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dc.contributor.authorJackson, Brian
dc.contributor.authorArras, Phil
dc.contributor.authorPenev, K.
dc.contributor.authorPeacock, Sarah
dc.contributor.authorMarchant, Pablo
dc.date.accessioned2017-06-23T23:31:36Z
dc.date.available2017-06-23T23:31:36Z
dc.date.issued2017-01-24
dc.identifier.citationA New Model of Roche Lobe Overflow for Short-period Gaseous Planets and Binary Stars 2017, 835 (2):145 The Astrophysical Journalen
dc.identifier.issn1538-4357
dc.identifier.doi10.3847/1538-4357/835/2/145
dc.identifier.urihttp://hdl.handle.net/10150/624385
dc.description.abstractSome close-in gaseous exoplanets are nearly in Roche lobe contact, and previous studies show that tidal decay can drive hot Jupiters into contact during the main sequence of their host stars. Improving on a previous model, we present a revised model for mass transfer in a semidetached binary system that incorporates an extended atmosphere around the donor and allows for an arbitrary mass ratio. We apply this new formalism to hypothetical, confirmed, and candidate planetary systems to estimate mass-loss rates and compare with models of evaporative mass loss. Overflow may be significant for hot Neptunes out to periods of similar to 2 days, while for hot Jupiters, it may only be important inward of 0.5 days. We find that CoRoT-24 b may be losing mass at a rate of more than an Earth mass in a gigayear. The hot Jupiter WASP-12 b may lose an Earth mass in a megayear, while the putative planet PTFO8-8695 orbiting a T Tauri star might shed its atmosphere in a few megayears. We point out that the orbital expansion that can accompany mass transfer may be less effective than previously considered because the gas accreted by the host star removes some of the angular momentum from the orbit, but simple scaling arguments suggest that the Roche lobe overflow might remain stable. Consequently, the recently discovered small planets in ultrashort periods (< 1 day) may not be the remnants of hot Jupiters/Neptunes. The new model presented here has been incorporated into Modules for Experiments in Stellar Astrophysics (MESA).
dc.description.sponsorshipNASA [NAS5-26555]; NASA Office of Space Science [NNX13AC07G]; NASA Science Mission directorate; NASA Grant [NNX13AQ62G]; NASA Origins Grant [NNX14AE16G]; NASA ATP grant [NNH12ZDA]en
dc.language.isoenen
dc.publisherIOP PUBLISHING LTDen
dc.relation.urlhttp://stacks.iop.org/0004-637X/835/i=2/a=145?key=crossref.94358715f8518a0780c563b3d8206c5een
dc.rights© 2017. The American Astronomical Society. All rights reserved.en
dc.subjectbinaries: closeen
dc.subjectplanet-star interactionsen
dc.subjectplanets and satellites: gaseous planetsen
dc.subjectplanets and satellites: individual (CoRoT-24 b, WASP-12 b, PTFO8-8695)en
dc.titleA New Model of Roche Lobe Overflow for Short-period Gaseous Planets and Binary Starsen
dc.typeArticleen
dc.contributor.departmentUniv Arizona, Lunar & Planetary Laben
dc.identifier.journalThe Astrophysical Journalen
dc.description.collectioninformationThis item from the UA Faculty Publications collection is made available by the University of Arizona with support from the University of Arizona Libraries. If you have questions, please contact us at repository@u.library.arizona.edu.en
dc.eprint.versionFinal published versionen
refterms.dateFOA2018-06-28T00:16:24Z
html.description.abstractSome close-in gaseous exoplanets are nearly in Roche lobe contact, and previous studies show that tidal decay can drive hot Jupiters into contact during the main sequence of their host stars. Improving on a previous model, we present a revised model for mass transfer in a semidetached binary system that incorporates an extended atmosphere around the donor and allows for an arbitrary mass ratio. We apply this new formalism to hypothetical, confirmed, and candidate planetary systems to estimate mass-loss rates and compare with models of evaporative mass loss. Overflow may be significant for hot Neptunes out to periods of similar to 2 days, while for hot Jupiters, it may only be important inward of 0.5 days. We find that CoRoT-24 b may be losing mass at a rate of more than an Earth mass in a gigayear. The hot Jupiter WASP-12 b may lose an Earth mass in a megayear, while the putative planet PTFO8-8695 orbiting a T Tauri star might shed its atmosphere in a few megayears. We point out that the orbital expansion that can accompany mass transfer may be less effective than previously considered because the gas accreted by the host star removes some of the angular momentum from the orbit, but simple scaling arguments suggest that the Roche lobe overflow might remain stable. Consequently, the recently discovered small planets in ultrashort periods (< 1 day) may not be the remnants of hot Jupiters/Neptunes. The new model presented here has been incorporated into Modules for Experiments in Stellar Astrophysics (MESA).


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