Northern Galactic OB stars vsini

Accurate and reliable measurements of projected rotational velocities in large samples of OB stars are crucial to confront the predictions of stellar evolutionary models with observational constraints. We reassess previous determinations of projected rotational velocities (vsini) in Galactic OB stars using a large, high-quality spectroscopic dataset and a strategy that accounts for other sources of line-broadening in addition to rotation.

We present a versatile and user-friendly IDL tool - based on a combined Fourier transform (FT) + goodness-of-fit (GOF) methodology - for the line-broadening characterization in OB-type stars. We used this tool to (a) investigate the impact of macroturbulent and microturbulent broadenings on vsini measurements, and (b) determine vsini and the size of the macroturbulent broadening (v_m_) in a sample of ~200 Galactic OB-type stars.