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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 detailAnalysis of Spin-Orbit Alignment in the WASP-32, WASP-38, and HAT-P-27/WASP-40 Systems
Brown, D. J. A.; Collier Cameron, A.; Díaz, R. F. et al

in Astrophysical Journal (2012), 760

We present measurements of the spin-orbit alignment angle, λ, for the hot Jupiter systems WASP-32, WASP-38, and HAT-P-27/WASP-40, based on data obtained using the HARPS spectrograph. We analyze the ... [more ▼]

We present measurements of the spin-orbit alignment angle, λ, for the hot Jupiter systems WASP-32, WASP-38, and HAT-P-27/WASP-40, based on data obtained using the HARPS spectrograph. We analyze the Rossiter-McLaughlin effect for all three systems and also carry out Doppler tomography for WASP-32 and WASP-38. We find that WASP-32 (T [SUB]eff[/SUB] = 6140[SUP]+90[/SUP] [SUB]- 100[/SUB] K) is aligned, with an alignment angle of λ = 10fdg5[SUP] + 6.4[/SUP] [SUB] - 6.5[/SUB] obtained through tomography, and that WASP-38 (T [SUB]eff[/SUB] = 6180[SUP]+40[/SUP] [SUB]- 60[/SUB] K) is also aligned, with tomographic analysis yielding λ = 7fdg5[SUP] + 4.7[/SUP] [SUB] - 6.1[/SUB]. The latter result provides an order-of-magnitude improvement in the uncertainty in λ compared to the previous analysis of Simpson et al. We are only able to loosely constrain the angle for HAT-P-27/WASP-40 (T [SUB]eff[/SUB] = 5190[SUP]+160[/SUP] [SUB]- 170[/SUB] K) to λ = 24fdg2[SUP] + 76.0[/SUP] [SUB] - 44.5[/SUB], owing to the poor signal-to-noise ratio of our data. We consider this result a non-detection under a slightly updated version of the alignment test of Brown et al. We place our results in the context of the full sample of spin-orbit alignment measurements, finding that they provide further support for previously established trends. Based on observations (under proposal 087.C-0649) made using the HARPS High Resolution Échelle Spectrograph mounted on the ESO 3.6 m at the ESO La Silla observatory. [less ▲]

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See detailRossiter-McLaughlin effect measurements for WASP-16, WASP-25 and WASP-31★
Brown, D J A; Cameron, A Collier; Anderson, D R et al

in Monthly Notices of the Royal Astronomical Society (2012)

We present new measurements of the Rossiter-McLaughlin (RM) effect for three Wide Angle Search for transiting Planets (WASP) planetary systems, WASP-16, WASP-25 and WASP-31, from a combined analysis of ... [more ▼]

We present new measurements of the Rossiter-McLaughlin (RM) effect for three Wide Angle Search for transiting Planets (WASP) planetary systems, WASP-16, WASP-25 and WASP-31, from a combined analysis of their complete sets of photometric and spectroscopic data. We find a low-amplitude RM effect for WASP-16 (T[SUB]eff[/SUB]= 5700 ± 150 K), suggesting that the star is a slow rotator and thus of an advanced age, and obtain a projected alignment angle of ?. For WASP-25 (T[SUB]eff[/SUB]= 5750 ± 100 K), we detect a projected spin-orbit angle of λ= 14°.6 ± 6°.7. WASP-31 (T[SUB]eff[/SUB]= 6300 ± 100 K) is found to be well aligned, with a projected spin-orbit angle of λ= 2°.8 ± 3°.1. A circular orbit is consistent with the data for all three systems, in agreement with their respective discovery papers. We consider the results for these systems in the context of the ensemble of RM measurements made to date. We find that whilst WASP-16 fits the hypothesis of Winn et al. that 'cool' stars (T[SUB]eff[/SUB] < 6250 K) are preferentially aligned, WASP-31 has little impact on the proposed trend. We bring the total distribution of the true spin-orbit alignment angle, ψ, up to date, noting that recent results have improved the agreement with the theory of Fabrycky & Tremaine at mid-range angles. We also suggest a new test for judging misalignment using the Bayesian information criterion, according to which WASP-25 b's orbit should be considered to be aligned. [less ▲]

