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Extrasolar Planet Observational Studies: The Italian Contribution. Raffaele Gratton INAF – Osservatorio Astronomico di Padova. Exoplanets science. Extrasolar planets one of the major astronomical topic of the last decade
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Extrasolar Planet Observational Studies: The Italian Contribution Raffaele Gratton INAF – Osservatorio Astronomico di Padova Congresso SAIt, Teramo, 8-5-2008
Exoplanets science Extrasolar planets one of the major astronomical topic of the last decade Increasing interest in the coming years, when moving to planets with lower masses, down to Earth-mass planets Many surprises: planets and planetary systems very different from the Solar System Congresso SAIt, Teramo, 8-5-2008
V391Peg SPHERE Red Giants Open Clusters EPICS SARG RATS PLATO GAIA ΩTrans M. Perryman, 2001(from: http://www.obspm.fr/encycl/searches.html) Congresso SAIt, Teramo, 8-5-2008
SARG: Planets in binaries Long Term Project using SARG at TNG Main Goals: - May planets form in close binaries? - Understand planet-metallicity connection Sample: ~100 nearly equal mass visual binaries (projected separation 100-1000 AU) Monitored over 8 years (~120 observing nights) Typical precision RV: 5 m/s • Collaboration of people in: • INAF-OAPD • INAF-OACT • CGG • Un. Texas at Austin Recent Publications: Desidera et al. (2007) astro-ph 0705.3141 Desidera & Barbieri (2007) A&A 462,345 Martinez Fiorenzano et al. (2005) A&A 442,775 Congresso SAIt, Teramo, 8-5-2008
SARG: Planets in binaries May planets form in close binaries? There are less planets in close binaries Congresso SAIt, Teramo, 8-5-2008
The planet-metallicity connection: • Either planets form more easily in environments more rich in metals (more grains) • -Or alteration of primordial abundances due to infall of metal-rich material • Stringent upper limits from binaries composed of very similar late-F early-G stars (where the convective envelope is tiny) SARG: Planets in binaries Congresso SAIt, Teramo, 8-5-2008
Extreme RV performances with SARG SARG use for asteroseismology campaigns reveals extreme RV performances: nigthly averages over a week have dispersions of about 20 cm/s, sensitivity to 2 MEarth planets in short periods Congresso SAIt, Teramo, 8-5-2008
SARG: Determine the frequency of Hot Neptunes Intensive program: ~60 nights/yr for two years at TNG 26 nights allocated at TNG for AOT17 Congresso SAIt, Teramo, 8-5-2008
First results: requested accuracy (1-2 m/s) achieved Candidates from lower accuracy program at McDonald Observatory Congresso SAIt, Teramo, 8-5-2008
Planets around Red Giants -1 • Group leadered by Luca Pasquini (ESO) • Italian contribution: Leo Girardi (INAF-OAPD) & Katia Biazzo (OACT) • Importance: Search for planets around quite massive stars • Data gathered at ESO & TLS telescopes • Results: >10 planets discovered Congresso SAIt, Teramo, 8-5-2008
Planets around Red Giants - 2 • Massive planets around massive stars are common (>10% of the stars) M<1.1 Mo M>1.1 Mo Congresso SAIt, Teramo, 8-5-2008
Planets around Red Giants - 3 • No correlation between presence of planets and metallicity, at variance with results G-K main sequence stars Congresso SAIt, Teramo, 8-5-2008
Time Delays: the case of V391 Pegasi (pulsating B subdwarf) • Group leader: Silvotti (OA Capodimonte) • Importance: Search for planets around evolved stars • Main Result: Quite unexpected discovery of a planet which survived stellar evolution on the RGB • References: - Silvotti et al., 2007, Nature, 449, 189 Congresso SAIt, Teramo, 8-5-2008
Transits: Open clusters • PI Piotto (Univ. PD) • Un. PD+INAF-OAPD • Do planets form also in dense environments? • Small statistics Metal-rich open clusters • NGC6791: • 10 nights at CFHT+San Pedro Martir+Loiano • NGC6253: • 10 nights at WFI@La Silla+AAT Congresso SAIt, Teramo, 8-5-2008
Transits: Open clusters Highly accurate photometric curves (error of a few thousandths of mag for the upper MS) Congresso SAIt, Teramo, 8-5-2008
Transits: Open clusters NGC6791: • Null result • detailed simulations foresee the presence of 2-3 transiting planets. • The probability that the null detection is simply due to chance coincidence is estimated to be 3%-10%, depending on the metallicity assumed for the cluster • New observations scheduled in July • NGC6253: 1 candidate Congresso SAIt, Teramo, 8-5-2008
