References of "Smalley, B"
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See detailSpectroscopic survey of Kepler stars. I. HERMES/Mercator observations of A- and F-type stars
Niemczura, E.; Murphy, S. J.; Smalley, B. et al

in Monthly Notices of the Royal Astronomical Society (2015), 450

The Kepler space mission provided near-continuous and high-precision photometry of about 207,000 stars, which can be used for asteroseismology. However, for successful seismic modelling it is equally ... [more ▼]

The Kepler space mission provided near-continuous and high-precision photometry of about 207,000 stars, which can be used for asteroseismology. However, for successful seismic modelling it is equally important to have accurate stellar physical parameters. Therefore, supplementary ground-based data are needed. We report the results of the analysis of high-resolution spectroscopic data of A- and F-type stars from the Kepler field, which were obtained with the HERMES spectrograph on the Mercator telescope. We determined spectral types, atmospheric parameters and chemical abundances for a sample of 117 stars. Hydrogen Balmer, Fe I, and Fe II lines were used to derive effective temperatures, surface gravities, and microturbulent velocities. We determined chemical abundances and projected rotational velocities using a spectrum synthesis technique. The atmospheric parameters obtained were compared with those from the Kepler Input Catalogue (KIC), confirming that the KIC effective temperatures are underestimated for A stars. Effective temperatures calculated by spectral energy distribution fitting are in good agreement with those determined from the spectral line analysis. The analysed sample comprises stars with approximately solar chemical abundances, as well as chemically peculiar stars of the Am, Ap, and Lambda Boo types. The distribution of the projected rotational velocity, Vsini, is typical for A and F stars and ranges from 8 to about 280 km/s, with a mean of 134 km/s. [less ▲]

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See detailWASP-121 b: a hot Jupiter in a polar orbit and close to tidal disruption
Delrez, Laetitia ULg; Santerne, A.; Almenara, J.-M. et al

E-print/Working paper (2015)

We present the discovery by the WASP-South survey, in close collaboration with the Euler and TRAPPIST telescopes, of WASP-121 b, a new remarkable short-period transiting hot Jupiter, whose planetary ... [more ▼]

We present the discovery by the WASP-South survey, in close collaboration with the Euler and TRAPPIST telescopes, of WASP-121 b, a new remarkable short-period transiting hot Jupiter, whose planetary nature has been statistically validated by the PASTIS software. The planet has a mass of 1.183+0.064−0.062 MJup, a radius of 1.865 ± 0.044 RJup, and transits every 1.2749255+0.0000020−0.0000025 days an active F6-type main-sequence star (V=10.4, 1.353+0.080−0.079 M⊙, 1.458 ± 0.030 R⊙, Teff = 6460 ± 140 K). A notable property of WASP-121 b is that its orbital semi-major axis is only ∼1.15 times larger than its Roche limit, which suggests that the planet might be close to tidal disruption. Furthermore, its large size and extreme irradiation (∼7.1 10^9 erg s−1cm−2) make it an excellent target for atmospheric studies via secondary eclipse observations. Using the TRAPPIST telescope, we indeed detect its emission in the z′-band at better than ∼4σ, the measured occultation depth being 603 ± 130 ppm. Finally, from a measurement of the Rossiter-McLaughlin effect with the CORALIE spectrograph, we infer a sky-projected spin-orbit angle of 257.8+5.3−5.5 deg. This result indicates a significant misalignment between the spin axis of the host star and the orbital plane of the planet, the planet being in a nearly polar orbit. Such a high misalignment suggests a migration of the planet involving strong dynamical events with a third body. [less ▲]

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See detailDiscovery of WASP-85Ab: a hot Jupiter in a visual binary system
Brown, D. J. A.; Anderson, D. R.; Armstrong, D. J. et al

E-print/Working paper (2014)

We report the discovery of the transiting hot Jupiter exoplanet WASP-85Ab. Using a combined analysis of spectroscopic and photometric data, we determine that the planet orbits its host star every 2.66 ... [more ▼]

