, Eric Ludwigen_US
dc.contributor.authorNielsen, Eric Ludwigen_US
dc.date.issued2011-
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.description.abstractI present my experiences designing, conducting, and analyzing the results from direct imaging surveys for extrasolar giant planets. Using the young, low mass star AB Dor C, I show that models for low-mass stars and brown dwarfs at young ages are good representations of reality. I discuss the design of the Simultaneous Differential Imaging survey, and how Monte Carlo simulations of giant planet populations allow for the design of imaging surveys, including the choice of target list, that maximizes the expected yield of extrasolar planets. With the conclusion of the SDI survey, I examine how its null result for planets sets constraints on the allowable populations of long-period exoplanets, finding that fewer than 8% of sun-like stars can have planets more massive than 4 Jupiter masses between 20 and 100 AU, at 68% confidence. When I include null results from other direct imaging surveys, these constraints are further strengthened: at 68% confidence, fewer than 20% of sun-like stars can have planets more massive than 4 Jupiter masses, at orbital semi-major axes between 8.1 and 911 AU. Even when applying the mass scaling of Johnson et al. (2007), and the "cold start" planet luminosity models of Fortney et al. (2008), the results remain consistent: giant planets are rare at large separations around sun-like stars. I explain how these constraints and planet simulations were used to design the Gemini South NICI Planet-Finding Campaign survey and target list, in order to maximize the chance of NICI detecting a planet, and so giving the campaign the greatest ability to strongly constrain populations of extrasolar giant planets, even in the case of a null result. Finally, I discuss future directions for direct imaging planet searches, and the steps needed tomove fromexisting surveys to a truly unified distribution of extrasolar planet populations.en_US
dc.typeElectronic Dissertationen_US
dc.typetexten_US
thesis.degree.namePh.D.en_US
thesis.degree.leveldoctoralen_US
thesis.degree.disciplineGraduate Collegeen_US
thesis.degree.disciplineAstronomyen_US
thesis.degree.grantorUniversity of Arizonaen_US
dc.contributor.advisorClose, Laird M.en_US
dc.contributor.committeememberClose, Laird M.en_US
dc.contributor.committeememberHinz, Philipen_US
dc.contributor.committeememberMcCarthy, Donen_US
dc.identifier.proquest11518-
dc.identifier.oclc752261381-
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