event
Thursday 21 Jun 2012: SUSI Multiplicity Survey of Sco-Cen
Aaron Rizutto - Macquarie University, Sydney
Physics, 4th floor 14:00-14:30
Multiplicity properties of recently formed stars can provide valuable insight into the understanding of star formation mechanisms. For more than a decade it has been widely accepted that at least half of all stars form in binary pairs, though their role in, for example, the redistribution of angular momentum during star formation, is still poorly understood. The Sco-Cen OB Association is the nearest region to the sun with recent massive star formation. We have used the Sydney University Stellar Interferometer to undertake the first multiplicity dedicated long-baseline interferometric survey. We observed 69 stars brighter than 5th visual magnitude and bluer that B-V = -0.1 in the Sco-Cen region of sky. Our survey was capable of detecting binary companions with separations ranging from 7 to 200 mas and contrasts smaller than 3.6 magnitudes. We found companions to be associated with 20 of the targets, five of these were previously undetected companions. With follow-up observations to fit orbital parameters, we can produce the most accurate age estimation of the Sco-Cen subgroups to date.
