Identification of Moving Groups and Member Selection using Hipparcos Data

Abstract

A new method to identify coherent structures in velocity space --- moving groups --- in astrometric catalogues is presented: the Spaghetti method. It relies on positions, parallaxes, and proper motions and is ideally suited to search for moving groups in the Hipparcos Catalogue. No radial velocity information is required. The method has been tested extensively on synthetic data, and applied to the Hipparcos measurements for the Hyades and IC2602 open clusters. The resulting lists of members agree very well with those of Perryman et al. for the Hyades and of Whiteoak and Braes for IC2602.