Astron. Astrophys. 343, 273-280 (1999)

3. The determination of orbital parameters

Describing orbits by:

the expected radial velocities are

where

and is the angular position of the star measured from the centre of mass at a given instant.

Orbital elements have been determined by a least-squares fitting of observed radial velocities to Eq. (1) with the following steps: one degree for , 0.5 km s^-1 for velocities and 0.01 for e. Errors have been estimated as the variation in the parameter which increases the rms deviation of the observed radial velocities with respect to the fitted curve by 1 .

For each star, Table 4 reports the determined orbital elements, their errors and the mass function:

Table 4. Orbital parameters and their errors. Errors are defined as the variation in the parameter which increases by one the observed radial velocity dispersion around the fitting curve.

© European Southern Observatory (ESO) 1999

Online publication: March 1, 1999
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