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See detailWASP-35b, WASP-48b and WASP-51b: Two new planets and an independent discovery of HAT-P-30b
Enoch, B.; Anderson, D. R.; Barros, S. C. C. et al

in Astronomical Journal (The) (2011), 142(3), 86

We report the detection of WASP-35b, a planet transiting a metal-poor ([Fe/H] = -0.15) star in the Southern hemisphere, WASP-48b, an inflated planet which may have spun-up its slightly evolved host star ... [more ▼]

We report the detection of WASP-35b, a planet transiting a metal-poor ([Fe/H] = -0.15) star in the Southern hemisphere, WASP-48b, an inflated planet which may have spun-up its slightly evolved host star of 1.75 R_sun in the Northern hemisphere, and the independent discovery of HAT-P-30b / WASP-51b, a new planet in the Northern hemisphere. Using WASP, RISE, FTS and TRAPPIST photometry, with CORALIE, SOPHIE and NOT spectroscopy, we determine that WASP-35b has a mass of 0.72 +/- 0.06 M_J and radius of 1.32 +/- 0.03 R_J, and orbits with a period of 3.16 days, WASP-48b has a mass of 0.98 +/- 0.09 M_J, radius of 1.67 +/- 0.08 R_J and orbits in 2.14 days, while WASP-51b, with an orbital period of 2.81 days, is found to have a mass of 0.76 +/- 0.05 M_J and radius of 1.42 +/- 0.04 R_J, agreeing with values of 0.71 +/- 0.03 M_J and 1.34 +/- 0.07 R_J reported for HAT-P-30b. [less ▲]

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See detailWASP-50 b: a hot Jupiter transiting a moderately active solar-type star
Gillon, Michaël ULg; Doyle, A. P.; Lendl, M. et al

in Astronomy and Astrophysics (2011), 533

We report the discovery by the WASP transit survey of a giant planet in a close orbit (0.0295 ± 0.0009 AU) around a moderately bright (V = 11.6, K = 10) G9 dwarf (0.89 ± 0.08 M[SUB]&sun;[/SUB], 0.84 ± 0 ... [more ▼]

We report the discovery by the WASP transit survey of a giant planet in a close orbit (0.0295 ± 0.0009 AU) around a moderately bright (V = 11.6, K = 10) G9 dwarf (0.89 ± 0.08 M[SUB]&sun;[/SUB], 0.84 ± 0.03 R[SUB]&sun;[/SUB]) in the Southern constellation Eridanus. Thanks to high-precision follow-up photometry and spectroscopy obtained by the telescopes TRAPPIST and Euler, the mass and size of this planet, WASP-50 b, are well constrained to 1.47 ± 0.09 M[SUB]Jup[/SUB] and 1.15 ± 0.05 R[SUB]Jup[/SUB], respectively. The transit ephemeris is 2 455 558.6120 (±0.0002) + N × 1.955096 (±0.000005) HJD[SUB]UTC[/SUB]. The size of the planet is consistent with basic models of irradiated giant planets. The chromospheric activity (log R'[SUB]HK = -4.67[/SUB]) and rotational period (P[SUB]rot[/SUB] = 16.3 ± 0.5 days) of the host star suggest an age of 0.8 ± 0.4 Gy that is discrepant with a stellar-evolution estimate based on the measured stellar parameters (ρ[SUB]∗[/SUB] = 1.48 ± 0.10 ρ[SUB]&sun;[/SUB], T[SUB]eff[/SUB] = 5400 ± 100 K, [Fe/H] = -0.12 ± 0.08) which favors an age of 7 ± 3.5 Gy. This discrepancy could be explained by the tidal and magnetic influence of the planet on the star, in good agreement with the observations that stars hosting hot Jupiters tend to show faster rotation and magnetic activity. We measure a stellar inclination of 84[SUB]-31[SUP]+6[/SUP][/SUB] deg, disfavoring a high stellar obliquity. Thanks to its large irradiation and the relatively small size of its host star, WASP-50 b is a good target for occultation spectrophotometry, making it able to constrain the relationship between hot Jupiters' atmospheric thermal profiles and the chromospheric activity of their host stars. The photometric time-series used in this work are only available at the CDS via anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or via <A href="http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/533/A88">http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/533/A88</A> [less ▲]