We report the discovery of the transiting hot Jupiter exoplanet WASP-85Ab. Using a combined analysis of spectroscopic and photometric data, we determine that the planet orbits its host star every 2.66 days, and has a mass of 1.09+/-0.03 M_Jup and a radius of 1.44+/-0.02 R_Jup. The host star is of G5 spectral type, with magnitude V=11.2, and lies 125+/-80 pc distant. We find stellar parameters of T_eff=5685+/-65 K, super-solar metallicity ([Fe/H]=0.08+/-0.10), M_star=1.04+/-0.07 M_sun and R_star=0.96+/-0.13 R_sun. The system has a K-dwarf binary companion, WASP-85B, at a separation of approximately 1.5". The close proximity of this companion leads to contamination of our photometry, decreasing the apparent transit depth that we account for during our analysis. Without this correction, we find the depth to be 50 percent smaller, the stellar density to be 32 percent smaller, and the planet radius to be 18 percent smaller than the true value. Many of our radial velocity observations are also contaminated; these are disregarded when analysing the system in favour of the uncontaminated HARPS observations, as they have reduced semi-amplitudes that lead to underestimated planetary masses. We find a long-term trend in the binary position angle, indicating a misalignment between the binary and orbital planes. WASP observations of the system show variability with a period of 14.64 days, indicative of rotational modulation caused by stellar activity. Analysis of the Ca ii H+K lines shows strong emission that implies that both binary components are strongly active. We find that the system is likely to be less than a few Gyr old. WASP-85 lies in the field of view of K2 Campaign 1. Long cadence observations of the planet clearly show the planetary transits, along with the signature of stellar variability. Analysis of the K2 data, both long and short cadence, is ongoing. [less ▲]

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See detailWASP-94 A and B planets: hot-Jupiter cousins in a twin-star system
Neveu-VanMalle, M.; Queloz, D.; Anderson, D. R. et al

in Astronomy and Astrophysics (2014), 572

We report the discovery of two hot-Jupiter planets, each orbiting one of the stars of a wide binary system. <ASTROBJ>WASP-94A</ASTROBJ> (<ASTROBJ>2MASS 20550794-3408079</ASTROBJ>) is an F8 type star ... [more ▼]

We report the discovery of two hot-Jupiter planets, each orbiting one of the stars of a wide binary system. <ASTROBJ>WASP-94A</ASTROBJ> (<ASTROBJ>2MASS 20550794-3408079</ASTROBJ>) is an F8 type star hosting a transiting planet with a radius of 1.72 ± 0.06 R<SUB>Jup</SUB>, a mass of 0.452 ± 0.034 M<SUB>Jup</SUB>, and an orbital period of 3.95 days. The Rossiter-McLaughlin effect is clearly detected, and the measured projected spin-orbit angle indicates that the planet occupies a retrograde orbit. <ASTROBJ>WASP-94B</ASTROBJ> (<ASTROBJ>2MASS 20550915-3408078</ASTROBJ>) is an F9 stellar companion at an angular separation of 15'' (projected separation 2700 au), hosting a gas giant with a minimum mass of 0.618 ± 0.028 M<SUB>Jup</SUB> with a period of 2.008 days, detected by Doppler measurements. The orbital planes of the two planets are inclined relative to each other, indicating that at least one of them is inclined relative to the plane of the stellar binary. These hot Jupiters in a binary system bring new insights into the formation of close-in giant planets and the role of stellar multiplicity. The radial-velocity and photometric data used for this work are only available at the CDS via anonymous ftp to <A href="http://cdsarc.u-strasbg.fr">http://cdsarc.u-strasbg.fr</A> (ftp://130.79.128.5) or via <A href="http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/572/A49">http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/572/A49</A> [less ▲]

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See detailThree sub-Jupiter-mass planets: WASP-69b & WASP-84b transit active K dwarfs and WASP-70Ab transits the evolved primary of a G4+K3 binary
Anderson, D. R.; Collier Cameron, A.; Delrez, Laetitia ULg et al

in Monthly Notices of the Royal Astronomical Society (2014), 445(2),

We report the discovery of the transiting exoplanets WASP-69b, WASP-70Ab and WASP-84b, each of which orbits a bright star (V ˜ 10). WASP-69b is a bloated Saturn-mass planet (0.26 MJup, 1.06 RJup) in a 3 ... [more ▼]

