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Michaël Gillon - One of the best experts on this subject based on the ideXlab platform.
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WASP-77 Ab: A Transiting Hot Jupiter Planet in a Wide Binary System
Publications of the Astronomical Society of the Pacific, 2013Co-Authors: Pierre F. L. Maxted, Michaël Gillon, Coel Hellier, A. Collier Cameron, David R. Anderson, A. P. Doyle, A. Fumel, Emmanuel Jehin, Monika Lendl, Francesco PepeAbstract:ABSTRACT.We report the discovery of a transiting Planet with an orbital period of 1.36 days orbiting the brighter component of the visual binary star BD -07 436-07 436. The host star, WASP-77 A, is a moderately bright G8 VV star (V = 10.3V=10.3) with a metallicity close to solar ([Fe/H] = 0.0 ± 0.1[Fe/H]=0.0±0.1). The companion star, WASP-77 B, is a K-dwarf approximately 2 mag fainter at a separation of approximately 3″. The spectrum of WASP-77 A shows emission in the cores of the Caii H and K lines, indicative of moderate chromospheric activity. The Wide Angle Search for Planets (WASP) light curves show photometric variability with a period of 15.3 days and an amplitude of about 0.3% that is probably due to the magnetic activity of the host star. We use an analysis of the combined photometric and spectroscopic data to derive the mass and radius of the Planet (1.76 ± 0.06 MJup1.76±0.06 MJup, 1.21 ± 0.02 RJup1.21±0.02 RJup). The age of WASP-77 A estimated from its rotation rate (∼1 Gyr∼1 Gyr) agrees wi...
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wasp 77 ab a transiting hot Jupiter Planet in a wide binary system
arXiv: Earth and Planetary Astrophysics, 2012Co-Authors: P. F. L. Maxted, Michaël Gillon, D. R. Anderson, A. P. Doyle, A. Fumel, Emmanuel Jehin, Monika Lendl, C Hellier, Collier A Cameron, Francesco PepeAbstract:We report the discovery of a transiting Planet with an orbital period of 1.36d orbiting the brighter component of the visual binary star BD -07 436. The host star, WASP-77A, is a moderately bright G8V star (V=10.3) with a metallicity close to solar ([Fe/H]= 0.0 +- 0.1). The companion star, WASP-77B, is a K-dwarf approximately 2 magnitudes fainter at a separation of approximately 3arcsec. The spectrum of WASP-77A shows emission in the cores of the Ca II H and K lines indicative of moderate chromospheric activity. The WASP lightcurves show photometric variability with a period of 15.3 days and an amplitude of about 0.3% that is probably due to the magnetic activity of the host star. We use an analysis of the combined photometric and spectroscopic data to derive the mass and radius of the Planet (1.76+-0.06MJup, 1.21+-0.02RJup). The age of WASP-77A estimated from its rotation rate (~1 Gyr) agrees with the age estimated in a similar way for WASP-77B (~0.6 Gyr) but is in poor agreement with the age inferred by comparing its effective temperature and density to stellar models (~8 Gyr). Follow-up observations of WASP-77 Ab will make a useful contribution to our understanding of the influence of binarity and host star activity on the properties of hot Jupiters.
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WASP-41b: A transiting hot Jupiter Planet orbiting a magnetically active G8V star
Publications of the Astronomical Society of the Pacific, 2011Co-Authors: Pierre F. L. Maxted, Coel Hellier, A. Collier Cameron, A. H. M. J. Triaud, R. G. West, Barry Smalley, David R. Anderson, Didier Queloz, Rachel Street, Michaël GillonAbstract:ABSTRACT.We report the discovery of a transiting Planet with an orbital period of 3.05 days orbiting the star TYC 7247-587-1. The star, WASP-41, is a moderately bright G8 VV star (V = 11.6V=11.6) with a metallicity close to solar ([Fe/H] = -0.08 ± 0.09[Fe/H]=-0.08±0.09). The star shows evidence of moderate chromospheric activity, both from emission in the cores of the Ca ii H and K ines and photometric variability with a period of 18.4 days and an amplitude of about 1%. We use a new method to show quantitatively that this periodic signal has a low false-alarm probability. The rotation period of the star implies a gyrochronological age for WASP-41 of 1.8 Gyr with an error of about 15%. We have used a combined analysis of the available photometric and spectroscopic data to derive the mass and radius of the Planet (0.92 ± 0.06 MJup0.92±0.06 MJup, 1.20 ± 0.06 RJup1.20±0.06 RJup). Further observations of WASP-41 can be used to explore the connections between the properties of hot Jupiter Planets and the leve...