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See detailWASP-40b: Independent Discovery of the 0.6 M Transiting Exoplanet HAT-P-27b
Anderson, D. R.; Barros, S. C. C.; Boisse, I. et al

in Publications of the Astronomical Society of the Pacific [=PASP] (2011), 123

From WASP photometry and SOPHIE radial velocities we report the discovery of WASP-40b (HAT-P-27b), a 0.6 M planet that transits its 12th magnitude host star every 3.04 days. The host star is of late G ... [more ▼]

From WASP photometry and SOPHIE radial velocities we report the discovery of WASP-40b (HAT-P-27b), a 0.6 M planet that transits its 12th magnitude host star every 3.04 days. The host star is of late G-type or early K-type and likely has a metallicity greater than solar ([Fe/H]=0.14±0.11). The planet's mass and radius are typical of the known hot Jupiters, thus adding another system to the apparent pileup of transiting planets with periods near 3-4 days. Our parameters match those of the recent HATnet announcement of the same planet, thus giving confidence in the techniques used. We report a possible indication of stellar activity in the host star. [less ▲]

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See detailWASP-34b: a near-grazing transiting sub-Jupiter-mass exoplanet in a hierarchical triple system
Smalley, B.; Anderson, D. R.; Collier Cameron, A. et al

in Astronomy and Astrophysics (2011), 526

We report the discovery of WASP-34b, a sub-Jupiter-mass exoplanet transiting its 10.4-magnitude solar-type host star (1SWASP J110135.89-235138.4; TYC 6636-540-1) every 4.3177 days in a slightly eccentric ... [more ▼]

We report the discovery of WASP-34b, a sub-Jupiter-mass exoplanet transiting its 10.4-magnitude solar-type host star (1SWASP J110135.89-235138.4; TYC 6636-540-1) every 4.3177 days in a slightly eccentric orbit (e = 0.038 +/- 0.012). We find a planetary mass of 0.59 +/- 0.01 M_Jup and radius of 1.22 ^{+0.11}_{-0.08} R_Jup. There is a linear trend in the radial velocities of 55+/-4 m/s/y indicating the presence of a long-period third body in the system with a mass > 0.45 M_Jup at a distance of >1.2 AU from the host star. This third-body is either a low-mass star, white dwarf, or another planet. The transit depth ((R_P/R_*)^2 = 0.0126) and high impact parameter (b = 0.90) suggest that this could be the first known transiting exoplanet expected to undergo grazing transits, but with a confidence of only ~80%. [less ▲]

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See detailWASP-25b: a 0.6 M-J planet in the Southern hemisphere
Enoch, B.; Cameron, A Collier; Anderson, D. R. et al

in Monthly Notices of the Royal Astronomical Society (2011), 410(3), 16311636

We report the detection of a 0.6 M-J extrasolar planet by WASP-South, WASP-25b, transiting its solar-type host star every 3.76d. A simultaneous analysis of the WASP, FTS and Euler photometry and CORALIE ... [more ▼]

We report the detection of a 0.6 M-J extrasolar planet by WASP-South, WASP-25b, transiting its solar-type host star every 3.76d. A simultaneous analysis of the WASP, FTS and Euler photometry and CORALIE spectroscopy yields a planet of R[SUB]p[/SUB] = 1.22 R[SUB]J[/SUB] and M[SUB]p[/SUB] = 0.58 M[SUB]J[/SUB] around a slightly metal-poor solar-type host star, [Fe/H] = - 0.05 +/- 0.10, of R[SUB]*[/SUB] = 0.92 R[SUB]solar[/SUB] and M[SUB]*[/SUB] = 1.00 M[SUB]solar[/SUB]. WASP-25b is found to have a density of ρ[SUB]p[/SUB] = 0.32 ρ[SUB]J[/SUB], a low value for a sub-Jupiter mass planet. We investigate the relationship of planetary radius to planetary equilibrium temperature and host star metallicity for transiting exoplanets with a similar mass to WASP-25b, finding that these two parameters explain the radii of most low-mass planets well. [less ▲]