We report the discovery of the transiting exoplanets WASP-69b, WASP-70Ab and WASP-84b, each of which orbits a bright star (V ˜ 10). WASP-69b is a bloated Saturn-mass planet (0.26 MJup, 1.06 RJup) in a 3.868-d period around an active, ˜1-Gyr, mid-K dwarf. ROSAT detected X-rays 60±27 arcsec from WASP-69. If the star is the source then the planet could be undergoing mass-loss at a rate of ˜1012 g s-1. This is one to two orders of magnitude higher than the evaporation rate estimated for HD 209458b and HD 189733b, both of which have exhibited anomalously large Lyman alpha absorption during transit. WASP-70Ab is a sub-Jupiter-mass planet (0.59 MJup, 1.16 RJup) in a 3.713-d orbit around the primary of a spatially resolved, 9-10-Gyr, G4+K3 binary, with a separation of 3.3 arcsec (>=800 au). WASP-84b is a sub-Jupiter-mass planet (0.69 MJup, 0.94 RJup) in an 8.523-d orbit around an active, ˜1-Gyr, early-K dwarf. Of the transiting planets discovered from the ground to date, WASP-84b has the third-longest period. For the active stars WASP-69 and WASP-84, we pre-whitened the radial velocities using a low-order harmonic series. We found that this reduced the residual scatter more than did the oft-used method of pre-whitening with a fit between residual radial velocity and bisector span. The system parameters were essentially unaffected by pre-whitening. [less ▲]

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See detailWASP-104b and WASP-106b: two transiting hot Jupiters in 1.75-day and 9.3-day orbits
Smith, A. M. S.; Anderson, D. R.; Armstrong, D. J. et al

in Astronomy and Astrophysics (2014)

We report the discovery from the WASP survey of two exoplanetary systems, each consisting of a Jupiter-sized planet transiting an 11th magnitude (V) main-sequence star. WASP-104b orbits its star in 1.75 d ... [more ▼]

We report the discovery from the WASP survey of two exoplanetary systems, each consisting of a Jupiter-sized planet transiting an 11th magnitude (V) main-sequence star. WASP-104b orbits its star in 1.75 d, whereas WASP-106b has the fourth-longest orbital period of any planet discovered by means of transits observed from the ground, orbiting every 9.29 d. Each planet is more massive than Jupiter (WASP-104b has a mass of 1.27±0.05 MJup, while WASP-106b has a mass of 1.93±0.08 MJup). Both planets are just slightly larger than Jupiter, with radii of 1.14±0.04 and 1.09±0.04 RJup for WASP-104 and WASP-106 respectively. No significant orbital eccentricity is detected in either system, and while this is not surprising in the case of the short-period WASP-104b, it is interesting in the case of WASP-106b, because many otherwise similar planets are known to have eccentric orbits. [less ▲]

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See detailWASP-117b: a 10-day-period Saturn in an eccentric and misaligned orbit
Lendl, Monika ULg; Triaud, A. H. M. J.; Anderson, D. R. et al

in Astronomy and Astrophysics (2014), 568

We report the discovery of WASP-117b, the first planet with a period beyond 10 days found by the WASP survey. The planet has a mass of M_p = 0.2755 (+/-0.0090) M_jup, a radius of R_p = 1.021 (-0.065 +0 ... [more ▼]

We report the discovery of WASP-117b, the first planet with a period beyond 10 days found by the WASP survey. The planet has a mass of M_p = 0.2755 (+/-0.0090) M_jup, a radius of R_p = 1.021 (-0.065 +0.076) R_jup and is in an eccentric (e = 0.302 +/-0.023), 10.02165 +/- 0.00055 d orbit around a main-sequence F9 star. The host star's brightness (V=10.15 mag) makes WASP-117 a good target for follow-up observations, and with a planetary equilibrium temperature of T_eq = 1024 (-26 +30) K and a low planetary density (rho_p = 0.259 (-0.048 +0.054) rho_jup) it is one of the best targets for transmission spectroscopy among planets with periods around 10 days. From a measurement of the Rossiter-McLaughlin effect, we infer a projected angle between the planetary orbit and stellar spin axes of beta = -44 (+/-11) deg, and we further derive an orbital obliquity of psi = 69.5 (+3.6 -3.1) deg. Owing to the large orbital separation, tidal forces causing orbital circularization and realignment of the planetary orbit with the stellar plane are weak, having had little impact on the planetary orbit over the system lifetime. WASP-117b joins a small sample of transiting giant planets with well characterized orbits at periods above ~8 days. [less ▲]

