Extrasolar Planet Observational Studies: The Italian Contribution

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Extrasolar Planet Observational Studies The
Italian Contribution

• Raffaele Gratton
• INAF Osservatorio Astronomico di Padova

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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
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Main Programs in Italy

• Search for planets
• High precision radial velocities
• SARG Planets in binaries
• SARG Search for Hot Neptunes
• Planets around giant stars
• Time delays
• The case of V391 Pegasi
• Transits
• Search for planets in open clusters
• HD 17156b
• RATS
• OmegaTrans
• Plato

• High contrast imaging
• SPHERE for VLT
• EPICS for ELT
• Planetary formation
• Disks
• From Planetesimals to planets
• Orbit stability

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V391Peg
SPHERE
Red Giants
Open Clusters
EPICS
SARG
RATS
PLATO
GAIA
OTrans
M. Perryman, 2001 (from http//www.obspm.fr/encyc
l/searches.html)
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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) AA
462,345 Martinez Fiorenzano et al. (2005) AA
442,775
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SARG Planets in binaries
May planets form in close binaries? There are
less planets in close binaries
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SARG Planets in binaries

• 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)

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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

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SARG Determine the frequency of Hot Neptunes

• Intensive program 60 nights/yr for two years at
  TNG
• 26 nights allocated at TNG for AOT17

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First results requested accuracy (1-2 m/s)
achieved
Candidates from lower accuracy program at
McDonald Observatory
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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 gt10 planets discovered

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Planets around Red Giants - 2

• Massive planets around massive stars are common
  (gt10 of the stars)

Mlt1.1 Mo
Mgt1.1 Mo
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Planets around Red Giants - 3

• No correlation between presence of planets and
  metallicity, at variance with results G-K main
  sequence stars

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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

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Transits Open clusters

• PI Piotto (Univ. PD)
• Un. PDINAF-OAPD
• Do planets form also in dense environments?
• Small statistics ? Metal-rich open clusters
• NGC6791
• 10 nights at CFHTSan Pedro MartirLoiano
• NGC6253
• 10 nights at WFI_at_La SillaAAT

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Transits Open clusters

• Highly accurate photometric curves (error of a
  few thousandths of mag for the upper MS)

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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
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Transits TReS and HATP survey

• Italian participant A. Sozzetti (OATO)
• Publications
• Observational Tests of Planet Formation Models
  (ArXiv07110409)
• HAT-P-4b A metal-rich low-density transiting hot
  Jupiter (ArXiv07100602)
• TrES-4 A Transiting Hot Jupiter of Very Low
  Density (ArXiv07080834)
• HAT-P-3b A heavy-element rich planet transiting
  a K dwarf star (ArXiv07074267)
• TrES-3 A Nearby, Massive, Transiting Hot Jupiter
  in a 31-Hour Orbit (ArXiv07052004)
• HD147506b A Super-Massive Planet in an Eccentric
  Orbit Transiting a Bright Star (ArXiv07050126)
• Improving Stellar and Planetary Parameters of
  Transiting Planet Systems The Case of TrES-2
  (ArXiv07042938)
• The Transit Light Curve Project. VI. Three
  Transits of the Exoplanet TrES-2 (ArXiv07042907)
• TrES-2 The First Transiting Planet in the Kepler
  Field (astro-ph/06099335)
• A Keck/HIRES Doppler Search for Planets Orbiting
  Metal-Poor Dwarfs. I. Testing Giant Planet
  Formation and Migration Scenarios
  (astro-ph/0605067)

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• 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 Teff585050 K, log g4.40.1, and
  Fe/H-0.150.10.
• New method to derive mass and radius of the star
  
• M? 0.9800.062 Mo
• R?1.0000.034 Ro
• Age 5.12.5 Gyr
• Mp1.1980.053 MJ
• Rp1.2200.044 RJ,
• ? TrES-2 is the most massive among the currently
  known nearby transiting hot Jupiters

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Transits HD17156b

• Barbieri et al. (2007, AA, in press)
• The longest period (21.2 d) and most eccentric
  (e0.67) 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

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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 FoV1 square degree
• Copernico Telescope
• Open to collaborations with amateurs

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• 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.

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• 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 R13.5-17.5 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.

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Transits PLATO
A proposed satellite for ESA Cosmic Vision,
Approved for Phase A PI Català (LESIA)
Italian participation
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(No Transcript)
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PLATO
PLATO limit
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Comparison between PLATO, CoRoT and Kepler
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Astrometric detection GAIA
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Exoplanets Direct Imaging from Ground SPHERE for
VLT
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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

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Current limits at large separations

• Nielsen et al. 2007

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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
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SPHERE Concept
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Consortium
P.I. J.L. Beuzit (LAOG)
INAF/Padova Observatory (I) MPIA (Heidelberg,
D) Observatoire de Genève (CH) ETH (Zürich, CH)
NOVA (Amsterdam, NL) ASTRON (Amsterdam, NL)
CNRS/LAOG (Grenoble, F) CNRS/LAM (Marseille,
F) CNRS/LESIA (Paris, F) CNRS/LUAN (Nice,
F) ONERA (Paris, F)
260 GTO nights
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Performances
Contrast of 16 mag at 0.5 arcsec from a J5 star
Improvement of 2 orders of magnitude with
respect to current instrumentation
AO mag limit R9
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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

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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
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Number of detected planets

• Few tens planet detections expected

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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

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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

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EPICS PHASE AWork Breakdown Structure
Italian involvement FTE 1.35 staff 2.0 FTE
project Money 81 kEuro (32 kEuro ESO 49 kEuro
FP7)
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Terrestrial Planets in HZ
EPICS Science Objectives

• Some chance for the 70 M dwarfs (-53ltDeclt7)
  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 Rgt20

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Detection of rocky planets
10 pc
5 pc
50 pc
20 pc
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Giant Planets, unique science
EPICS Science Objectives

• 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 gt3 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

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Giant planets from RV surveys
EPICS Science Objectives