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See detailWASP-30b: a 61 Mjup brown dwarf transiting a V=12, F8 star
Anderson, D. R.; Collier Cameron, A.; Hellier, C. et al

in Astrophysical Journal Letters (2011), 726(2), 19

We report the discovery of a 61-Jupiter-mass brown dwarf (BD), which transits its F8V host star, WASP-30, every 4.16 days. From a range of age indicators we estimate the system age to be 1-2 Gyr. We ... [more ▼]

We report the discovery of a 61-Jupiter-mass brown dwarf (BD), which transits its F8V host star, WASP-30, every 4.16 days. From a range of age indicators we estimate the system age to be 1-2 Gyr. We derive a radius (0.89 ± 0.02 R Jup) for the companion that is consistent with that predicted (0.914 R Jup) by a model of a 1 Gyr old, non-irradiated BD with a dusty atmosphere. The location of WASP-30b in the minimum of the mass-radius relation is consistent with the quantitative prediction of Chabrier & Baraffe, thus confirming the theory. [less ▲]

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See detailWASP-22 b: A Transiting "Hot Jupiter" Planet in a Hierarchical Triple System
Maxted, P. F. L.; Anderson, D. R.; Gillon, Michaël ULg et al

in Astrophysical Journal (2010), 140(6), 2007-2012

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[/SUB] = 6000 ± 100 K, [Fe/H] = –0.05 ± 0.08 ... [more ▼]

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[/SUB] = 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[/SUB] = 0.56 ± 0.02M [SUB]Jup[/SUB] and a radius R [SUB]p[/SUB] = 1.12 ± 0.04R [SUB]Jup[/SUB]. In addition, there is a linear trend of 40 m s[SUP]–1[/SUP] yr[SUP]–1[/SUP] 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. [less ▲]

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See detailWASP-29b: A Saturn-sized Transiting Exoplanet
Hellier, Coel; Anderson, D. R.; Collier Cameron, A. et al

in Astrophysical Journal Letters (2010), 723

We report the discovery of a Saturn-sized planet transiting a V = 11.3, K4 dwarf star every 3.9 days. WASP-29b has a mass of 0.24 ± 0.02 M [SUB]Jup[/SUB] and a radius of 0.79 ± 0.05 R [SUB]Jup[/SUB ... [more ▼]

We report the discovery of a Saturn-sized planet transiting a V = 11.3, K4 dwarf star every 3.9 days. WASP-29b has a mass of 0.24 ± 0.02 M [SUB]Jup[/SUB] and a radius of 0.79 ± 0.05 R [SUB]Jup[/SUB], making it the smallest planet so far discovered by the WASP survey, and the exoplanet most similar in mass and radius to Saturn. The host star WASP-29 has an above-solar metallicity and fits a possible correlation for Saturn-mass planets such that planets with higher-metallicity host stars have higher core masses and thus smaller radii. [less ▲]

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See detailWASP-24 b: A New Transiting Close-in Hot Jupiter Orbiting a Late F-star
Street, R. A.; Simpson, E.; Barros, S. C. C. et al

in Astrophysical Journal (2010), 720

We report the discovery of a new transiting close-in giant planet, WASP-24 b, in a 2.341 day orbit, 0.037 AU from its F8-9 type host star. By matching the star's spectrum with theoretical models, we infer ... [more ▼]

