Multiplicity in 5 Msun Stars

Understand

Multiwavelength opportunities have provided important new insights into the properties of binary/multiple 5 Msun stars.

• The combination of cool evolved primaries and hot secondaries in Cepheids (geriatric B stars) has yielded detailed information about the distribution of mass ratios.
• It has also provided a surprisingly high fraction of triple systems.
• Ground-based radial velocity orbits combined with satellite data from Hubble, FUSE, IUE, and Chandra can provide full information about the systems, including the masses.