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Wasp-22 b: A transiting "hot Jupiter" Planet in a hierarchical triple system
The Astronomical Journal, 2010Co-Authors: P. F. L. Maxted, Michaël Gillon, Coel Hellier, D. Queloz, Anderson, Barry Smalley, D. M. Wilson, S. J. Bentley, Heather Cegla, A. H. M. J. TriaudAbstract:We report the discovery of a transiting Planet orbiting the star TYC 6446-326-1. The star, WASP-22, is a moderately bright (V = 12.0) solar-type star (T-eff = 6000 +/- 100 K, [Fe/H]= -0.05 +/- 0.08). The light curve of the star obtained with the WASP-South instrument shows periodic transit-like features with a depth of about 1% and a duration of 0.14 days. The presence of a transit-like feature in the light curve is confirmed using z-band photometry obtained with Faulkes Telescope South. High-resolution spectroscopy obtained with the CORALIE and HARPS spectrographs confirms the presence of a Planetary mass companion with an orbital period of 3.533 days in a near-circular orbit. From a combined analysis of the spectroscopic and photometric data assuming that the star is a typical main-sequence star we estimate that the Planet has a mass M-P = 0.56 +/- 0.02M(Jup) and a radius R-P = 1.12 +/- 0.04R(Jup). In addition, there is a linear trend of 40 m s(-1) yr(-1) in the radial velocities measured over 16 months, from which we infer the presence of a third body with a long-period orbit in this system. The companion may be a low mass M-dwarf, a white dwarf, or a second Planet.
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wasp 22 b a transiting hot Jupiter Planet in a hierarchical triple system
The Astronomical Journal, 2010Co-Authors: P. F. L. Maxted, Michaël Gillon, D. R. Anderson, D. Queloz, B. Smalley, C Hellier, A H M J Triaud, R G West, D. M. WilsonAbstract:We report the discovery of a transiting Planet orbiting the star TYC 6446-326-1. The star, WASP-22, is a moderately bright (V = 12.0) solar-type star (T{sub eff} = 6000 {+-} 100 K, [Fe/H] = -0.05 {+-} 0.08). The light curve of the star obtained with the WASP-South instrument shows periodic transit-like features with a depth of about 1% and a duration of 0.14 days. The presence of a transit-like feature in the light curve is confirmed using z-band photometry obtained with Faulkes Telescope South. High-resolution spectroscopy obtained with the CORALIE and HARPS spectrographs confirms the presence of a Planetary mass companion with an orbital period of 3.533 days in a near-circular orbit. From a combined analysis of the spectroscopic and photometric data assuming that the star is a typical main-sequence star we estimate that the Planet has a mass M{sub p} = 0.56 {+-} 0.02M{sub Jup} and a radius R{sub p} = 1.12 {+-} 0.04R{sub Jup}. In addition, there is a linear trend of 40 m s{sup -1} yr{sup -1} in the radial velocities measured over 16 months, from which we infer the presence of a third body with a long-period orbit in this system. The companion may be amore » low mass M-dwarf, a white dwarf, or a second Planet.« less
Coel Hellier - One of the best experts on this subject based on the ideXlab platform.
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WASP-77 Ab: A Transiting Hot Jupiter Planet in a Wide Binary System
Publications of the Astronomical Society of the Pacific, 2013Co-Authors: Pierre F. L. Maxted, Michaël Gillon, Coel Hellier, A. Collier Cameron, David R. Anderson, A. P. Doyle, A. Fumel, Emmanuel Jehin, Monika Lendl, Francesco PepeAbstract:ABSTRACT.We report the discovery of a transiting Planet with an orbital period of 1.36 days orbiting the brighter component of the visual binary star BD -07 436-07 436. The host star, WASP-77 A, is a moderately bright G8 VV star (V = 10.3V=10.3) with a metallicity close to solar ([Fe/H] = 0.0 ± 0.1[Fe/H]=0.0±0.1). The companion star, WASP-77 B, is a K-dwarf approximately 2 mag fainter at a separation of approximately 3″. The spectrum of WASP-77 A shows emission in the cores of the Caii H and K lines, indicative of moderate chromospheric activity. The Wide Angle Search for Planets (WASP) light curves show photometric variability with a period of 15.3 days and an amplitude of about 0.3% that is probably due to the magnetic activity of the host star. We use an analysis of the combined photometric and spectroscopic data to derive the mass and radius of the Planet (1.76 ± 0.06 MJup1.76±0.06 MJup, 1.21 ± 0.02 RJup1.21±0.02 RJup). The age of WASP-77 A estimated from its rotation rate (∼1 Gyr∼1 Gyr) agrees wi...