We report the discovery of a new transiting close-in giant planet, WASP-24 b, in a 2.341 day orbit, 0.037 AU from its F8-9 type host star. By matching the star's spectrum with theoretical models, we infer an effective temperature T [SUB]eff[/SUB] = 6075 ± 100 K and a surface gravity of log g = 4.15 ± 0.10. A comparison of these parameters with theoretical isochrones and evolutionary mass tracks places only weak constraints on the age of the host star, which we estimate to be 3.8[SUP]+1.3[/SUP] [SUB]-1.2[/SUB] Gyr. The planetary nature of the companion was confirmed by radial velocity measurements and additional photometric observations. These data were fit simultaneously in order to determine the most probable parameter set for the system, from which we infer a planetary mass of 1.071[SUP]+0.036[/SUP] [SUB]-0.038[/SUB] M [SUB]Jup[/SUB] and radius 1.3[SUP]+0.039[/SUP] [SUB]-0.037[/SUB] R [SUB]Jup[/SUB]. [less ▲]

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See detailWASP-26b: A 1-Jupiter-mass planet around an early-G-type star
Smalley, B.; Anderson, D. R.; Collier Cameron, A. et al

in Astronomy and Astrophysics (2010)

We report the discovery of WASP-26b, a moderately over-sized Jupiter-mass exoplanet transiting its 11.3-magnitude early-G-type host star (1SWASP J001824.70-151602.3; TYC 5839-876-1) every 2.7566 days. A ... [more ▼]

We report the discovery of WASP-26b, a moderately over-sized Jupiter-mass exoplanet transiting its 11.3-magnitude early-G-type host star (1SWASP J001824.70-151602.3; TYC 5839-876-1) every 2.7566 days. A simultaneous fit to transit photometry and radial-velocity measurements yields a planetary mass of 1.02 +/- 0.03 M_Jup and radius of 1.32 +/- 0.08 R_Jup. The host star, WASP-26, has a mass of 1.12 +/- 0.03 M_sun and a radius of 1.34 +/- 0.06 R_sun and is in a visual double with a fainter K-type star. The two stars are at least a common-proper motion pair with a common distance of around 250 +/- 15 pc and an age of 6 +/- 2 Gy. [less ▲]

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See detailWASP-17b: an ultra-low density planet in a probable retrograde orbit
Anderson, D. R.; Hellier, C.; Gillon, Michaël ULg et al

in Astrophysical Journal (2010), 709(1), 159-167

We report the discovery of the transiting giant planet WASP-17b, the least-dense planet currently known. It is 1.6 Saturn masses but 1.5-2 Jupiter radii, giving a density of 6-14 per cent that of Jupiter ... [more ▼]

We report the discovery of the transiting giant planet WASP-17b, the least-dense planet currently known. It is 1.6 Saturn masses but 1.5-2 Jupiter radii, giving a density of 6-14 per cent that of Jupiter. WASP-17b is in a 3.7-day orbit around a sub-solar metallicity, V = 11.6, F6 star. Preliminary detection of the Rossiter-McLaughlin effect suggests that WASP-17b is in a retrograde orbit (lambda ~ -150 deg), indicative of a violent history involving planet-planet or planet-star scattering. WASP-17b's bloated radius could be due to tidal heating resulting from recent or ongoing tidal circularisation of an eccentric orbit, such as the highly eccentric orbits that typically result from scattering interactions. It will thus be important to determine more precisely the current orbital eccentricity by further high-precision radial velocity measurements or by timing the secondary eclipse, both to reduce the uncertainty on the planet's radius and to test tidal-heating models. Owing to its low surface gravity, WASP-17b's atmosphere has the largest scale height of any known planet, making it a good target for transmission spectroscopy. [less ▲]

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See detailWASP-19b: The Shortest Period Transiting Exoplanet Yet Discovered
Hebb, L.; Collier-Cameron, A.; Triaud, A H M J et al

in Astrophysical Journal (2010), 708

We report on the discovery of a new extremely short period transiting extrasolar planet, WASP-19b. The planet has mass M [SUB]pl[/SUB] = 1.15 ± 0.08 M[SUB]J[/SUB] , radius R [SUB]pl[/SUB] = 1.31 ± 0.06 ... [more ▼]