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See detailA window on exoplanet dynamical histories: Rossiter-McLaughlin observations of WASP-13b and WASP-32b
Brothwell, R.D.; Watson, C.A.; Hébrard, G. et al

in Monthly Notices of the Royal Astronomical Society (2014), 440(4), 3392-3401

We present Rossiter-McLaughlin observations of WASP-13b and WASP-32b and determine the sky-projected angle between the normal of the planetary orbit and the stellar rotation axis (lambda). WASP-13b and ... [more ▼]

We present Rossiter-McLaughlin observations of WASP-13b and WASP-32b and determine the sky-projected angle between the normal of the planetary orbit and the stellar rotation axis (lambda). WASP-13b and WASP-32b both have prograde orbits and are consistent with alignment with measured sky-projected angles of lambda =8°^{+13}_{-12} and lambda =-2°^{+17}_{-19}, respectively. Both WASP-13 and WASP-32 have Teff < 6250 K, and therefore, these systems support the general trend that aligned planetary systems are preferentially found orbiting cool host stars. A Lomb-Scargle periodogram analysis was carried out on archival SuperWASP data for both systems. A statistically significant stellar rotation period detection (above 99.9 per cent confidence) was identified for the WASP-32 system with Prot = 11.6 ± 1.0 days. This rotation period is in agreement with the predicted stellar rotation period calculated from the stellar radius, R*, and vsin i if a stellar inclination of i* = 90° is assumed. With the determined rotation period, the true 3D angle between the stellar rotation axis and the planetary orbit, psi, was found to be psi = 11° ± 14°. We conclude with a discussion on the alignment of systems around cool host stars with Teff < 6150 K by calculating the tidal dissipation time-scale. We find that systems with short tidal dissipation time-scales are preferentially aligned and systems with long tidal dissipation time-scales have a broad range of obliquities. [less ▲]

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See detailTransiting hot Jupiters from WASP-South, Euler and TRAPPIST: WASP-95b to WASP-101b
Hellier, Coel; Anderson, D. R.; Collier Cameron, A. et al

in Monthly Notices of the Royal Astronomical Society (2014)

We report the discovery of the transiting exoplanets WASP-95b, WASP-96b, WASP-97b, WASP-98b, WASP-99b, WASP-100b and WASP-101b. All are hot Jupiters with orbital periods in the range 2.1-5.7 d, masses of ... [more ▼]

We report the discovery of the transiting exoplanets WASP-95b, WASP-96b, WASP-97b, WASP-98b, WASP-99b, WASP-100b and WASP-101b. All are hot Jupiters with orbital periods in the range 2.1-5.7 d, masses of 0.5-2.8 MJup and radii of 1.1-1.4 RJup. The orbits of all the planets are compatible with zero eccentricity. WASP-99b produces the shallowest transit yet found by WASP-South, at 0.4 per cent. The host stars are of spectral type F2-G8. Five have metallicities of [Fe/H] from -0.03 to +0.23, while WASP-98 has a metallicity of -0.60, exceptionally low for a star with a transiting exoplanet. Five of the host stars are brighter than V = 10.8, which significantly extends the number of bright transiting systems available for follow-up studies. WASP-95 shows a possible rotational modulation at a period of 20.7 d. We discuss the completeness of WASP survey techniques by comparing to the HATnet project. [less ▲]

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See detailTransiting planets from WASP-South, Euler and TRAPPIST: WASP-68 b, WASP-73 b and WASP-88 b, three hot Jupiters transiting evolved solar-type stars
Delrez, Laetitia ULg; Van Grootel, Valérie ULg; Anderson, D. R. et al

in Astronomy and Astrophysics (2014)

Using the WASP transit survey, we report the discovery of three new hot Jupiters, WASP-68 b, WASP-73 b and WASP-88 b. The planet WASP-68 bhas a mass of 0.95 ± 0.03 MJup, a radius of 1.24-0.06+0.10 RJup ... [more ▼]