Transits: TReS and HATP survey • Italian participant: A. Sozzetti (OATO) Publications: • Observational Tests of Planet Formation Models (ArXiv0711:0409) • HAT-P-4b: A metal-rich low-density transiting hot Jupiter (ArXiv0710:0602) • TrES-4: A Transiting Hot Jupiter of Very Low Density (ArXiv0708:0834) • HAT-P-3b: A heavy-element rich planet transiting a K dwarf star (ArXiv0707:4267) • TrES-3: A Nearby, Massive, Transiting Hot Jupiter in a 31-Hour Orbit (ArXiv0705:2004) • HD147506b: A Super-Massive Planet in an Eccentric Orbit Transiting a Bright Star (ArXiv0705:0126) • Improving Stellar and Planetary Parameters of Transiting Planet Systems: The Case of TrES-2 (ArXiv0704:2938) • The Transit Light Curve Project. VI. Three Transits of the Exoplanet TrES-2 (ArXiv0704:2907) • TrES-2: The First Transiting Planet in the Kepler Field (astro-ph/0609:9335) • A Keck/HIRES Doppler Search for Planets Orbiting Metal-Poor Dwarfs. I. Testing Giant Planet Formation and Migration Scenarios (astro-ph/0605067) Congresso SAIt, Teramo, 8-5-2008
Spectroscopic determination of the atmospheric parameters and chemical abundance of the parent star Detailed LTE analysis of a set of Fe I and Fe II lines yields Teff=5850±50 K, log g=4.4±0.1, and [Fe/H]=−0.15±0.10. New method to derive mass and radius of the star: M⋆ = 0.980±0.062 Mo R⋆=1.000±0.034 Ro Age = 5.1±2.5 Gyr Mp=1.198±0.053 MJ Rp=1.220±0.044 RJ, TrES-2 is the most massive among the currently known nearby transiting hot Jupiters Congresso SAIt, Teramo, 8-5-2008
Transits: HD17156b Barbieri et al. (2007, A&A, in press): The longest period (21.2 d) and most eccentric (e=0.67) transiting planet Rossiter effect from SARG radial velocities: orbit of planet is coplanar with stellar rotation Decisive contribution by Italian amateur Astronomers for the photometric part Congresso SAIt, Teramo, 8-5-2008
Transits: RATS (RAdial velocities and Transit Search) • Collaboration: INAF (PD, CT, NA, PA), Un. Padova (Astronomy and Physics Dept.), and ESA • Goal: search of giant planet transits and spectroscopic characterization • Intruments: • Schmidt 67/92 cm: FoV~1 square degree • Copernico Telescope • Open to collaborations with amateurs Congresso SAIt, Teramo, 8-5-2008
Transit survey approved for GTO bright time on VST PI: Snellen (Leiden Observatory) Italian Participation: INAF-OA Capodimonte INAF-OAPD OmegaTranS will make use of the Omegacam CCD camera on the newly built VLT 2.6m survey Telescope (operational early 2009) The CCD camera OmegaCAM is a 1 square degree wide field, optical, 16k X 16k camera for the VLT Survey Telescope (VST). It consists of 32 low-noise array, resulting in 0.26 arcsecond pixels. It has been build by a consortium of Dutch, Italian, and German institutes. Congresso SAIt, Teramo, 8-5-2008
Observing strategy At first instance, 3 weeks of bright GTO time (plus additional time that will be persued through GO rounds) will be used to monitor 4 densely populated star fields towards the galactic disk at low declination. Cycle time will be approximately 8.5 minutes, with 20 sec. exposures - targeting about ~200,000 F,G, and K dwarf stars at R=13.5-17.5 for at least 1000 epochs during the first observing season. Data Processing The data reduction will be performed in the (hardware and software) framework of AstroWise, using difference imaging. The expected data flow is 3.5 Tbyte per year (1.5 Tb per partner), well within the capacity of AstroWise. Congresso SAIt, Teramo, 8-5-2008
Transits: PLATO A proposed satellite for ESA Cosmic Vision, Approved for Phase A PI: Català (LESIA) Italian participation: Congresso SAIt, Teramo, 8-5-2008
PLATO PLATO limit Congresso SAIt, Teramo, 8-5-2008
Comparison between PLATO, CoRoT and Kepler Congresso SAIt, Teramo, 8-5-2008
Astrometric detection: GAIA Congresso SAIt, Teramo, 8-5-2008
Exoplanets Direct Imaging from Ground: SPHERE for VLT Congresso SAIt, Teramo, 8-5-2008
The niche of direct detection • Definition of outer parts of the systems (from the snowline outward, 3-40 AU) crucial to understand formation mechanisms of planetary systems • Indirect methods are not efficient at large separations: • Radial velocity signal very small • Transits too rare and inefficient • Astrometry very slow • Microlensing very rare • Direct detection is efficient: • For young giant planets if contrast is ~106-107 • For rocky planets in the habitable zone and old giant planets near the snow line if contrast is ~109 • Direct detection allows planet characterization Congresso SAIt, Teramo, 8-5-2008