We report on the discovery of a new extremely short period transiting extrasolar planet, WASP-19b. The planet has mass M [SUB]pl[/SUB] = 1.15 ± 0.08 M[SUB]J[/SUB] , radius R [SUB]pl[/SUB] = 1.31 ± 0.06 R[SUB]J[/SUB] , and orbital period P = 0.7888399 ± 0.0000008 days. Through spectroscopic analysis, we determine the host star to be a slightly super-solar metallicity ([M/H] = 0.1 ± 0.1 dex) G-dwarf with T [SUB]eff[/SUB] = 5500 ± 100 K. In addition, we detect periodic, sinusoidal flux variations in the light curve which are used to derive a rotation period for the star of P [SUB]rot[/SUB] = 10.5 ± 0.2 days. The relatively short stellar rotation period suggests that either WASP-19 is somewhat young (~ 600 Myr old) or tidal interactions between the two bodies have caused the planet to spiral inward over its lifetime resulting in the spin-up of the star. Due to the detection of the rotation period, this system has the potential to place strong constraints on the stellar tidal quality factor, Q'[SUB] s [/SUB], if a more precise age is determined. [less ▲]

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See detailAn orbital period of 0.94days for the hot-Jupiter planet WASP-18b
Hellier, Coel; Anderson, D. R.; Cameron, A Collier et al

in Nature (2009), 460

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 ... [more ▼]

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 ~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 0.94days and a mass of ten Jupiter masses (10M[SUB]Jup[/SUB]), 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[SUP]6[/SUP], 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. [less ▲]

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See detailDiscovery and characterization of WASP-6b, an inflated sub-Jupiter mass planet transiting a solar-type star
Gillon, Michaël ULg; Anderson, D. R.; Triaud, A H M J et al

in Astronomy and Astrophysics (2009), 501

We report the discovery of WASP-6b, an inflated sub-Jupiter mass planet transiting every 3.3610060[SUP]+ 0.0000022 [/SUP][SUB]- 0.0000035 [/SUB] days a mildly metal-poor solar-type star of magnitude V ... [more ▼]

We report the discovery of WASP-6b, an inflated sub-Jupiter mass planet transiting every 3.3610060[SUP]+ 0.0000022 [/SUP][SUB]- 0.0000035 [/SUB] days a mildly metal-poor solar-type star of magnitude V = 11.9. A combined analysis of the WASP photometry, high-precision followup transit photometry and radial velocities yield a planetary mass M[SUB]p[/SUB] = 0.503[SUP]+0.019[/SUP][SUB]-0.038[/SUB] M[SUB]J[/SUB] and radius R[SUB]p[/SUB] = 1.224[SUP]+0.051[/SUP][SUB]-0.052[/SUB] R_J, resulting in a density rho[SUB]p[/SUB] = 0.27 ± 0.05 rho_J. The mass and radius for the host star are M_ast = 0.88[SUP]+0.05[/SUP][SUB]-0.08[/SUB] M_o and R_ast = 0.870[SUP]+0.025[/SUP][SUB]-0.036[/SUB] R_o. The non-zero orbital eccentricity e = 0.054^+0.018[SUB]-0.015[/SUB] that we measure suggests that the planet underwent a massive tidal heating 1 Gyr ago that could have contributed to its inflated radius. High-precision radial velocities obtained during a transit allow us to measure a sky-projected angle between the stellar spin and orbital axis beta = 11[SUP]+14[/SUP][SUB]-18[/SUB] deg. In addition to similar published measurements, this result favors a dominant migration mechanism based on tidal interactions with a protoplanetary disk. Based on data collected with the HARPS spectrograph at ESO La Silla Observatory in the programs 082.C-0040(E) and 082.C-0608. The photometric time-series and radial velocities (Tables 4, 5) used in this work are only available in electronic form at the CDS via anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or via http://cdsweb.u-strasbg.fr/cgi-bin/qcat?J/A+A/501/785 [less ▲]

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See detailThe Low Density Transiting Exoplanet WASP-15b
West, R. G.; Anderson, D. R.; Gillon, Michaël ULg et al

in Astronomical Journal (The) (2009), 137

We report the discovery of a low-density exoplanet transiting an 11th magnitude star in the Southern hemisphere. WASP-15b, which orbits its host star with a period P = 3.7520656 ± 0.0000028 d, has a mass ... [more ▼]