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WASP-41b: A transiting hot Jupiter Planet orbiting a magnetically active G8V star
Publications of the Astronomical Society of the Pacific, 2011Co-Authors: Pierre F. L. Maxted, Coel Hellier, A. Collier Cameron, A. H. M. J. Triaud, R. G. West, Barry Smalley, David R. Anderson, Didier Queloz, Rachel Street, Michaël GillonAbstract:ABSTRACT.We report the discovery of a transiting Planet with an orbital period of 3.05 days orbiting the star TYC 7247-587-1. The star, WASP-41, is a moderately bright G8 VV star (V = 11.6V=11.6) with a metallicity close to solar ([Fe/H] = -0.08 ± 0.09[Fe/H]=-0.08±0.09). The star shows evidence of moderate chromospheric activity, both from emission in the cores of the Ca ii H and K ines and photometric variability with a period of 18.4 days and an amplitude of about 1%. We use a new method to show quantitatively that this periodic signal has a low false-alarm probability. The rotation period of the star implies a gyrochronological age for WASP-41 of 1.8 Gyr with an error of about 15%. We have used a combined analysis of the available photometric and spectroscopic data to derive the mass and radius of the Planet (0.92 ± 0.06 MJup0.92±0.06 MJup, 1.20 ± 0.06 RJup1.20±0.06 RJup). Further observations of WASP-41 can be used to explore the connections between the properties of hot Jupiter Planets and the leve...
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Wasp-22 b: A transiting "hot Jupiter" Planet in a hierarchical triple system
The Astronomical Journal, 2010Co-Authors: P. F. L. Maxted, Michaël Gillon, Coel Hellier, D. Queloz, Anderson, Barry Smalley, D. M. Wilson, S. J. Bentley, Heather Cegla, A. H. M. J. TriaudAbstract:We report the discovery of a transiting Planet orbiting the star TYC 6446-326-1. The star, WASP-22, is a moderately bright (V = 12.0) solar-type star (T-eff = 6000 +/- 100 K, [Fe/H]= -0.05 +/- 0.08). The light curve of the star obtained with the WASP-South instrument shows periodic transit-like features with a depth of about 1% and a duration of 0.14 days. The presence of a transit-like feature in the light curve is confirmed using z-band photometry obtained with Faulkes Telescope South. High-resolution spectroscopy obtained with the CORALIE and HARPS spectrographs confirms the presence of a Planetary mass companion with an orbital period of 3.533 days in a near-circular orbit. From a combined analysis of the spectroscopic and photometric data assuming that the star is a typical main-sequence star we estimate that the Planet has a mass M-P = 0.56 +/- 0.02M(Jup) and a radius R-P = 1.12 +/- 0.04R(Jup). In addition, there is a linear trend of 40 m s(-1) yr(-1) in the radial velocities measured over 16 months, from which we infer the presence of a third body with a long-period orbit in this system. The companion may be a low mass M-dwarf, a white dwarf, or a second Planet.
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WASP-32b: A Transiting Hot Jupiter Planet Orbiting a Lithium-Poor, Solar-Type Star
Publications of the Astronomical Society of the Pacific, 2010Co-Authors: Pierre F. L. Maxted, Michaël Gillon, Coel Hellier, A. Collier Cameron, D. Queloz, A. H. M. J. Triaud, R. G. West, Barry Smalley, David R. Anderson, R. EnochAbstract:ABSTRACT. We report the discovery of a transiting Planet orbiting the star TYC 2-1155-1. The star, WASP-32, is a moderately bright (V = 11.3 V = 11.3 ) solar-type star (Teff = 6100 ± 100 K T eff = 6100 ± 100 K , [Fe/H] = -0.13 ± 0.10 [ Fe / H ] = - 0.13 ± 0.10 ). The light curve of the star obtained with the WASP-South and WASP-North instruments shows periodic transitlike features with a depth of about 1% and a duration of 0.10 day every 2.72 days. The presence of a transitlike feature in the light curve is confirmed using z z -band photometry obtained with Faulkes Telescope North. High-resolution spectroscopy obtained with the Coralie spectrograph confirms the presence of a Planetary mass companion. From a combined analysis of the spectroscopic and photometric data, assuming that the star is a typical main-sequence star, we estimate that the Planet has a mass Mp M p of 3.60 ± 0.07 MJup 3.60 ± 0.07 M Jup and a radius Rp = 1.19 ± 0.06 RJup R p = 1.19 ± 0.06 R Jup . WASP-32 is one of a small gro...
