SuperWASP Results

Although 70 transiting planets is a truly respectable number, it is nowhere near to the thousands of planets they expected to see in the beginning. See for example this PR release.

Hot Jupiters are not common, and it's terribly tricky to weed out the false positives.

I remember seeing a figure of a total of only 200 planets the project (with HatNET) should be able to detect. That would mean half of the detectable planets have been already found. Has somebody have seen this figure, or am I imagining things?

Some updates for WASP-10 b

Analysis of new high-precision transit light curves of WASP-10 b: starspot occultations, small planetary radius, and high metallicity

Quote :

The WASP-10 planetary system is intriguing because different values of radius have been reported for its transiting exoplanet. The host star exhibits activity in terms of photometric variability, which is caused by the rotational modulation of the spots. Moreover, a periodic modulation has been discovered in transit timing of WASP-10 b, which could be a sign of an additional body perturbing the orbital motion of the transiting planet. We attempt to refine the physical parameters of the system, in particular the planetary radius, which is crucial for studying the internal structure of the transiting planet. We also determine new mid-transit times to confirm or refute observed anomalies in transit timing. We acquired high-precision light curves for four transits of WASP-10 b in 2010. Assuming various limb-darkening laws, we generated best-fit models and redetermined parameters of the system. The prayer-bead method and Monte Carlo simulations were used to derive error estimates. Three transit light curves exhibit signatures of the occultations of dark spots by the planet during its passage across the stellar disk. The influence of stellar activity on transit depth is taken into account while determining system parameters. The radius of WASP-10 b is found to be no greater than 1.03 Jupiter radii, a value significantly smaller than most previous studies indicate. We calculate interior structure models of the planet, assuming a two-layer structure with one homogeneous envelope atop a rock core. The high value of the WASP-10 b's mean density allows one to consider the planet's internal structure including 270 to 450 Earth masses of heavy elements. Our new mid-transit times confirm that transit timing cannot be explained by a constant period if all literature data points are considered. They are consistent with the ephemeris assuming a periodic variation of transit timing.

The radius of the planet 1.03 is the greatest possible because there can be still some star spots left not included in calculation

WASP-36b: A new transiting planet around a metal-poor G-dwarf, and an analysis of correlated noise in transit light curves

http://arxiv.org/abs/1110.5313

Quote :

We report the discovery, from WASP and CORALIE, of a transiting exoplanet in a 1.54-d orbit. The host star, WASP-36, is a magnitude 12.7, metal-poor G2 dwarf (Teff = 5881 +/- 137 K), with [Fe/H] = -0.31 +/- 0.12. We determine the planet to have mass and radius respectively 2.27 +/- 0.07 and 1.27 +/- 0.03 times that of Jupiter. We have eight partial or complete transit light curves, from four different observatories, which allows us to investigate the extent to which red noise in follow-up light curves affects the fitted system parameters. We find that the solutions obtained by analysing each of these light curves independently are consistent with our global fit to all the data, despite the apparent presence of correlated noise in at least two of the light curves.

At last!! It was one year and more after early release with a simple poster!

I see the radius significantly scaled down from 1.4 to 1.27 Jupiter radii. Still a partly inflated hot Jupiter btw

Another counterexample to the idea that all very highly irradiated planets have thermal inversions, and cooler ones don't: WASP-14 b.
http://arxiv.org/abs/1111.2363

Sirius_Alpha wrote:

Measurements of Transit Timing Variations for WASP-5b
http://arxiv.org/abs/1009.5769

Guess not.

Transit Monitoring in the South (TraMoS) project: Discarding Transit Timing Variations in WASP-5b
http://arxiv.org/abs/1201.3616

Quote :

We report nine new transit epochs of the extrasolar planet, observed in the Bessell-I band with SOAR at the Cerro Pachon Observatory and with the SMARTS 1-m Telescope at CTIO, between August 2008 and October 2009. The new transits have been combined with all previously published transit data for this planet to provide a new Transit Timing Variations (TTVs) analysis of its orbit. We find no evidence of TTVs RMS variations larger than 1 min over a 3 year time span. This result discards the presence of planets more massive than about 5 M_earth, 1 M_earth and 2 M_earth around the 1:2, 5:3 and 2:1 orbital resonances. These new detection limits exceed by ~5-30 times the limits imposed by current radial velocity observations in the Mean Motion Resonances of this system. Our search for the variation of other parameters, such as orbital inclination and transit depth also yields negative results over the total time span of the transit observations. This result supports formation theories that predict a paucity of planetary companions to Hot Jupiters.

