J/A+A/519/A10 Radial velocity curve of HD 202206 (Couetdic+, 2010) ================================================================================ Dynamical stability analysis of the HD 202206 system and constraints to the planetary orbits. Couetdic J., Laskar J., Correia A.C.M., Mayor M., Udry S. =2010A&A...519A..10C ================================================================================ ADC_Keywords: Stars, double and multiple ; Planets ; Radial velocities Keywords: stars: individual: HD202206 - planetary systems - methods: numerical - techniques: radial velocities - celestial mechanics Abstract: Long-term, precise Doppler measurements with the CORALIE spectrograph have revealed the presence of two massive companions to the solar-type star HD 202206. Although the three-body fit of the system is unstable, it was shown that a 5:1 mean motion resonance exists close to the best fit, where the system is stable. It was also hinted that stable solutions with a wide range of mutual inclinations and low O-C were possible. We present here an extensive dynamical study of the HD 202206 system, aiming at constraining the inclinations of the two known companions, from which we derive possible value ranges for the companion masses. Description: We consider each inclination and one of the longitudes of ascending node as free parameters. For any chosen triplet of these parameters, we compute a new fit. Then we study the long-term stability in a small (in terms of O-C) neighborhood using Laskar's frequency map analysis. We also introduce a numerical method based on frequency analysis to determine the center of libration mode inside a mean motion resonance. The best orbital solution for the HD202206 is: ------------------------------------------------------------- V0 [km/s] 14.729 +/- 0.001 ------------------------------------------------------------- Inner planet Outer planet ------------------------------------------------------------- P [d] 256.389+/-0.044 1397.445+/-19.056 K [m/s] 564.82+/-1.42 38.08+/-1.21 e 0.431+/-0.001 0.104+/-0.024 a [AU] 0.8053 2.4832 i [deg] 90 90 m [MJup] 16.59 2.179 ------------------------------------------------------------- Objects: ------------------------------------------------ RA (2000) DE Designation(s) ------------------------------------------------ 21 14 57.8 -20 47 21 HD 202206 = HIP 104903 ------------------------------------------------ File Summary: -------------------------------------------------------------------------------- FileName Lrecl Records Explanations -------------------------------------------------------------------------------- ReadMe 80 . This file hd202206.dat 31 92 Radial velocity taken with CORALIE spectrograph -------------------------------------------------------------------------------- See also: J/A+A/390/267 : The CORALIE survey for extrasolar planets. VIII (Udry+, 2002) Byte-by-byte Description of file: hd202206.dat -------------------------------------------------------------------------------- Bytes Format Units Label Explanations -------------------------------------------------------------------------------- 1- 14 F14.6 d JD Julian Date of Observation 16- 23 F8.5 km/s RV Radial Velocity of the star 25- 31 F7.5 km/s e_RV Radial Velocity error -------------------------------------------------------------------------------- Acknowledgements: Jacques Laskar, laskar(at)imcce.fr ================================================================================ (End) Patricia Vannier [CDS] 08-Apr-2010