Show simple item record

Files in this item

Thumbnail

Item metadata

dc.contributor.authorVidotto, Aline
dc.contributor.authorFares, Rim
dc.contributor.authorJardine, Moira Mary
dc.contributor.authorDonati, J.-F.
dc.contributor.authorOpher, M.
dc.contributor.authorMoutou, C.
dc.contributor.authorCatala, C.
dc.contributor.authorGombosi, T. I.
dc.date.accessioned2012-11-18T02:14:32Z
dc.date.available2012-11-18T02:14:32Z
dc.date.issued2012-07-11
dc.identifier.citationVidotto , A , Fares , R , Jardine , M M , Donati , J-F , Opher , M , Moutou , C , Catala , C & Gombosi , T I 2012 , ' The stellar wind cycles and planetary radio emission of the τ Boo system ' , Monthly Notices of the Royal Astronomical Society , vol. 423 , no. 4 , pp. 3285-3298 . https://doi.org/10.1111/j.1365-2966.2012.21122.xen
dc.identifier.issn0035-8711
dc.identifier.otherPURE: 25116538
dc.identifier.otherPURE UUID: 81deede9-1493-4c71-a133-530a1b065a57
dc.identifier.otherArXiv: http://arxiv.org/abs/1204.3843v1
dc.identifier.otherScopus: 84863620539
dc.identifier.otherWOS: 000306003600021
dc.identifier.otherORCID: /0000-0002-1466-5236/work/57821848
dc.identifier.urihttps://hdl.handle.net/10023/3256
dc.description15 pages, 10 figuresen
dc.description.abstractTau Boo is an intriguing planet-host star that is believed to undergo magnetic cycles similar to the Sun, but with a duration that is about one order of magnitude smaller than that of the solar cycle. With the use of observationally derived surface magnetic field maps, we simulate the magnetic stellar wind of Tau Boo by means of three-dimensional MHD numerical simulations. As the properties of the stellar wind depend on the particular characteristics of the stellar magnetic field, we show that the wind varies during the observed epochs of the cycle. Although the mass loss-rates we find (~2.7×10-12 Msun/yr-1) vary less than 3 per cent during the observed epochs of the cycle, our derived angular momentum loss-rates vary from 1.1 to 2.2×1032erg. The spin-down times associated to magnetic braking range between 39 and 78Gyr. We also compute the emission measure from the (quiescent) closed corona and show that it remains approximately constant through these epochs at a value of ~1050.6 cm-3. This suggests that a magnetic cycle of Tau Boo may not be detected by X-ray observations. We further investigate the interaction between the stellar wind and the planet by estimating radio emission from the hot-Jupiter that orbits at 0.0462 au from Tau Boo. By adopting reasonable hypotheses, we show that, for a planet with a magnetic field similar to Jupiter (~14G at the pole), the radio flux is estimated to be about 0.5-1 mJy, occurring at a frequency of 34MHz. If the planet is less magnetised (field strengths roughly Earths ionospheric cutoff. According to our estimates, if the planet is more magnetised than that and provided the emission beam crosses the observer line-of-sight, detection of radio emission from Tau Boo b is only possible by ground-based instruments with a noise level of ≤ 1 mJy, operating at low frequencies.
dc.format.extent14
dc.language.isoeng
dc.relation.ispartofMonthly Notices of the Royal Astronomical Societyen
dc.rightsThis is an author version of the article © 2012 The Authors Monthly Notices of the Royal Astronomical Society. The definitive version (c) 2012 RAS is available at www.blackwell-synergy.comen
dc.subjectMHDen
dc.subjectMethods: Numericalen
dc.subjectStars: individual: Tau Bootisen
dc.subjectStars: magnetic fielden
dc.subjectStars: winds, outflowsen
dc.subjectRadio continuum: planetary systemsen
dc.subjectQB Astronomyen
dc.subject.lccQBen
dc.titleThe stellar wind cycles and planetary radio emission of the τ Boo systemen
dc.typeJournal articleen
dc.contributor.sponsorScience & Technology Facilities Councilen
dc.description.versionPostprinten
dc.contributor.institutionUniversity of St Andrews. School of Physics and Astronomyen
dc.identifier.doihttps://doi.org/10.1111/j.1365-2966.2012.21122.x
dc.description.statusPeer revieweden
dc.date.embargoedUntil2012-11-18
dc.identifier.urlhttp://arxiv.org/abs/1204.3843v1en
dc.identifier.grantnumberST/J001651/1en


This item appears in the following Collection(s)

Show simple item record