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An orbital period of 0.94 days for the hot-Jupiter Planet WASP-18b
Nature, 2009Co-Authors: Coel Hellier, D. R. Anderson, A. Collier Cameron, M. Gillon, L. Hebb, P. F. L. Maxted, D. Queloz, B. Smalley, A. H. M. J. Triaud, R. G. WestAbstract:The ‘hot Jupiters’ that abound in lists of known extrasolar Planets are thought to have formed far from their host stars, but migrate inwards through interactions with the proto-Planetary disk from which they were born^ 1 , 2 , or by an alternative mechanism such as Planet–Planet scattering^ 3 . The hot Jupiters closest to their parent stars, at orbital distances of only ∼0.02 astronomical units, have strong tidal interactions^ 4 , 5 , and systems such as OGLE-TR-56 have been suggested as tests of tidal dissipation theory^ 6 , 7 . Here we report the discovery of Planet WASP-18b with an orbital period of 0.94 days and a mass of ten Jupiter masses (10 M _Jup), resulting in a tidal interaction an order of magnitude stronger than that of Planet OGLE-TR-56b. Under the assumption that the tidal-dissipation parameter Q of the host star is of the order of 10^6, as measured for Solar System bodies and binary stars and as often applied to extrasolar Planets, WASP-18b will be spiralling inwards on a timescale less than a thousandth that of the lifetime of its host star. Therefore either WASP-18 is in a rare, exceptionally short-lived state, or the tidal dissipation in this system (and possibly other hot-Jupiter systems) must be much weaker than in the Solar System. 'Hot Jupiters' abound in lists of known extrasolar Planets. Those closest to their parent stars have strong tidal interactions, leading to the suggestion that systems such as OGLE-TR-56 could be used as tests of tidal dissipation theory. Here, the discovery of Planet WASP-18b is reported, with an orbital period of 0.94 days and a tidal interaction an order of magnitude stronger than that of OGLE-TR-56b. Either WASP-18 is in a rare, short-lived state, or the tidal dissipation in this system must be weaker than in the Solar System. 'Hot Jupiter' extrasolar Planets are thought to have formed at some distance from their host stars and to have migrated inwards at a later date. These Planets provide new perspectives on the evolution of Planetary systems, and the discovery of WASP-18b, the closest-orbiting and most extreme hot Jupiter yet, provides a glimpse of what may be a Planet nearing the end of its life. With a close orbit, high mass (ten times that of Jupiter), and brief (0.94-day) orbital period, WASP-18b has the strongest tidal interaction of any known star–Planet system. We appear to be seeing WASP-18b in a rare and short-lived state as it spirals towards its host star, destined to be destroyed within the host star's lifetime. Alternatively, the tidal dissipation this system — and perhaps other hot Jupiters — must be much weaker than that in our Solar System.
D. Queloz - One of the best experts on this subject based on the ideXlab platform.
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The HARPS search for southern extra-solar Planets - XXXVII. Five new long-period giant Planets and a system update
Astronomy & Astrophysics, 2015Co-Authors: C. Moutou, D. Queloz, Francesco Pepe, François Bouchy, G. Lo Curto, M. Mayor, Willy Benz, C. Lovis, Dominique Naef, Nuno C. SantosAbstract:We describe radial-velocity time series obtained by HARPS on the 3.60 m telescope in La Silla (ESO, Chile) over ten years and report the discovery of five new giant exoPlanets in distant orbits; these new Planets orbit the stars HD 564, HD 30669, HD 108341, and BD -114672. Their periods range from 492 to 1684 days, semi-major axes range from 1.2 to 2.69 AU, and eccentricities range from 0 to 0.85. Their minimum mass ranges from 0.33 to 3.5 M-Jup. We also refine the parameters of two Planets announced previously around HD 113538, based on a longer series of measurements. The Planets have a period of 663 +/- 8 and 1818 +/- 25 days, orbital eccentricities of 0.14 +/- 0.08 and 0.20 +/- 0.04, and minimum masses of 0.36 +/- 0.04 and 0.93 +/- 0.06 M-Jup. Finally, we report the discovery of a new hot-Jupiter Planet around an active star, HD 103720; the Planet has a period of 4.5557 +/- 0.0001 days and a minimum mass of 0.62 +/- 0.025 M-Jup. We discuss the fundamental parameters of these systems and limitations due to stellar activity in quiet stars with typical 2 ms(-1) radial velocity precision.
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XXXVI: Five new long-period giant Planets and a system update
2014Co-Authors: C. Moutou, D. Queloz, G. Lo Curto, M. Mayor, F. Bouchy, Willy Benz, C. Lovis, Dominique Naef, S. G. Sousa, Stéphane UdryAbstract:We describe radial-velocity time series obtained by HARPS on the 3.60 m telescope in La Silla (ESO, Chile) over ten years and report the discovery of five new giant exoPlanets in distant orbits; these new Planets orbit the stars HD 564, HD 30669, HD 108341, and BD-114672. Their periods range from 492 to 1684 days, semi-major axes range from 1.2 to 2.69 AU, and eccentricities range from 0 to 0.85. Their minimum mass ranges from 0.33 to 3.5 MJup. We also refine the parameters of two Planets announced previously around HD 113538, based on a longer series of measurements. The Planets have a period of 663 8 and 1818 25 days, orbital eccentricities of 0.14 0.08 and 0.20 0.04, and minimum masses of 0.36 0.04 and 0.93 0.06 MJup. Finally, we report the discovery of a new hot-Jupiter Planet around an active star, HD 103720; the Planet has a period of 4.5557 0.0001 days and a minimum mass of 0.62 0.025 MJup. We discuss the fundamental parameters of these systems and limitations due to stellar activity in quiet stars with typical 2 m s 1 radial velocity precision.
