2003A&A...404..775Z

This paper presents an application of the TwO-Dimensional CORrelation (TODCOR) algorithm to multi-order spectra. The combination of many orders enables the detection and measurement of the radial velocities of very faint companions. The technique is first applied here to the case of HD 41004, where the secondary is 3.68mag fainter than the primary in the V band. When applied to CORALIE spectra of this system, the technique measures the secondary velocities with a precision of 0.6km/s and facilitates an orbital solution of the HD 41004B subsystem. The orbit of HD 41004B is nearly circular, with a companion of a 19M_J minimum mass. The precision achieved for the primary is 10m/s, allowing the measurement of a long-term trend in the velocities of HD 41004A.