Show simple item record

dc.contributor.advisorEisner, Joshua A.en
dc.contributor.authorSallum, Stephanie Elise
dc.creatorSallum, Stephanie Eliseen
dc.date.accessioned2017-09-27T15:37:21Z
dc.date.available2017-09-27T15:37:21Z
dc.date.issued2017
dc.identifier.urihttp://hdl.handle.net/10150/625645
dc.description.abstractFor decades, astronomers have used observations of mature planetary systems to constrain planet formation theories, beginning with our own solar system and now the thousands of known exoplanets. Recent advances in instrumentation have given us a direct view of some steps in the planet formation process, such as large-scale protostar and protoplanetary disk features and evolution. However, understanding the details of how planets accrete and interact with their environment requires direct observations of protoplanets themselves. Transition disks, protoplanetary disks with inner clearings that may be caused by forming planets, are the best targets for these studies. Their large distances, compared to the stars normally targeted for direct imaging of exoplanets, make protoplanet detection difficult and necessitate novel imaging techniques. In this dissertation, I describe the results of using non-redundant masking (NRM) to search for forming planets in transition disk clearings. I first present a data reduction pipeline that I wrote to this end, using example datasets and simulations to demonstrate reduction and imaging optimizations. I discuss two transition disk NRM case studies: T Cha and LkCa 15. In the case of T Cha, while we detect significant asymmetries, the data cannot be explained by orbiting companions. The fluxes and orbital motion of the LkCa 15 companion signals, however, can be naturally explained by protoplanets in the disk clearing. I use these datasets and simulated observations to illustrate the effects of scattered light from transition disk material on NRM protoplanet searches. I then demonstrate the utility of the dual-aperture Large Binocular Telescope Interferometer's NRM mode on the bright B[e] star MWC 349A. I discuss the implications of this work for planet formation studies as well as future prospects for NRM and related techniques on next generation instruments.
dc.language.isoen_USen
dc.publisherThe University of Arizona.en
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
dc.subjectexoplanetsen
dc.subjecthigh contrast imagingen
dc.subjectinterferometryen
dc.subjectplanet formationen
dc.subjectprotoplanetary disksen
dc.subjecttransition disksen
dc.titleImaging Planet Formation Inside the Diffraction Limiten_US
dc.typetexten
dc.typeElectronic Dissertationen
thesis.degree.grantorUniversity of Arizonaen
thesis.degree.leveldoctoralen
dc.contributor.committeememberEisner, Joshua A.en
dc.contributor.committeememberHinz, Philip M.en
dc.contributor.committeememberClose, Laird M.en
dc.contributor.committeememberGuyon, Olivieren
dc.contributor.committeememberBarman, Travis S.en
dc.contributor.committeememberKratter, Kaitlinen
thesis.degree.disciplineGraduate Collegeen
thesis.degree.disciplineAstronomyen
thesis.degree.namePh.D.en
refterms.dateFOA2018-09-11T23:09:05Z
html.description.abstractFor decades, astronomers have used observations of mature planetary systems to constrain planet formation theories, beginning with our own solar system and now the thousands of known exoplanets. Recent advances in instrumentation have given us a direct view of some steps in the planet formation process, such as large-scale protostar and protoplanetary disk features and evolution. However, understanding the details of how planets accrete and interact with their environment requires direct observations of protoplanets themselves. Transition disks, protoplanetary disks with inner clearings that may be caused by forming planets, are the best targets for these studies. Their large distances, compared to the stars normally targeted for direct imaging of exoplanets, make protoplanet detection difficult and necessitate novel imaging techniques. In this dissertation, I describe the results of using non-redundant masking (NRM) to search for forming planets in transition disk clearings. I first present a data reduction pipeline that I wrote to this end, using example datasets and simulations to demonstrate reduction and imaging optimizations. I discuss two transition disk NRM case studies: T Cha and LkCa 15. In the case of T Cha, while we detect significant asymmetries, the data cannot be explained by orbiting companions. The fluxes and orbital motion of the LkCa 15 companion signals, however, can be naturally explained by protoplanets in the disk clearing. I use these datasets and simulated observations to illustrate the effects of scattered light from transition disk material on NRM protoplanet searches. I then demonstrate the utility of the dual-aperture Large Binocular Telescope Interferometer's NRM mode on the bright B[e] star MWC 349A. I discuss the implications of this work for planet formation studies as well as future prospects for NRM and related techniques on next generation instruments.


Files in this item

Thumbnail
Name:
azu_etd_15777_sip1_m.pdf
Size:
16.55Mb
Format:
PDF

This item appears in the following Collection(s)

Show simple item record