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Wasp-22 b: A transiting "hot Jupiter" Planet in a hierarchical triple system
The Astronomical Journal, 2010Co-Authors: P. F. L. Maxted, Michaël Gillon, Coel Hellier, D. Queloz, Anderson, Barry Smalley, D. M. Wilson, S. J. Bentley, Heather Cegla, A. H. M. J. TriaudAbstract:We report the discovery of a transiting Planet orbiting the star TYC 6446-326-1. The star, WASP-22, is a moderately bright (V = 12.0) solar-type star (T-eff = 6000 +/- 100 K, [Fe/H]= -0.05 +/- 0.08). The light curve of the star obtained with the WASP-South instrument shows periodic transit-like features with a depth of about 1% and a duration of 0.14 days. The presence of a transit-like feature in the light curve is confirmed using z-band photometry obtained with Faulkes Telescope South. High-resolution spectroscopy obtained with the CORALIE and HARPS spectrographs confirms the presence of a Planetary mass companion with an orbital period of 3.533 days in a near-circular orbit. From a combined analysis of the spectroscopic and photometric data assuming that the star is a typical main-sequence star we estimate that the Planet has a mass M-P = 0.56 +/- 0.02M(Jup) and a radius R-P = 1.12 +/- 0.04R(Jup). In addition, there is a linear trend of 40 m s(-1) yr(-1) in the radial velocities measured over 16 months, from which we infer the presence of a third body with a long-period orbit in this system. The companion may be a low mass M-dwarf, a white dwarf, or a second Planet.
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wasp 22 b a transiting hot Jupiter Planet in a hierarchical triple system
The Astronomical Journal, 2010Co-Authors: P. F. L. Maxted, Michaël Gillon, D. R. Anderson, D. Queloz, B. Smalley, C Hellier, A H M J Triaud, R G West, D. M. WilsonAbstract:We report the discovery of a transiting Planet orbiting the star TYC 6446-326-1. The star, WASP-22, is a moderately bright (V = 12.0) solar-type star (T{sub eff} = 6000 {+-} 100 K, [Fe/H] = -0.05 {+-} 0.08). The light curve of the star obtained with the WASP-South instrument shows periodic transit-like features with a depth of about 1% and a duration of 0.14 days. The presence of a transit-like feature in the light curve is confirmed using z-band photometry obtained with Faulkes Telescope South. High-resolution spectroscopy obtained with the CORALIE and HARPS spectrographs confirms the presence of a Planetary mass companion with an orbital period of 3.533 days in a near-circular orbit. From a combined analysis of the spectroscopic and photometric data assuming that the star is a typical main-sequence star we estimate that the Planet has a mass M{sub p} = 0.56 {+-} 0.02M{sub Jup} and a radius R{sub p} = 1.12 {+-} 0.04R{sub Jup}. In addition, there is a linear trend of 40 m s{sup -1} yr{sup -1} in the radial velocities measured over 16 months, from which we infer the presence of a third body with a long-period orbit in this system. The companion may be amore » low mass M-dwarf, a white dwarf, or a second Planet.« less
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WASP-32b: A Transiting Hot Jupiter Planet Orbiting a Lithium-Poor, Solar-Type Star
Publications of the Astronomical Society of the Pacific, 2010Co-Authors: Pierre F. L. Maxted, Michaël Gillon, Coel Hellier, A. Collier Cameron, D. Queloz, A. H. M. J. Triaud, R. G. West, Barry Smalley, David R. Anderson, R. EnochAbstract:ABSTRACT. We report the discovery of a transiting Planet orbiting the star TYC 2-1155-1. The star, WASP-32, is a moderately bright (V = 11.3 V = 11.3 ) solar-type star (Teff = 6100 ± 100 K T eff = 6100 ± 100 K , [Fe/H] = -0.13 ± 0.10 [ Fe / H ] = - 0.13 ± 0.10 ). The light curve of the star obtained with the WASP-South and WASP-North instruments shows periodic transitlike features with a depth of about 1% and a duration of 0.10 day every 2.72 days. The presence of a transitlike feature in the light curve is confirmed using z z -band photometry obtained with Faulkes Telescope North. High-resolution spectroscopy obtained with the Coralie spectrograph confirms the presence of a Planetary mass companion. From a combined analysis of the spectroscopic and photometric data, assuming that the star is a typical main-sequence star, we estimate that the Planet has a mass Mp M p of 3.60 ± 0.07 MJup 3.60 ± 0.07 M Jup and a radius Rp = 1.19 ± 0.06 RJup R p = 1.19 ± 0.06 R Jup . WASP-32 is one of a small gro...
Pierre F. L. Maxted - One of the best experts on this subject based on the ideXlab platform.
