In traditional transit timing variations (TTVs) analysis of multi-planetary systems, the individual TTVs are first derived from transit fitting and later modelled using n-body dynamic simulations to constrain planetary masses. We show that fitting simultaneously the transit light curves with the system dynamics (photo-dynamical model) increases the precision of the TTV measurements and helps constrain the system architecture. We exemplify the advantages of applying this photo-dynamical model to a multi-planetary system found in K2 data very close to 3:2 mean motion resonance, K2-19. In this case the period of the larger TTV variations (libration period) is much longer (>1.5 years) than the duration of the K2 observations (80 days). However, our method allows to detect the short period TTVs produced by the orbital conjunctions between the planets that in turn permits to uniquely characterise the system. Therefore, our method can be used to constrain the masses of near-resonant systems even when the full libration curve is not observed.

We observed with HARPS, the Rossiter-McLaughlin effect for 40 of the 75 transiting hot Jupiters discovered in the Southern Hemisphere by WASP. Our observations reveal a wide distribution in orbital inclinations indicative of past dynamical interactions. Our data also demonstrate the important effect produced by tidal interactions in shaping the spin–orbit (β) angle distribution. We briefly present and interpret the data we collected in a series of graphs.

We present radial-velocity measurements (RV) obtained in one of the numbers of programs underway to search for extrasolar planets with the spectrograph SOPHIE at the 1.93-m telescope of the Observatoire de Haute-Provence. Targets were selected from catalogs observed with ELODIE, which had been mounted previously at the telescope, in order to detect long-period planets with an extended database close to 15 years.

Charge Transfer Inefficiency (CTI) is a well known effect of charge-coupled devices (CCD). The charge transfer from one pixel to the next is not perfect and is quantified by the fraction of charge successfully moved (clocked) between adjacent pixels. The amplitude of this effect depends on the signal level inside the pixel. In the context of high-precision radial velocity measurements using cross-dispersed echelle spectrograph, this CTI effect on a CCD recording spectral orders may introduce associated spectral lines shifts. Indeed if the signal level recorded on the spectra is changing, the CTI amplitude will change affecting the associated centroid of all spectral lines. Such effect may introduced radial velocity shifts of several  m s-1. We describe here CTI effect which is affecting the SOPHIE spectrograph installed on the 1.93-m telescope of Observatoire de Haute Provence (OHP). We calibrated the effect thanks to the Thorium-Argon lines and we applied a software correction on the spectra in order to assess the charge lost during the readout process on all pixels.

The SOPHIE Consortium started a large program of exoplanets search and characterization in the Northern hemisphere with the new spectrograph SOPHIE at the 1.93-m telescope of Haute-Provence Observatory, France. The objectives of this program are to characterize the zoo of exoplanets and to bring strong constraints on their processes of formation and evolution using the radial velocity technique. We present here new SOPHIE measurements of the transiting planet host star XO-3. This allowed us to observe the Rossiter-McLaughlin effect and to refine the parameters of the planet. The unusual shape of the radial velocity anomaly during the transit provides a hint for a nearly transverse Rossiter-McLaughlin effect. The sky-projected angle between the planetary orbital axis and the stellar rotation axis should be λ = 70° ± 15° to be compatible with our observations. This suggests that some close-in planets might result from gravitational interaction between planets and/or stars rather than migration. This result requires confirmation by additional observations.

The HARPS search for low-mass extrasolar planets has been ongoing for more than 4 years, targeting originally about 400 bright FGK dwarfs in the solar neighbourhood. The published low-mass planetary systems coming from this survey are fully confirmed by subsequent observations, which demonstrate the sub-m/s long-term stability reached by HARPS. The complex RV curves of these systems have led us to focus on a smaller sample of stars, accumulating more data points per star. We perform a global search in our data to assess the existence of the large population of ice giants and super-Earths predicted by numerical simulations of planet formation. We indeed detect about 45 candidates having minimum masses below 30 M⊕ and orbital periods below 50 days. These numbers are preliminary since the existence of these objects has to be confirmed by subsequent observations. However, they indicate that about 30% of solar-type stars may have such close-in, low-mass planets. Some emerging properties of this low-mass population are presented. We finally discuss the prospects for finding transiting objects among these candidates, which may possibly yield the first nearby, transiting super-Earth.

