Description
We use Gaia DR3 data and the HDBSCAN clustering algorithm to investigate the multidimensional kinematics of the Scorpius OB2 association, also known as the Scorpius–Centaurus (Sco-Cen) association.
Previous studies, de Zeeuw (1999) using Hipparcos data, and Rizzuto et.al., (2013) using the Sydney University Stellar Interferometer indicate a large, coherent stellar structure with unidirectional proper motions in the region between (l, b)(280 to 360, -10 to +30). As part of our ongoing studies, Sco OB2 is investigated to determine the presence of subgroups within this structure. We use 5-dimensional data from the Gaia DR3 Archive, namely ra, dec, parallax, pmra and pmdec, along with the HDBSCAN unsupervised learning algorithm to find coherent clusters within the data.
It is known that the differential rotation of the Milky Way is apparent in the motions of stars within just a few 100 pc, we have therefore removed the peculiar motion of the Sun from observed proper motions in order to obtain a true picture of their motions through space.
We identify diverse coherent groups of stars ranging in size and proper motion throughout the region and determine the common motion of the traditional subgroups within Sco-Cen, namely Upper Scorpius, Upper Centaurus–Lupus and Lower Centaurus–Crux.
