PI: Elliott Horch, Southern Connecticut State University, email@example.com
Address: Department of Physics, 501 Crescent Street, New Haven, CT 06515, USA
CoI: Robert Mathieu, University of Wisconsin-Madison
CoI: Aaron Geller, Northwestern University
Title: A Multiplicity Survey of M35 and M67 with the Differential Speckle Survey Instrument
Abstract: The open clusters M35 and M67 are reasonably close together on the sky but represent a large difference in age. Both are at a distance of approximately 800 pc, making their members somewhat fainter than what has generally been considered interesting for speckle imaging techniques at mid-sized telescopes. However, the WIYN Telescope currently has the Differential Speckle Survey Instrument in residence, a two-channel speckle imaging system that provides high-quality diffraction-limited images and color information with a limiting magnitude of ~15. We propose to use this unique capability to survey all cluster members of M35 and M67 to 14th magnitude and known spectroscopic binaries to 15th magnitude in order to detect companions with projected physical separations as small as 32 AU for stars fainter than V=10.5 and as small as 8 AU for those brighter than V=10.5 (using the sub- diffraction-limited capabilities of DSSI). This will be complementary to previous spectroscopic work on these clusters at WIYN and will dramatically increase our knowledge of the binary and multiple star populations across ~8 decades in period, including both the dynamically hard and soft systems. The comparison between the two clusters will give a clear indication of whether triples form primordially and to what extent, as well as the evolution of wide binary and triple statistics with age.
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