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  Three Neptune-mass planets around HD 69830


  Last update: November the 10th 2006


  • An extrasolar planetary system with three Neptune-mass planets
    C. Lovis, M. Mayor, F. Pepe, Y. Alibert, W. Benz, F. Bouchy, A.C.M. Correia, J. Laskar, C. Mordasini, D. Queloz, N.C. Santos, S. Udry, J.-L. Bertaux, J.-P. Sivan, 2006
    Nature 441, 305     (ADS)
  • Formation and structure of the three Neptune-mass planets system around HD 69830
    Y. Alibert, I. Baraffe, W. Benz, G. Chabrier, C. Mordasini, C. Lovis, M. Mayor, F. Pepe, F. Bouchy, D. Queloz, S. Udry, 2006
    A&A 455, L25     (ADS)
  • ESO Press Release


    •  


    HARPS phase-folded radial velocities:
    a: HD 69830 b (RV signal from planets c & d removed)
    b: HD 69830 c (RV signal from planets a & d removed)
    c: HD 69830 d (RV signal from planetsa & b removed)
    Larger image (307 kb)
     
    HARPS temporal velocities:
    a,b:  Close-up views of the HARPS data (red dots).
    The solide line shows the fitted 3-Keplerian orbital
    solution. c:  Long period signal: the contributions
    from the planets b & c were substracted and
    the data binned (1 RV point per observing run).
    Larger image (181 kb)
     
     
     

    Dynamical study of the HD 69830 system:
    Face-on view of the system (view centered on the central star)
    The black solid lines show the present orbital solution. Each
    colour dot shows the position of the planet every 50000 years.
    The system was shown to be stable for at least 1 Gyr.
    Larger image (290 kb)


  • 3-Keplerian orbital solution (from Lovis et al. 2006):

    Object
    Period
    (days)
    T0
    (JD - 2 400 000)
    Eccentricity
    Omega
    (deg)
    K1
    (m/s)
    m2sini
    (M_Earth)
    a
    (AU)
    N
    Residuals
    (m/s)
    HD 69830 b
    8.667 +/- 0.003
    53496.8 +/- 0.6
    0.10 +/- 0.04
    340 +/- 26
    3.51 +/- 0.15
    10.2
    0.0785
    74
    0.81
    HD 69830 c
    31.56 +/- 0.04
    53469.6 +/- 2.8
    0.13 +/- 0.06
    221 +/- 35
    2.66 +/- 0.16
    11.8
    0.186
    "
    "
    HD 69830 d
    197 +/- 3
    53358 +/- 34
    0.07 +/- 0.07
    224 +/- 61
    2.20 +/- 0.19
    18.1
    0.630
    "
    "



  • Stellar properties:

    Parameter
    Value
    Reference
    Sp. Type
    K0V
    Hipparcos
    pi (mas)
    79.48
    Hipparcos
    d (pc)
    12.58
    Hipparcos
    m_v (mag)
    5.95
    Hipparcos
    B-V (mag)
    0.754
    Hipparcos
    T_eff (K)
    5385 +/- 20
    Lovis et al. 2006
    M_v (mag)
    5.45
    -
    L (L_sol)
    0.60 +/- 0.03
    Lovis et al. 2006
    log(g) (CGS)
    -
    -
    M_1 (M_sol)
    0.86 +/- 0.03
    Lovis et al. 2006
    log(R'HK)
    -4.97
    Lovis et al. 2006
    P_rot (d)
    -
    -
    Vsini (km/s)
    1.1 +0.5/-1.1
    Lovis et al. 2006
    Age (Gyr)
    4-10
    Lovis et al. 2006
    [Fe/H]
    -0.05 +/- 0.02
    Lovis et al. 2006

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    stephane.udry@obs.unige.ch