Exoplanet search programs need to study how to disentangle radial-velocity (RV) variations due to Doppler motion and the noise induced by stellar activity. We monitored the active K2V HD 189733 with the high-resolution SOPHIE spectrograph (OHP, France). We refined the orbital parameters of HD 189733b and put limitations on the eccentricity and on a long-term velocity gradient. We subtracted the orbital motion of the planet and compared the variability of activity spectroscopic indices (HeI, Hα, Ca II H&K lines) to the evolution of the RV residuals and the shape of spectral lines. All are in agreement with an active stellar surface in rotation. We used such correlations to correct for the RV jitter due to stellar activity. This results in achieving a high precision on the orbital parameters, with a semi-amplitude: K=200.56±0.88m⋅s−1 and a derived planet mass of MP=1.13±0.03 MJup.

We present “A STEP” (Antarctica Search for Transiting ExtrasolarPlanets), a project dedicated to the search for planetary transitsfrom Antartica. The project consists of a semi-automatic ~40 cmtelescope equipped with a 16-million-pixel CCD installed at DomeC. The site offers crucial assets for a ground-based exoplanet transitsearch: uninterrupted phase coverage, excellent weather, low air-massvariations and reduced scintillation.
This system would be able to detect Pegasids transiting in front ofstars as faint as magnitude sixteen and could also detect smallerplanets in close-in period around brighter stars. This short termproject is meant to be a photometric qualifyer for the site and thefirst stage of a massive detection campaign. A mid-term objective of1000 detections for 2012 could be achieved either with many smalltelescopes or with a large Schmidt telescope with a large field ofview.
The project is relatively simple and cost-effective, and has thedouble purpose of qualifying the site and obtaining first-classscientific results. Our team is already familiar with transitdetection with an automated telescope and cold temperaturequalification.


The combination of the collecting power of an ELT with an ultra-stable high resolution spectrograph opens up the possibility to measure for the first time directly the dynamical effect of the acceleration of the Universe. CODEX will also provide unique opportunities for advance in many other branches of astrophysics. The CODEX design is based on an array of several identical spectrographs. It is highly modular and can be easily adapted to a large range of sky apertures and telescope diameters. CODEX is designed to work as a seeing limited instrument. The requirements for the telescope are moderate and clearly identified.

We study the potential impact of a photometric search for transiting exoplanets from Dome C. In the past year, four new transiting exoplanets have been found by ground-based surveys, including three detected by our follow-up of OGLE transit candidates with FLAMES/UVES on the VLT. Based on the experience of this survey, we have built a simulation to predict the expected number of transiting exoplanet detections from photometric searches. We apply these simulations to a possible survey based at Concordia. We find that the Antarctica location solves the two main limitations of ground-based transit surveys: the diurnal-cycle time sampling, and the hour-timescale systematic photometric variations. The expected numbers of detections are much larger than for other ground-based surveys. They show the high potential of such projects at Dome C, even with a small telescope.

Recent results of asteroseismology have been achieved on a growing list of solar-type stars thanks to high precision echelle spectrographs.These results indicates that Doppler measurements are more efficient from the ground than photometry for p-modes detections. A high precision spectrograph dedicated for Doppler asteroseismology based in Dome C will play an important and fundamental step in asteroseismology. Such an instrument coupled to an only 1-m class telescope will be able to reach a very high level of sensibility for p-mode detection on several tens of solar-type stars. Capabilities and expected performances in asteroseismology of a replica of the SOPHIE spectrograph (1.93-m OHP) based in Dome C are presented. Such an instrument is furthermore fully compatible and adapted for polarimetry studies and detection and characterization of extra-solar planets.

We present here a new result of ground-based asteroseismology obtained with the spectrograph HARPS. The exoplanets host star μ Arae was observed during an 8 nights campaign in order to understand the origin of the overmetallicity of planet-hosting stars. Thanks to very high precision Doppler measurements, we identified more than 20 p-modes in this star and compared it with different models. These results demonstrate the potential of ground-based Doppler asteroseismology and should be considered to be implemented in Dome C in the future in order to benefit of long and uninterrupted observations.