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WASP-77 Ab: A Transiting Hot Jupiter Planet in a Wide Binary System
Publications of the Astronomical Society of the Pacific, 2013Co-Authors: Pierre F. L. Maxted, Michaël Gillon, Coel Hellier, A. Collier Cameron, David R. Anderson, A. P. Doyle, A. Fumel, Emmanuel Jehin, Monika Lendl, Francesco PepeAbstract:ABSTRACT.We report the discovery of a transiting Planet with an orbital period of 1.36 days orbiting the brighter component of the visual binary star BD -07 436-07 436. The host star, WASP-77 A, is a moderately bright G8 VV star (V = 10.3V=10.3) with a metallicity close to solar ([Fe/H] = 0.0 ± 0.1[Fe/H]=0.0±0.1). The companion star, WASP-77 B, is a K-dwarf approximately 2 mag fainter at a separation of approximately 3″. The spectrum of WASP-77 A shows emission in the cores of the Caii H and K lines, indicative of moderate chromospheric activity. The Wide Angle Search for Planets (WASP) light curves show photometric variability with a period of 15.3 days and an amplitude of about 0.3% that is probably due to the magnetic activity of the host star. We use an analysis of the combined photometric and spectroscopic data to derive the mass and radius of the Planet (1.76 ± 0.06 MJup1.76±0.06 MJup, 1.21 ± 0.02 RJup1.21±0.02 RJup). The age of WASP-77 A estimated from its rotation rate (∼1 Gyr∼1 Gyr) agrees wi...
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WASP-41b: A transiting hot Jupiter Planet orbiting a magnetically active G8V star
Publications of the Astronomical Society of the Pacific, 2011Co-Authors: Pierre F. L. Maxted, Coel Hellier, A. Collier Cameron, A. H. M. J. Triaud, R. G. West, Barry Smalley, David R. Anderson, Didier Queloz, Rachel Street, Michaël GillonAbstract:ABSTRACT.We report the discovery of a transiting Planet with an orbital period of 3.05 days orbiting the star TYC 7247-587-1. The star, WASP-41, is a moderately bright G8 VV star (V = 11.6V=11.6) with a metallicity close to solar ([Fe/H] = -0.08 ± 0.09[Fe/H]=-0.08±0.09). The star shows evidence of moderate chromospheric activity, both from emission in the cores of the Ca ii H and K ines and photometric variability with a period of 18.4 days and an amplitude of about 1%. We use a new method to show quantitatively that this periodic signal has a low false-alarm probability. The rotation period of the star implies a gyrochronological age for WASP-41 of 1.8 Gyr with an error of about 15%. We have used a combined analysis of the available photometric and spectroscopic data to derive the mass and radius of the Planet (0.92 ± 0.06 MJup0.92±0.06 MJup, 1.20 ± 0.06 RJup1.20±0.06 RJup). Further observations of WASP-41 can be used to explore the connections between the properties of hot Jupiter Planets and the leve...
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WASP-32b: A Transiting Hot Jupiter Planet Orbiting a Lithium-Poor, Solar-Type Star
Publications of the Astronomical Society of the Pacific, 2010Co-Authors: Pierre F. L. Maxted, Michaël Gillon, Coel Hellier, A. Collier Cameron, D. Queloz, A. H. M. J. Triaud, R. G. West, Barry Smalley, David R. Anderson, R. EnochAbstract:ABSTRACT. We report the discovery of a transiting Planet orbiting the star TYC 2-1155-1. The star, WASP-32, is a moderately bright (V = 11.3 V = 11.3 ) solar-type star (Teff = 6100 ± 100 K T eff = 6100 ± 100 K , [Fe/H] = -0.13 ± 0.10 [ Fe / H ] = - 0.13 ± 0.10 ). The light curve of the star obtained with the WASP-South and WASP-North instruments shows periodic transitlike features with a depth of about 1% and a duration of 0.10 day every 2.72 days. The presence of a transitlike feature in the light curve is confirmed using z z -band photometry obtained with Faulkes Telescope North. High-resolution spectroscopy obtained with the Coralie spectrograph confirms the presence of a Planetary mass companion. From a combined analysis of the spectroscopic and photometric data, assuming that the star is a typical main-sequence star, we estimate that the Planet has a mass Mp M p of 3.60 ± 0.07 MJup 3.60 ± 0.07 M Jup and a radius Rp = 1.19 ± 0.06 RJup R p = 1.19 ± 0.06 R Jup . WASP-32 is one of a small gro...
