Exoplanet system Kepler-2 with comparisons to Kepler-1 and 13
dc.authorid | Banks, Timothy/0000-0001-9445-4588 | |
dc.authorid | Puskullu, Caglar/0000-0001-9213-0969 | |
dc.contributor.author | Rhodes, Michael D. | |
dc.contributor.author | Puskullu, Caglar | |
dc.contributor.author | Budding, Edwin | |
dc.contributor.author | Banks, Timothy S. | |
dc.date.accessioned | 2025-01-27T21:00:06Z | |
dc.date.available | 2025-01-27T21:00:06Z | |
dc.date.issued | 2020 | |
dc.department | Çanakkale Onsekiz Mart Üniversitesi | |
dc.description.abstract | We have carried out an intensive study of photometric (Kepler Mission) and spectroscopic data on the system Kepler-2 (HAT-P-7A) using the dedicated software WinFitter 6.4. The mean individual data-point error of the normalized flux values for this system is 0.00015, leading to the model's specification for the mean reference flux to an accuracy of similar to 0.5 ppm. This testifies to the remarkably high accuracy of the binned data-set, derived from over 1.8 million individual observations. Spectroscopic data are reported with the similarly high-accuracy radial velocity amplitude measure of similar to 2 m s(-1). The analysis includes discussion of the fitting quality and model adequacy. Our derived absolute parameters for Kepler-2 are as follows: Mp (Jupiter) 1.80 +/- 0.13; R1.46 +/- 0.08x106 km; Rp km. These values imply somewhat larger and less condensed bodies than previously catalogued, but within reasonable error estimates of such literature parameters. We find also tidal, reflection and Doppler effect parameters, showing that the optimal model specification differs slightly from a 'cleaned' model that reduces the standard deviation of the similar to 3600 binned light curve points to less than 0.9 ppm. We consider these slight differences, making comparisons with the hot-Jupiter systems Kepler-1 (TrES-2) and 13. We confirm that the star's rotation axis must be shifted towards the line of sight, though how closely depends on what rotation velocity is adopted for the star. From joint analysis of the spectroscopic and photometric data we find an equatorial rotation speed of 11 +/- 3 km s(-1). A slightly brighter region of the photosphere that distorts the transit shape can be interpreted as an indication of the gravity effect at the rotation pole; however we note that the geometry for this does not match the spectroscopic result. We discuss this difference, rejecting the possibility that a real shift in the position of the rotation axis in the few years between the spectroscopic and photometric data-collection times.Alternative explanations are considered, but we conclude that renewed detailed observations are required to help settle these questions. | |
dc.description.sponsorship | TUBITAK (Scientific and Technological Research Council of Turkey) [113F353] | |
dc.description.sponsorship | It is a pleasure to thank Prof. Osman Demircan and the colleagues in the Physics Department of COMU (Canakkale, Turkey) for their interest and support of this programme. The research has been supported by TUBITAK (Scientific and Technological Research Council of Turkey) under Grant No. 113F353. Additional help and encouragement for this work has come from the National University of Singapore, particularly through Prof. Lim Tiong Wee of the Department of Statistics and Applied Probability. This research has made use of the NASA Exoplanet Archive, which is operated by the California Institute of Technology, under contract with the National Aeronautics and Space Administration under the Exoplanet Exploration Program. This work has made use of data from the European Space Agency (ESA) mission Gaia (https://www.cosmos.esa.int/gaia), processed by the Gaia Data Processing and Analysis Consortium (DPAC, https://www.cosmos.esa.int/web/gaia/dpac/consortium). TB& EB wish to record our gratitude to the late Prof. Denis J. Sullivan (Victoria University of Wellington, NZ) for his support of this and related programmes, and extend our condolences to his family. | |
dc.identifier.doi | 10.1007/s10509-020-03789-3 | |
dc.identifier.issn | 0004-640X | |
dc.identifier.issn | 1572-946X | |
dc.identifier.issue | 4 | |
dc.identifier.scopus | 2-s2.0-85084146994 | |
dc.identifier.scopusquality | Q2 | |
dc.identifier.uri | https://doi.org/10.1007/s10509-020-03789-3 | |
dc.identifier.uri | https://hdl.handle.net/20.500.12428/26937 | |
dc.identifier.volume | 365 | |
dc.identifier.wos | WOS:000529682500001 | |
dc.identifier.wosquality | Q3 | |
dc.indekslendigikaynak | Web of Science | |
dc.indekslendigikaynak | Scopus | |
dc.language.iso | en | |
dc.publisher | Springer | |
dc.relation.ispartof | Astrophysics and Space Science | |
dc.relation.publicationcategory | info:eu-repo/semantics/openAccess | |
dc.rights | info:eu-repo/semantics/closedAccess | |
dc.snmz | KA_WoS_20250125 | |
dc.subject | Stars - binary | |
dc.subject | Exoplanets | |
dc.subject | Light curve analysis | |
dc.title | Exoplanet system Kepler-2 with comparisons to Kepler-1 and 13 | |
dc.type | Article |