43yr spectrosc. monitoring of the Pleiades region

We gathered 6104 spectra of 377 stars between 1981 and 2021, and merged our radial velocities with 1151 measurements from an independent survey by others started three years earlier. With the combined data spanning more than 43yr, we have determined orbits for some 30 new binary and multiple systems, more than doubling the number previously known in the Pleiades.

The longest period is 36.5yr. A dozen additional objects display long-term trends in their velocities, implying even longer periods. We examine the collection of orbital elements for cluster members, and find that the shape of the incompleteness-corrected distribution of periods (up to 104 days) is similar to that of solar-type binaries in the field, while that of the eccentricities is different.