The IACOB project

The empirical distribution of projected rotational velocities (vsini) in massive O-type stars is characterized by a dominant slow velocity component and tail fast rotators. Binary interaction has been proposed to play role the formation this tail. We perform complete homogeneous search for signatures binarity sample 54 fast-rotating with aim evaluating hypothesis. This working extracted from larger 415 Galactic which covers full range vsini values. use new archival multi-epoch spectra order detect spectroscopic binary systems. complement information Gaia proper motions TESS photometric data aid identification runaway eclipsing binaries, respectively. identified fraction single-lined (SB1) systems apparently single among $\sim$18% $\sim$70%, When comparing these percentages those corresponding slow-rotating we find that our rotators slightly percentage SB1 ($\sim$18% vs. $\sim$13%) considerably smaller clearly detected SB2 (8% 33%). Overall, there seems be clear deficit binaries (SB1+SB2) ($\sim$26% $\sim$46%). On contrary, significantly higher domain ($\sim$33-50%) than < 200 km/s. Lastly, almost 65% are runaways. Our results seem good agreement idea (with > km/s) mostly populated post-interaction products.