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An orbital period of 0.94 days for the hot-Jupiter Planet WASP-18b
Nature, 2009Co-Authors: Coel Hellier, Michaël Gillon, A. Collier Cameron, L. Hebb, D. Queloz, A. H. M. J. Triaud, Barry Smalley, Pierre F. L. Maxted, David R. Anderson, R. G. WestAbstract:The 'hot Jupiters' that abound in lists of known extrasolar Planets are thought to have formed far from their host stars, but migrate inwards through interactions with the proto-Planetary disk from which they were born, or by an alternative mechanism such as Planet-Planet scattering. The hot Jupiters closest to their parent stars, at orbital distances of only approximately 0.02 astronomical units, have strong tidal interactions, and systems such as OGLE-TR-56 have been suggested as tests of tidal dissipation theory. Here we report the discovery of Planet WASP-18b with an orbital period of 0.94 days and a mass of ten Jupiter masses (10 M(Jup)), resulting in a tidal interaction an order of magnitude stronger than that of Planet OGLE-TR-56b. Under the assumption that the tidal-dissipation parameter Q of the host star is of the order of 10(6), as measured for Solar System bodies and binary stars and as often applied to extrasolar Planets, WASP-18b will be spiralling inwards on a timescale less than a thousandth that of the lifetime of its host star. Therefore either WASP-18 is in a rare, exceptionally short-lived state, or the tidal dissipation in this system (and possibly other hot-Jupiter systems) must be much weaker than in the Solar System.
A. H. M. J. Triaud - One of the best experts on this subject based on the ideXlab platform.
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WASP-41b: A transiting hot Jupiter Planet orbiting a magnetically active G8V star
Publications of the Astronomical Society of the Pacific, 2011Co-Authors: Pierre F. L. Maxted, Coel Hellier, A. Collier Cameron, A. H. M. J. Triaud, R. G. West, Barry Smalley, David R. Anderson, Didier Queloz, Rachel Street, Michaël GillonAbstract:ABSTRACT.We report the discovery of a transiting Planet with an orbital period of 3.05 days orbiting the star TYC 7247-587-1. The star, WASP-41, is a moderately bright G8 VV star (V = 11.6V=11.6) with a metallicity close to solar ([Fe/H] = -0.08 ± 0.09[Fe/H]=-0.08±0.09). The star shows evidence of moderate chromospheric activity, both from emission in the cores of the Ca ii H and K ines and photometric variability with a period of 18.4 days and an amplitude of about 1%. We use a new method to show quantitatively that this periodic signal has a low false-alarm probability. The rotation period of the star implies a gyrochronological age for WASP-41 of 1.8 Gyr with an error of about 15%. We have used a combined analysis of the available photometric and spectroscopic data to derive the mass and radius of the Planet (0.92 ± 0.06 MJup0.92±0.06 MJup, 1.20 ± 0.06 RJup1.20±0.06 RJup). Further observations of WASP-41 can be used to explore the connections between the properties of hot Jupiter Planets and the leve...
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Wasp-22 b: A transiting "hot Jupiter" Planet in a hierarchical triple system
The Astronomical Journal, 2010Co-Authors: P. F. L. Maxted, Michaël Gillon, Coel Hellier, D. Queloz, Anderson, Barry Smalley, D. M. Wilson, S. J. Bentley, Heather Cegla, A. H. M. J. TriaudAbstract:We report the discovery of a transiting Planet orbiting the star TYC 6446-326-1. The star, WASP-22, is a moderately bright (V = 12.0) solar-type star (T-eff = 6000 +/- 100 K, [Fe/H]= -0.05 +/- 0.08). The light curve of the star obtained with the WASP-South instrument shows periodic transit-like features with a depth of about 1% and a duration of 0.14 days. The presence of a transit-like feature in the light curve is confirmed using z-band photometry obtained with Faulkes Telescope South. High-resolution spectroscopy obtained with the CORALIE and HARPS spectrographs confirms the presence of a Planetary mass companion with an orbital period of 3.533 days in a near-circular orbit. From a combined analysis of the spectroscopic and photometric data assuming that the star is a typical main-sequence star we estimate that the Planet has a mass M-P = 0.56 +/- 0.02M(Jup) and a radius R-P = 1.12 +/- 0.04R(Jup). In addition, there is a linear trend of 40 m s(-1) yr(-1) in the radial velocities measured over 16 months, from which we infer the presence of a third body with a long-period orbit in this system. The companion may be a low mass M-dwarf, a white dwarf, or a second Planet.
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WASP-32b: A Transiting Hot Jupiter Planet Orbiting a Lithium-Poor, Solar-Type Star
Publications of the Astronomical Society of the Pacific, 2010Co-Authors: Pierre F. L. Maxted, Michaël Gillon, Coel Hellier, A. Collier Cameron, D. Queloz, A. H. M. J. Triaud, R. G. West, Barry Smalley, David R. Anderson, R. EnochAbstract:ABSTRACT. We report the discovery of a transiting Planet orbiting the star TYC 2-1155-1. The star, WASP-32, is a moderately bright (V = 11.3 V = 11.3 ) solar-type star (Teff = 6100 ± 100 K T eff = 6100 ± 100 K , [Fe/H] = -0.13 ± 0.10 [ Fe / H ] = - 0.13 ± 0.10 ). The light curve of the star obtained with the WASP-South and WASP-North instruments shows periodic transitlike features with a depth of about 1% and a duration of 0.10 day every 2.72 days. The presence of a transitlike feature in the light curve is confirmed using z z -band photometry obtained with Faulkes Telescope North. High-resolution spectroscopy obtained with the Coralie spectrograph confirms the presence of a Planetary mass companion. From a combined analysis of the spectroscopic and photometric data, assuming that the star is a typical main-sequence star, we estimate that the Planet has a mass Mp M p of 3.60 ± 0.07 MJup 3.60 ± 0.07 M Jup and a radius Rp = 1.19 ± 0.06 RJup R p = 1.19 ± 0.06 R Jup . WASP-32 is one of a small gro...
