The VLT-FLAMES Tarantula Survey: Atmospheric Parameters and Nitrogen Abundance for Single and Binary B-type 
Supergiants

Catherine McEvoy, Queen’s University Belfast

Supergiants are massive stars, among the most luminous and influential in the evolution of galaxies. There have been 
numerous model atmosphere analyses of both Galactic and extragalactic supergiants, however, little attention has been given 
to a comparison of the properties of single supergiants and those that are members of multiple systems. Atmospheric 
parameters and Nitrogen abundances have been estimated for all the B-type supergiants in the VLT- FLAMES Tarantula survey. 
These include both targets showing no significant radial velocity variations and binary stars. The estimates have been analysed 
to investigate the impact of binarity on the evolution of massive stars.