We report the discovery of a low-density exoplanet transiting an 11th magnitude star in the Southern hemisphere. WASP-15b, which orbits its host star with a period P = 3.7520656 ± 0.0000028 d, has a mass M [SUB]p[/SUB] = 0.542 ± 0.050 M [SUB]J[/SUB] and radius R [SUB]p[/SUB] = 1.428 ± 0.077 R [SUB]J[/SUB], and is therefore one of the least dense transiting exoplanets so far discovered (rho[SUB]p[/SUB] = 0.247 ± 0.035 g cm[SUP]--3[/SUP]). An analysis of the spectrum of the host star shows it to be of spectral type around F5, with an effective temperature T [SUB]eff[/SUB] = 6300 ± 100 K and [Fe/H] = --0.17 ± 0.11. [less ▲]

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See detailWASP-5b: a dense, very hot Jupiter transiting a 12th-mag Southern-hemisphere star
Anderson, D. R.; Gillon, Michaël ULg; Hellier, C. et al

in Monthly Notices of the Royal Astronomical Society (2008), 387

We report the discovery of WASP-5b, a Jupiter-mass planet orbiting a 12th-mag G-type star in the Southern hemisphere. The 1.6-d orbital period places WASP-5b in the class of very hot Jupiters and leads to ... [more ▼]

We report the discovery of WASP-5b, a Jupiter-mass planet orbiting a 12th-mag G-type star in the Southern hemisphere. The 1.6-d orbital period places WASP-5b in the class of very hot Jupiters and leads to a predicted equilibrium temperature of 1750K. WASP-5b is the densest of any known Jovian-mass planet, being a factor of 7 denser than TrES-4, which is subject to similar stellar insolation, and a factor of 3 denser than WASP-4b, which has a similar orbital period. We present transit photometry and radial velocity measurements of WASP-5 (= USNO-B10487-0799749), from which we derive the mass, radius and density of the planet: M[SUB]P[/SUB] = 1.58[SUP]+0.13[/SUP][SUB]-0.08[/SUB]M[SUB]J[/SUB],R[SUB]P[/SUB] = 1.090[SUP]+0.094[/SUP][SUB]-0.058[/SUB]R[SUB]J[/SUB] and rho[SUB]P[/SUB] = 1.22[SUP]+0.19[/SUP][SUB]-0.24[/SUB]rho[SUB]J[/SUB]. The orbital period is P = 1.6284296[SUP]+0.0000048[/SUP][SUB]-0.0000037[/SUB]d and the mid-transit epoch is T[SUB]C[/SUB](HJD) = 2454375.62466[SUP]+0.00026[/SUP][SUB]-0.00025[/SUB]. [less ▲]

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See detailWASP-4b: A 12th Magnitude Transiting Hot Jupiter in the Southern Hemisphere
Wilson, D. M.; Gillon, Michaël ULg; Hellier, C. et al

in Astrophysical Journal (2008), 675

We report the discovery of WASP-4b, a large transiting gas-giant planet with an orbital period of 1.34 days. This is the first planet to be discovered by the SuperWASP-South observatory and CORALIE ... [more ▼]

We report the discovery of WASP-4b, a large transiting gas-giant planet with an orbital period of 1.34 days. This is the first planet to be discovered by the SuperWASP-South observatory and CORALIE collaboration and the first planet orbiting a star brighter than 16th magnitude to be discovered in the southern hemisphere. A simultaneous fit to high-quality light curves and precision radial velocity measurements leads to a planetary mass of 1.22[SUP]+0.09[/SUP][SUB]-0.08[/SUB] M[SUB]Jup[/SUB] and a planetary radius of 1.42[SUP]+0.07[/SUP][SUB]-0.04[/SUB] R[SUB]Jup[/SUB]. The host star is USNO-B1.0 0479-0948995, a G7 V star of visual magnitude 12.5. As a result of the short orbital period, the predicted surface temperature of the planet is 1761 K, making it an ideal candidate for detections of the secondary eclipse at infrared wavelengths. [less ▲]

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