* Astronomy

Title: The transiting planet OGLE-TR-132b revisited with new spectroscopy and deconvolution photometry
Authors: M. Gillon (1, 2), F. Pont (1), C. Moutou (3), N. C. Santos (1, 4, 5), F. Bouchy (6), J. D. Hartman (7), M. Mayor (1), C. Melo (8), D. Queloz (1), S. Udry (1), P. Magain (2) ((1) Geneva Observatory, Switzerland, (2) IAGL, Liege University, Belgium, (3) LAM, France, (4) Lisbona Observatory, Portugal, (5) CGE, Portugal, (6) IAP, Pierre & Marie Curie University, France, (7) Harvard-Smithsonian Center for Astrophysics, USA, (8) ESO, Chile)
(Version v2)

OGLE-TR-132b transits a very metal-rich F dwarf about 2000 pc from the Sun, in the Galactic disc towards Carina. It orbits very close to its host star (a = 0.03 AU) and has an equilibrium temperature of nearly 2000 K. Using rapid-cadence transit photometry from the FORS2 camera on the VLT and SUSI2 on the NTT, and high-resolution spectroscopy with UVES on the VLT, we refine the shape of the transit light curve and the parameters of the system. In particular, we improve the planetary radius estimate, R=1.18 ± 0.07 R_J and provide very precise ephemeris, T_tr=2453142.59123 ± 0.0003 BJD and P=1.689868 ± 0.000003 days. The obtained planetary mass is 1.14 ± 0.12 M_J. Our results give a slightly smaller and lighter star, and bigger planet, than previous values. As the VLT/FORS2 light curve obtained in this analysis with the deconvolution photometry algorithm DECPHOT shows a transit depth in disagreement with the one obtained by a previous study using the same data, we analyse them with two other reduction methods (aperture and image subtraction). The light curves obtained with the three methods are in good agreement, though deconvolution-based photometry is significantly more precise. It appears from these results that the smaller transit depth obtained in the previous study was due to a normalisation problem inherent to the reduction procedure used.

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Title: The SARG Planet Search
Authors: S. Desidera, R. Gratton, M. Endl, A.F. Martinez Fiorenzano, M. Barbieri, R. Claudi, R. Cosentino, S. Scuderi, M. Bonavita

In this chapter of the book "Planets in binaries" we summarise our recent work on the statistical properties of planets in binaries and the differences with respect to planets orbiting single stars. We then present the radial velocity planet search on moderately wide binaries with similar components (twins) ongoing at TNG using the high resolution spectrograph SARG. We discuss the sample selection, the observing and analysis procedures, and the preliminary results of the radial velocity monitoring. We also discuss the second major science goal of the SARG survey, the search for abundance anomalies caused by the ingestion of planetary material by the central star, considering the two samples of twins and the planet hosts in binaries with similar components. Finally, we present some preliminary conclusions on the frequency of planets in binary systems.

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Title: SuperWASP-N Extra-solar Planet Candidates Between 18hr < RA < 21hr
Authors: R.A. Street, D.J. Christian, W.I. Clarkson, A. Collier Cameron, B. Enoch, S.R. Kane, T.A. Lister, R.G. West, D.M. Wilson, A. Evans, A. Fitzsimmons, C.A. Haswell, C. Hellier, S.T. Hodgkin, K. Horne, J. Irwin, F.P. Keenan, A.J. Norton, J. Osborne, D.L. Pollacco, R. Ryans, I. Skillen, P.J. Wheatley, J. Barnes

The SuperWASP-I instrument observed 6.7 million stars between 8-15 mag from La Palma during the 2004 May-September season. Our transit-hunting algorithm selected 11,626 objects from the 184,442 stars within the range RA 18hr-21hr. We describe our thorough selection procedure whereby catalogue information is exploited along with careful study of the SuperWASP data to filter out, as far as possible, transit mimics. We have identified 35 candidates which we recommend for follow-up observations.

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Title: SuperWASP-North Extrasolar Planet Candidates. Candidates from Fields 17hr < RA < 18hr
Authors: T. A. Lister, R. G. West, D. M. Wilson, A. Collier Cameron, W. I. Clarkson, R. A. Street, B. Enoch, N. R. Parley, D. J. Christian, S. R. Kane, A. Evans, A. Fitzsimmons, C. A. Haswell, C. Hellier, S. T. Hodgkin, Keith Horne, J. Irwin, F. P. Keenan, A. J. Norton, J. Osborne, D. L. Pollacco, R. Ryans, I. Skillen, P. J. Wheatley, J. R. Barnes

We have performed photometric observations of nearly 7 million stars with 8 < V < 15 with the SuperWASP-North instrument from La Palma between 2004 May-September. Fields in the RA range 17-18hr, yielding over 185,000 stars with sufficient quality data, have been searched for transits using a modified box least-squares (BLS) algorithm. We find a total of 58 initial transiting candidates which have high S/N in the BLS, show multiple transit-like dips and have passed visual inspection. Analysis of the blending and inferred planetary radii for these candidates leaves a total of 7 transiting planet candidates which pass all the tests plus 4 which pass the majority. We discuss the derived parameters for these candidates and their properties and comment on the implications for future transit searches.

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A planet orbiting a nearby star is a water world, according to new research from a team of European astronomers which is published in the journal Astronomy and Astrophysics.
The planet was first discovered in 2004, orbiting a red dwarf star called GJ436, which is some 30 light years from the Sun. Its mass is 22 times that of the Earth and it orbits its star every 2.6 days at a distance of 4 million km.

Une équipe dastronomes menée par un chercheur de lUniversité de Liège a mesuré le transit dune petite planète de la taille de Neptune en dehors de notre système solaire. La mesure de ce transit permet pour la première fois daccéder à la structure dune planète de petite taille, et a mis en évidence le fait quelle est composée principalement deau, comme Uranus et Neptune.
Read more (French)