The Astronomical Journal, 155:215 (14pp), 2018 May https://doi.org/10.3847/1538-3881/aab9b8 © 2018. The American Astronomical Society. All rights reserved. Speckle Interferometry of Red Dwarf Stars Brian D. Mason1,6, William I. Hartkopf1,6,8 , Korie N. Miles1,7, John P. Subasavage2,3,6 , Deepak Raghavan4,6, and Todd J. Henry5 1 U.S. Naval Observatory, 3450 Massachusetts Avenue, NW, Washington, DC 20392-5420, USA;
[email protected],
[email protected] 2 U.S. Naval Observatory, Flagstaff, AZ 86001, USA;
[email protected] 3 2310 E. El Segundo Boulevard, El Segundo, CA 90245, USA 4 Center for High Angular Resolution Astronomy, Georgia State University, P.O. Box 3969, Atlanta, GA 30302-3969, Georgia;
[email protected] 5 RECONS Institute, Chambersburg, PA 17201, USA;
[email protected] Received 2017 November 20; revised 2018 March 19; accepted 2018 March 22; published 2018 April 27 Abstract We report high-resolution optical speckle observations of 336 M dwarfs, which results in 113 measurements of the relative position of 80 systems and 256 other stars with no indications of duplicity. These are the first measurements for two of the systems. We also present the earliest measurements of relative position for 17 others. We include orbits for six of the systems, two revised and four reported for the first time. For one of 0.1175 0.0079 the systems with a new orbit, G 161-7, we determine masses of 0.156 ± 0.011 and for the A and B components, respectively. All six of these new calculated orbits have short periods (between fiveand38years) and hold the promise of deriving accurate masses in the near future.