Using the WASP transit survey, we report the discovery of three new hot Jupiters, WASP-68 b, WASP-73 b and WASP-88 b. The planet WASP-68 bhas a mass of 0.95 ± 0.03 MJup, a radius of 1.24-0.06+0.10 RJup, and orbits a V = 10.7 G0-type star (1.24 ± 0.03 M&sun; 1.69-0.06+0.11 R&sun;, Teff = 5911 ± 60 K) with a period of 5.084298 ± 0.000015 days. Its size is typical of hot Jupiters with similar masses. The planet WASP-73 bis significantly more massive (1.88-0.06+0.07 MJup) and slightly larger (1.16-0.08+0.12 RJup) than Jupiter. It orbits a V = 10.5 F9-type star (1.34-0.04+0.05 M&sun;, 2.07-0.08+0.19 R&sun;, Teff = 6036 ± 120 K) every 4.08722 ± 0.00022 days. Despite its high irradiation (~2.3 × 109 erg s-1 cm-2), WASP-73 b has a high mean density (1.20-0.30+0.26 rhoJup) that suggests an enrichment of the planet in heavy elements. The planet WASP-88 bis a 0.56 ± 0.08 MJuphot Jupiter orbiting a V = 11.4 F6-type star (1.45 ± 0.05 M&sun;, 2.08-0.06+0.12 R&sun;, Teff = 6431 ± 130 K) with a period of 4.954000 ± 0.000019 days. With a radius of 1.70-0.07+0.13 RJup, it joins the handful of planets with super-inflated radii. The ranges of ages we determine through stellar evolution modeling are 4.5-7.0 Gyr for WASP-68, 2.8-5.7 Gyr for WASP-73 and 1.8-4.3 Gyr for WASP-88. The star WASP-73 appears to be significantly evolved, close to or already in the subgiant phase. The stars WASP-68 and WASP-88 are less evolved, although in an advanced stage of core H-burning. [less ▲]

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See detailSpectroscopic survey of Kepler stars: high-resolution observations of A- and F-type stars
Niemczura, E.; Smalley, B.; Murphy, S. et al

in IAU Symposium (2014, February 01)

Basic stellar parameters such as effective temperature, surface gravity, chemical composition, and projected rotational velocity, are important to classify stars and are crucial for successful ... [more ▼]

Basic stellar parameters such as effective temperature, surface gravity, chemical composition, and projected rotational velocity, are important to classify stars and are crucial for successful asteroseismic modelling. However, the Kepler space data do not provide such information. Therefore, ground-based spectral and multi-colour observations of Kepler asteroseismic targets are necessary to complement the space data. For this purpose, in coordination with the KASC ground-based observational Working Groups, high-resolution spectroscopic data for more than 500 B, A, F and G-type stars were collected. [less ▲]

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See detailWASP-20b and WASP-28b: a hot Saturn and a hot Jupiter in near-aligned orbits around solar-type stars
Anderson, D. R.; Collier Cameron, A.; Hellier, C. et al

E-print/Working paper (2014)

We report the discovery of the planets WASP-20b and WASP-28b along with measurements of their sky-projected orbital obliquities. WASP-20b is an inflated, Saturn-mass planet (0.31 $M_{\rm Jup}$; 1.46 $R ... [more ▼]

We report the discovery of the planets WASP-20b and WASP-28b along with measurements of their sky-projected orbital obliquities. WASP-20b is an inflated, Saturn-mass planet (0.31 $M_{\rm Jup}$; 1.46 $R_{\rm Jup}$) in a 4.9-day, near-aligned ($\lambda = 8.1 \pm 3.6^\circ$) orbit around CD-24 102 ($V$=10.7; F9). WASP-28b is an inflated, Jupiter-mass planet (0.91 $M_{\rm Jup}$; 1.21 $R_{\rm Jup}$) in a 3.4-day, near-aligned ($\lambda = 8 \pm 18^\circ$) orbit around a $V$=12, F8 star. As intermediate-mass planets in short orbits around aged, cool stars ($7^{+2}_{-1}$ Gyr for WASP-20 and $5^{+3}_{-2}$ Gyr for WASP-28; both with $T_{\rm eff}$ < 6250 K), their orbital alignment is consistent with the hypothesis that close-in giant planets are scattered into eccentric orbits with random alignments, which are then circularised and aligned with their stars' spins via tidal dissipation. [less ▲]