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An orbital period of 0.94 days for the hot-Jupiter Planet WASP-18b
Nature, 2009Co-Authors: Coel Hellier, D. R. Anderson, A. Collier Cameron, M. Gillon, L. Hebb, P. F. L. Maxted, D. Queloz, B. Smalley, A. H. M. J. Triaud, R. G. WestAbstract:The ‘hot Jupiters’ that abound in lists of known extrasolar Planets are thought to have formed far from their host stars, but migrate inwards through interactions with the proto-Planetary disk from which they were born^ 1 , 2 , or by an alternative mechanism such as Planet–Planet scattering^ 3 . The hot Jupiters closest to their parent stars, at orbital distances of only ∼0.02 astronomical units, have strong tidal interactions^ 4 , 5 , and systems such as OGLE-TR-56 have been suggested as tests of tidal dissipation theory^ 6 , 7 . Here we report the discovery of Planet WASP-18b with an orbital period of 0.94 days and a mass of ten Jupiter masses (10 M _Jup), resulting in a tidal interaction an order of magnitude stronger than that of Planet OGLE-TR-56b. Under the assumption that the tidal-dissipation parameter Q of the host star is of the order of 10^6, as measured for Solar System bodies and binary stars and as often applied to extrasolar Planets, WASP-18b will be spiralling inwards on a timescale less than a thousandth that of the lifetime of its host star. Therefore either WASP-18 is in a rare, exceptionally short-lived state, or the tidal dissipation in this system (and possibly other hot-Jupiter systems) must be much weaker than in the Solar System. 'Hot Jupiters' abound in lists of known extrasolar Planets. Those closest to their parent stars have strong tidal interactions, leading to the suggestion that systems such as OGLE-TR-56 could be used as tests of tidal dissipation theory. Here, the discovery of Planet WASP-18b is reported, with an orbital period of 0.94 days and a tidal interaction an order of magnitude stronger than that of OGLE-TR-56b. Either WASP-18 is in a rare, short-lived state, or the tidal dissipation in this system must be weaker than in the Solar System. 'Hot Jupiter' extrasolar Planets are thought to have formed at some distance from their host stars and to have migrated inwards at a later date. These Planets provide new perspectives on the evolution of Planetary systems, and the discovery of WASP-18b, the closest-orbiting and most extreme hot Jupiter yet, provides a glimpse of what may be a Planet nearing the end of its life. With a close orbit, high mass (ten times that of Jupiter), and brief (0.94-day) orbital period, WASP-18b has the strongest tidal interaction of any known star–Planet system. We appear to be seeing WASP-18b in a rare and short-lived state as it spirals towards its host star, destined to be destroyed within the host star's lifetime. Alternatively, the tidal dissipation this system — and perhaps other hot Jupiters — must be much weaker than that in our Solar System.
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An orbital period of 0.94 days for the hot-Jupiter Planet WASP-18b
Nature, 2009Co-Authors: Coel Hellier, Michaël Gillon, A. Collier Cameron, L. Hebb, D. Queloz, A. H. M. J. Triaud, Barry Smalley, Pierre F. L. Maxted, David R. Anderson, R. G. WestAbstract:The 'hot Jupiters' that abound in lists of known extrasolar Planets are thought to have formed far from their host stars, but migrate inwards through interactions with the proto-Planetary disk from which they were born, or by an alternative mechanism such as Planet-Planet scattering. The hot Jupiters closest to their parent stars, at orbital distances of only approximately 0.02 astronomical units, have strong tidal interactions, and systems such as OGLE-TR-56 have been suggested as tests of tidal dissipation theory. Here we report the discovery of Planet WASP-18b with an orbital period of 0.94 days and a mass of ten Jupiter masses (10 M(Jup)), resulting in a tidal interaction an order of magnitude stronger than that of Planet OGLE-TR-56b. Under the assumption that the tidal-dissipation parameter Q of the host star is of the order of 10(6), as measured for Solar System bodies and binary stars and as often applied to extrasolar Planets, WASP-18b will be spiralling inwards on a timescale less than a thousandth that of the lifetime of its host star. Therefore either WASP-18 is in a rare, exceptionally short-lived state, or the tidal dissipation in this system (and possibly other hot-Jupiter systems) must be much weaker than in the Solar System.
