Show simple item record

Files in this item

Thumbnail

Item metadata

dc.contributor.authorScandariato, G.
dc.contributor.authorMaggio, A.
dc.contributor.authorLanza, A. F.
dc.contributor.authorPagano, I.
dc.contributor.authorFares, R.
dc.contributor.authorShkolnik, E. L.
dc.contributor.authorBohlender, D.
dc.contributor.authorCameron, A. C.
dc.contributor.authorDieters, S.
dc.contributor.authorDonati, J.-F.
dc.contributor.authorMartínez Fiorenzano, A. F.
dc.contributor.authorJardine, M.
dc.contributor.authorMoutou, C.
dc.date.accessioned2014-09-23T11:31:01Z
dc.date.available2014-09-23T11:31:01Z
dc.date.issued2013-04
dc.identifier.citationScandariato , G , Maggio , A , Lanza , A F , Pagano , I , Fares , R , Shkolnik , E L , Bohlender , D , Cameron , A C , Dieters , S , Donati , J-F , Martínez Fiorenzano , A F , Jardine , M & Moutou , C 2013 , ' A coordinated optical and X-ray spectroscopic campaign on HD 179949 : searching for planet-induced chromospheric and coronal activity ' , Astronomy & Astrophysics , vol. 552 , A7 . https://doi.org/10.1051/0004-6361/201219875en
dc.identifier.issn0004-6361
dc.identifier.otherPURE: 109848616
dc.identifier.otherPURE UUID: 5bfd4020-7294-4461-87a7-5fc4bdb8d7f0
dc.identifier.otherBibCode: 2013A&A...552A...7S
dc.identifier.otherScopus: 84874848522
dc.identifier.otherORCID: /0000-0002-8863-7828/work/58531308
dc.identifier.otherORCID: /0000-0002-1466-5236/work/57821807
dc.identifier.urihttps://hdl.handle.net/10023/5474
dc.description.abstractContext. HD 179949 is an F8V star, orbited by a close-in giant planet with a period of ~3 days. Previous studies suggested that the planet enhances the magnetic activity of the parent star, producing a chromospheric hot spot which rotates in phase with the planet orbit. However, this phenomenon is intermittent since it was observed in several but not all seasons. Aims. A long-term monitoring of the magnetic activity of HD 179949 is required to study the amplitude and time scales of star-planet interactions. Methods. In 2009 we performed a simultaneous optical and X-ray spectroscopic campaign to monitor the magnetic activity of HD 179949 during ~5 orbital periods and ~2 stellar rotations. We analyzed the Ca II H&K lines as a proxy for chromospheric activity, and we studied the X-ray emission in search of flux modulations and to determine basic properties of the coronal plasma. Results. A detailed analysis of the flux in the cores of the Ca II H&K lines and a similar study of the X-ray photometry shows evidence of source variability, including one flare. The analysis of the time series of chromospheric data indicates a modulation with a ~11 days period, compatible with the stellar rotation period at high latitudes. Instead, the X-ray light curve suggests a signal with a period of ~4 days, consistent with the presence of two active regions on opposite hemispheres. Conclusions. The observed variability can be explained, most likely, as due to rotational modulation and to intrinsic evolution of chromospheric and coronal activity. There is no clear signature related to the orbital motion of the planet, but the possibility that just a fraction of the chromospheric and coronal variability is modulated with the orbital period of the planet, or the stellar-planet beat period, cannot be excluded. We conclude that any effect due to the presence of the planet is difficult to disentangle.
dc.format.extent13
dc.language.isoeng
dc.relation.ispartofAstronomy & Astrophysicsen
dc.rights© ESO, 2013. Reproduced with permission from Astronomy & Astrophysics, © ESOen
dc.subjectPlanet-star interactionsen
dc.subjectStars: activityen
dc.subjectStars: magnetic fielden
dc.subjectStars: solar-typeen
dc.subjectQB Astronomyen
dc.subjectQC Physicsen
dc.subject.lccQBen
dc.subject.lccQCen
dc.titleA coordinated optical and X-ray spectroscopic campaign on HD 179949 : searching for planet-induced chromospheric and coronal activityen
dc.typeJournal articleen
dc.contributor.sponsorScience & Technology Facilities Councilen
dc.contributor.sponsorPPARC - Now STFCen
dc.contributor.sponsorScience & Technology Facilities Councilen
dc.contributor.sponsorScience & Technology Facilities Councilen
dc.contributor.sponsorScience & Technology Facilities Councilen
dc.description.versionPublisher PDFen
dc.contributor.institutionUniversity of St Andrews. School of Physics and Astronomyen
dc.identifier.doihttps://doi.org/10.1051/0004-6361/201219875
dc.description.statusPeer revieweden
dc.identifier.grantnumberST/I000666/1en
dc.identifier.grantnumberPP/D000890/1en
dc.identifier.grantnumberST/J001651/1en
dc.identifier.grantnumberST/G001006/1en
dc.identifier.grantnumberPP/F000065/1en


This item appears in the following Collection(s)

Show simple item record