Current limits at large separations • Nielsen et al. 2007 Congresso SAIt, Teramo, 8-5-2008
SPHERE Planet Finder for VLT, with the goal of direct detection of extrasolar planets Very challenging goal: need high contrast at small separation from bright stars A brief history: 2 feasibility studies in 2002-2003: VLT-PF (LAOG) and CHEOPS (MPIA, including OAPD) 2004 merging of the projects Fall 2007: PDR Schedule: FDR end 2008 Commissioning: fall 2010 Congresso SAIt, Teramo, 8-5-2008
Reduce WFE and diffraction pattern Allow differential Imaging SPHERE Concept Congresso SAIt, Teramo, 8-5-2008
IFS • Instrument control software (resp. A. Baruffolo) • Science (Survey) • ~17% of FTE Consortium P.I. J.L. Beuzit (LAOG) CNRS/LAOG (Grenoble, F) CNRS/LAM (Marseille, F) CNRS/LESIA (Paris, F) CNRS/LUAN (Nice, F) ONERA (Paris, F) INAF/Padova Observatory (I) MPIA (Heidelberg, D) Observatoire de Genève (CH) ETH (Zürich, CH) NOVA (Amsterdam, NL) ASTRON (Amsterdam, NL) 260 GTO nights Congresso SAIt, Teramo, 8-5-2008
Performances Contrast of 16 mag at 0.5 arcsec from a J=5 star Improvement of 2 orders of magnitude with respect to current instrumentation AO mag limit R=9 Congresso SAIt, Teramo, 8-5-2008
Science Objectives • Directly detect photons from extrasolar giant planets • Explore the mass-period distribution (1-20 Mjup, 1-1000 years) • Survey an extended number of stars • First order characterization of the atmosphere (clouds, dust content, methane, water absorption, effective temperature, radius, dust polarization) Understand the planetary system origins Congresso SAIt, Teramo, 8-5-2008
Science Objectives Direct-imaging of planets: large masses, towards long periods, young/nearby systems • Complementarity in • MASS • AGE • PERIOD RV-transit planets: old/quiet stars, short periods, towards low masses Congresso SAIt, Teramo, 8-5-2008
Number of detected planets • Few tens planet detections expected Congresso SAIt, Teramo, 8-5-2008
EPICS • EPICS is an instrument project for the direct imaging and characterization of extra-solar planets with the European ELT • The eXtreme Adaptive Optics (XAO) system • The Diffraction Suppression System (or coronagraph) • The Speckle Suppression System • The Scientific Instrument(s) • Integral Field Spectroscopy • Differential Polarimetry • A speckle coherence-based instrument • Data processing strategy Congresso SAIt, Teramo, 8-5-2008
EPICS PHASE AConceptual Design • 24 months (Kick Off meeting Oct. ’07) • Consortium: • ESO, LAOG, LESIA, LUAN, LAM, ONERA, Oxford, INAF-Padova, ETH, UvA, ASTRON, UU Congresso SAIt, Teramo, 8-5-2008
EPICS PHASE AWork Breakdown Structure Italian involvement: FTE: 1.35 staff + 2.0 FTE project Money: 81 kEuro (32 kEuro ESO + 49 kEuro FP7) Congresso SAIt, Teramo, 8-5-2008
EPICS Science Objectives Terrestrial Planets in HZ • Some chance for the ~70 M dwarfs (-53<Dec<7) closer than 10pc (HZ at 10 pc is at 15mas, probably beyond inner working angle) • However, tidal locking, atmosphere evaporation, likely thin (Lissauer) or no (Brain) atmosphere • Some chance for rocky planets inwards of HZ (Venus) for the ~100 G, K and M stars within 10pc • Improbable to detect even for the handful of closest K-and and G-stars • Little hope for spectroscopy at R>20 Congresso SAIt, Teramo, 8-5-2008
Detection of rocky planets 10 pc 5 pc 50 pc 20 pc Congresso SAIt, Teramo, 8-5-2008
EPICS Science Objectives Giant Planets, unique science • Young self-luminous gaseous planets in star forming regions or young associations • EPICS can achieve good resolution even for star forming regions at ~100pc, young planets at >3 AU can be detected, very important observation to understand planet formation • Mature giant planets at orbital distances between ~5 and 15 AU in the solar neighbourhood ( 20 pc) • Not an easy observation • Determine frequency and mass distribution of giant planets • Warm Jupiters that have been discovered by radial velocity searches • Fairly easy, spectral characterization • Understand giant planets’ atmosphere composition and structure Congresso SAIt, Teramo, 8-5-2008
EPICS Science Objectives Giant planets from RV surveys Congresso SAIt, Teramo, 8-5-2008