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See detailHigh-frequency A-type pulsators discovered using SuperWASP
Holdsworth, Daniel L.; Smalley, B.; Gillon, Michaël ULg et al

in Monthly Notices of the Royal Astronomical Society (2014)

We present the results of a survey using the WASP archive to search for high-frequency pulsations in F-, A- and B-type stars. Over 1.5 million targets have been searched for pulsations with amplitudes ... [more ▼]

We present the results of a survey using the WASP archive to search for high-frequency pulsations in F-, A- and B-type stars. Over 1.5 million targets have been searched for pulsations with amplitudes greater than 0.5 millimagnitude. We identify over 350 stars which pulsate with periods less than 30 min. Spectroscopic follow-up of selected targets has enabled us to confirm 10 new rapidly oscillating Ap stars, 13 pulsating Am stars and the fastest known δ Scuti star. We also observe stars which show pulsations in both the high-frequency domain and the low-frequency δ Scuti range. This work shows the power of the WASP photometric survey to find variable stars with amplitudes well below the nominal photometric precision per observation. [less ▲]

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See detailWASP-103 b: A new planet at the edge of tidal disruption
Gillon, Michaël ULg; Anderson, D. R.; Collier-Cameron, A. et al

in Astronomy and Astrophysics (2014)

We report the discovery of WASP-103b, a new ultra-short-period planet (P=22.2 hr) transiting a 12.1 V-magnitude F8-type main-sequence star (1.22+-0.04 Msun, 1.44-0.03+0.05 Rsun, Teff = 6110+-160 K). WASP ... [more ▼]

We report the discovery of WASP-103b, a new ultra-short-period planet (P=22.2 hr) transiting a 12.1 V-magnitude F8-type main-sequence star (1.22+-0.04 Msun, 1.44-0.03+0.05 Rsun, Teff = 6110+-160 K). WASP-103b is significantly more massive (1.49+-0.09 Mjup) and larger (1.53-0.07+0.05 Rjup) than Jupiter. Its large size and extreme irradiation (around 9 10^9 erg/s/cm^2) make it an exquisite target for a thorough atmospheric characterization with existing facilities. Furthermore, its orbital distance is less than 20% larger than its Roche radius, meaning that it might be significantly distorted by tides and might experience mass loss through Roche-lobe overflow. It thus represents a new key object for understanding the last stage of the tidal evolution of hot Jupiters. [less ▲]

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See detailThree WASP-South transiting exoplanets: WASP-74b, WASP-83b \amp WASP-89b
Hellier, C.; Anderson, D. R.; Collier Cameron, A. et al

E-print/Working paper (2014)

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See detailSix newly-discovered hot Jupiters transiting F/G stars: WASP-87b, WASP-108b, WASP-109b, WASP-110b, WASP-111b \amp WASP-112b
Anderson, D. R.; Brown, D. J. A.; Collier Cameron, A. et al

E-print/Working paper (2014)

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See detailEclipsing Am binary systems in the SuperWASP survey
Smalley, B.; Southworth, J.; Pintado, O. I. et al

in Astronomy and Astrophysics (2014), 564

The results of a search for eclipsing Am star binaries using photometry from the SuperWASP survey are presented. The light curves of 1742 Am stars fainter than V = 8.0 were analysed for the presence of ... [more ▼]

The results of a search for eclipsing Am star binaries using photometry from the SuperWASP survey are presented. The light curves of 1742 Am stars fainter than V = 8.0 were analysed for the presence of eclipses. A total of 70 stars were found to exhibit eclipses, with 66 having sufficient observations to enable orbital periods to be determined and 28 of which are newly identified eclipsing systems. Also presented are spectroscopic orbits for 5 of the systems. The number of systems and the period distribution is found to be consistent with that identified in previous radial velocity surveys of "classical" Am stars. [less ▲]

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See detailWASP-71b: a bloated hot Jupiter in an 2.9-day, prograde orbit around an evolved F8 star
Smith, A. M. S.; Anderson, D. R.; Bouchy, F. et al

in Astronomy and Astrophysics (2013), 552

We report the discovery by the WASP transit survey of a highly-irradiated, massive (2.242 +/- 0.080 MJup) planet which transits a bright (V = 10.6), evolved F8 star every 2.9 days. The planet, WASP-71b ... [more ▼]