Another study of several transits of a WASP planet:

The TRAPPIST survey of southern transiting planets. I. Thirty eclipses of the ultra-short period planet WASP-43 b

Spin-orbit alignment constraints for WASP-16, WASP-25 and WASP-31
http://arxiv.org/abs/1203.4971

Seven transiting hot-Jupiters from WASP-South, Euler and TRAPPIST: WASP-47b, WASP-55b, WASP-61b, WASP-62b, WASP-63b, WASP-66b & WASP-67b
http://arxiv.org/abs/1204.5095

The same paper also hints about additional - yet unpublished - WASP planets up to WASP-84 b.

Check: http://www.astro.keele.ac.uk/~ch/wasps.html

So far SuperWASP Survey is the one so far having the highest number of confirmed transiting planets. More than CoRoT and Kepler as well.

WASP-42 b and WASP-49 b: two new transiting Saturns

A couple of hot, sub-Jupiter-mass planets.

Probing the extreme planetary atmosphere of WASP-12b
http://arxiv.org/abs/1205.4736

Comprehensive time series analysis of the transiting extrasolar planet WASP-33b

There appears to be a belt of starspots causing a brightening during the transit, which is odd for a metallic line star (spectral type kA5hA8mF4). Radial velocity measurements have also been used to get a value for the mass (as opposed to the upper limit previously obtained) of 3.18±0.82 Jupiter masses.

Secondary Eclipse measurements: Poor heat redistribution in WASP-33 b, orbit is likely circular.
http://arxiv.org/abs/1206.0774

Wow, very large giant planets!

WASP-78b and WASP-79b: Two highly-bloated hot Jupiter-mass exoplanets orbiting F-type stars in Eridanus
http://arxiv.org/abs/1206.1177

Quote :

We report the discovery of WASP-78b and WASP-79b, two highly-bloated Jupiter-mass exoplanets orbiting F-type host stars. WASP-78b orbits its V=12.0 host star (TYC 5889-271-1) every 2.175 days and WASP-79b orbits its V=10.1 host star (CD-30 1812) every 3.662 days. A simultaneous fit to WASP and TRAPPIST transit photometry and CORALIE radial-velocity measurements yields planetary masses of 0.89 +/- 0.08 M_Jup and 0.90 +/- 0.08 M_Jup, and radii of 1.70 +/- 0.11 R_Jup and 2.09 +/- 0.14 R_Jup, for WASP-78b and WASP-79b, respectively. The planetary equilibrium temperature of T_P = 2350 +/- 80 K for WASP-78b makes it one of the hottest of the currently known exoplanets. The radius of WASP-79b suggests that it is potentially the largest known exoplanet.

So many different values of planets radius in this paper .

For each planet, two solutions are given. One assumes the star is a Main-Sequence star, the other assumes it's heading off the Main Sequence. It's important to take this into account because it affects assumptions about the stellar radius, and in turn, the planetary radius. Apparently for both stars, it's not exactly clear if it's moving off the main sequence, so they're taking the side of caution and presenting both solutions.

arXiv:1206.3585v1 [astro-ph.EP]: z'-band Ground-Based Detection of the Secondary Eclipse of WASP-19b

Yes, WASP-17b is a large planet.

High-precision photometry by telescope defocussing. IV. Confirmation of the huge radius of WASP-17b

WASP-54b, WASP-56b and WASP-57b: Three new sub-Jupiter mass planets from SuperWASP
http://arxiv.org/abs/1210.2329

The hot sub-Jupiters don't seem to be playing ball with the ohmic heating hypothesis for inflating planetary radii.

Seems we still don't know very much about the fundamentals of hot Jupiter physics...

TASTE. III. A homogeneous study of transit time variations in WASP-3b
http://arxiv.org/abs/1210.3045

Unable to confirm the previously reported TTV's for WASP-3, but the TTVs are not consistent with a constant period.

WASP-64b and WASP-72b
http://arxiv.org/abs/1210.4257

Re-Evaluating WASP-12b: Strong Emission at 2.315 micron, Deeper Occultations, and an Isothermal Atmosphere
http://arxiv.org/abs/1210.4836

There is another star that was contaminating the light. Bergfors-6 may be a foreground red dwarf, but the RV is similar to WASP-12 so it could be associated with the system if it is actually an unresolved binary.

High C/O ratio appears to be excluded.

Quote :

Regardless, our narrowband measurement alone excludes the models used to infer this high C/O ratio at > 3σ. The lack of absorption at a wavelength where CO, a dominant species in any atmospheric model, should exhibit strong absorption is further evidence for a near-isothermal photosphere. Thus secondary eclipse observations are ill-suited to determine WASP-12b’s atmospheric composition, and ultimately transmission spectroscopy may be a more successful approach in pursuit of this goal.