We present “A STEP”, a project dedicated to the search for planetarytransits from Antartica. The project consists of a fully automatic 40 cm telescope equipped with an 11-million-pixel CCD installed atDome C. The site offers crucial assets for a ground-based exoplanettransit search: uninterrupted phase coverage and excellentseeing. 
This system would be able to detect hot Jupiters transiting in frontof stars as faint as magnitude sixteen and could also detect smallerplanets in close-in period around brighter stars. Our estimations,based on results of previous surveys are an average of 6 detectionsper 60 days survey. Compared to existing surveys, this excellent yieldis due to the nearly-continuous phase coverage and excellent seiing.This short term project is meant to be a photometric qualifyer for thesite and the first stage of a massive detection campaign. A mid-termobjective of 1000 detections for 2012 could be achieved either with manysmall telescopes or with a large Schmidt telescope with a large fieldof view. 
The project is relatively simple and cost-effective, and has thedouble purpose of qualifying the site and obtaining first-classscientific results. Our team is already familiar with transitdetection with an automated telescope (BEST) and cold temperaturequalification.

The method of stellar velocity variations measurement has recently shown its capability by discovering tens of extra-solar planets. Accuracies achieved today are in the range of 3 to 10 m/s. The spectrograph EMILIE coupled to the Absolute Astronomical Accelerometer (AAA) system and established at the 1.52 m telescope of the Observatoire de Haute Provence is an instrument which aims at reaching an accuracy better than 1 m/s, long term. Results on some typical stars are presented.

Observations of solar-like oscillation frequencies allow us to constrain the theory of structure and evolution of stars with an outer convective zone. Recent improvements in radial velocity measurements have led to p-mode detection on Procyon (Martic et al., 1999) and β Hydri (Bedding et al., 2001; Carrier et al., 2001a). Very recently, characterization of the p-modes of α Cen A has been made with the spectrograph CORALIE mounted on the 1.2-m Swiss telescope at the ESO La Silla Observatory (Bouchy & Carrier, 2001, Carrier et al., these proceedings). The power of the radial velocity technique promises the development of ground-based search for solar-like oscillations on a large sample of stars especially with the future spectrograph HARPS.

Velocity measurements of the G2 subgiant β Hyi with both UCLES and CORALIE show a clear excess of power centred at 1.0 mHz. In the UCLES data we find evidence for a short-lived, high-amplitude oscillation event. If confirmed as a feature of subgiants, such ‘starquakes’ would make it harder to measure accurate mode frequencies and perform asteroseismology.

The spectrograph CORALIE reaches the radial velocity precision needed for an asteroseismological program on bright solar-like stars. We present here two results obtained with this instrument on the stars Procyon and β Hydri. A third campaign, on α Cen A, is presented independently in these proceedings by Carrier et al.

We have made a clear detection of p-mode oscillations in the G2V star α Cen A with the CORALIE spectrograph. The power spectrum clearly shows several identifiable peaks between 1.8 and 2.9 mHz. A preliminary astrophysical interpretation of these p-modes is presented.

The spectrograph EMILIE (Bouchy et al., 1999; Bouchy, 1999; Bouchy et al., 2000) coupled to the Absolute Astronomical Accelerometer (AAA, Connes, 1985; Schmitt, 1997) and implemented at the 152-cm Coudé telescope of the Observatoire de Haute Provence is dedicated to high-precision Doppler measurements. The AAA method uses a sliding reference spectrum constrained to track the stellar lines and to use the spectrograph as a null-checking device. The goal of AAA is to eliminate the calibration of the spectrograph as well as the displacement of the spectra across the CCD pixels due to the earth motion (and suspected to introduce a systematic error in the RV measurement). Here we report seismological results obtained with AAA on the Sun and the bright stars Procyon and ζ Her A that are expected to present solar-like oscillations.

We have observed Procyon with the fiber-fed échelle spectrograph ELODIE coupled with a Fabry-Perot etalon at the 193-cm of the Observatoire de Haute Provence (France) over 5 nights during 1997 December – 1998 January. Here, we present the results of a search for solar-like oscillations on this star and the performance of this instrumentation for asteroseismology. The power spectra show an excess of signal between 0.42 mHz and 1.46 mHz, which could be due to stellar oscillations.