We report the discovery by the WASP transit survey of a highly-irradiated, massive (2.242 +/- 0.080 MJup) planet which transits a bright (V = 10.6), evolved F8 star every 2.9 days. The planet, WASP-71b, is larger than Jupiter (1.46 +/- 0.13 RJup), but less dense (0.71 +/- 0.16 {\rho}Jup). We also report spectroscopic observations made during transit with the CORALIE spectrograph, which allow us to make a highly-significant detection of the Rossiter-McLaughlin effect. We determine the sky-projected angle between the stellar-spin and planetary-orbit axes to be {\lambda} = 20.1 +/- 9.7 degrees, i.e. the system is 'aligned', according to the widely-used alignment criteria that systems are regarded as misaligned only when {\lambda} is measured to be greater than 10 degrees with 3-{\sigma} confidence. WASP-71, with an effective temperature of 6059 +/- 98 K, therefore fits the previously observed pattern that only stars hotter than 6250 K are host to planets in misaligned orbits. We emphasise, however, that {\lambda} is merely the sky-projected obliquity angle; we are unable to determine whether the stellar-spin and planetary-orbit axes are misaligned along the line-of-sight. With a mass of 1.56 +/- 0.07 Msun, WASP-71 was previously hotter than 6250 K, and therefore might have been significantly misaligned in the past. If so, the planetary orbit has been realigned, presumably through tidal interactions with the cooling star's growing convective zone. [less ▲]

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See detailDiscovery of WASP-65b and WASP-75b: Two Hot Jupiters Without Highly Inflated Radii
Gómez Maqueo Chew, Y.; Faedi, F.; Pollacco, D. et al

in Astronomy and Astrophysics (2013)

We report the discovery of two transiting hot Jupiters, WASP-65b (Mpl = 1.55 ± 0.16 MJ; Rpl = 1.11 ± 0.06 RJ), and WASP-75b (Mpl = 1.07 ± 0.05 MJ; Rpl = 1.27 ± 0.05 RJ). They orbit their host star every ... [more ▼]

We report the discovery of two transiting hot Jupiters, WASP-65b (Mpl = 1.55 ± 0.16 MJ; Rpl = 1.11 ± 0.06 RJ), and WASP-75b (Mpl = 1.07 ± 0.05 MJ; Rpl = 1.27 ± 0.05 RJ). They orbit their host star every ~2.311, and ~2.484 days, respectively. The planet host WASP-65 is a G6 star (Teff = 5600 K, [Fe/H] = -0.07 ± 0.07, age ≳8 Gyr); WASP-75 is an F9 star (Teff = 6100 K, [Fe/H] = 0.07 ± 0.09, age ~ 3 Gyr). WASP-65b is one of the densest known exoplanets in the mass range 0.1 and 2.0 MJ (rhopl = 1.13 ± 0.08 rhoJ), a mass range where a large fraction of planets are found to be inflated with respect to theoretical planet models. WASP-65b is one of only a handful of planets with masses of ~1.5 MJ, a mass regime surprisingly underrepresented among the currently known hot Jupiters. The radius of WASP-75b is slightly inflated (≲10%) as compared to theoretical planet models with no core, and has a density similar to that of Saturn (rhopl = 0.52 ± 0.06 rhoJ). [less ▲]

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See detailThree irradiated and bloated hot Jupiters: WASP-76b, WASP-82b & WASP-90b
West, R. G.; Almenara, J.-M.; Anderson, D. R. et al

E-print/Working paper (2013)

We report three new transiting hot-Jupiter planets discovered from the WASP surveys combined with radial velocities from OHP/SOPHIE and Euler/CORALIE and photometry from Euler and TRAPPIST. All three ... [more ▼]

We report three new transiting hot-Jupiter planets discovered from the WASP surveys combined with radial velocities from OHP/SOPHIE and Euler/CORALIE and photometry from Euler and TRAPPIST. All three planets are inflated, with radii 1.7-1.8 Rjup. All orbit hot stars, F5-F7, and all three stars have evolved, post-MS radii (1.7-2.2 Rsun). Thus the three planets, with orbits of 1.8-3.9 d, are among the most irradiated planets known. This reinforces the correlation between inflated planets and stellar irradiation. [less ▲]

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