Rotation of NGC 2264 members

We derive distance-dependent values of sini (where i is the inclination angle) for 97 stars in NGC 2264 from the rotation periods, luminosities, effective temperatures, and projected equatorial rotation velocities, vsini, measured for these stars. We have measured 96 of the vsini values in our sample by analyzing high-resolution spectra with a cross-correlation technique.

We model the observed distribution of sin i for the cluster by assuming that member stars have random axial orientations and by adopting prescriptions for the measurement errors in our sample. By adjusting the distance assumed in the observed sini distribution until it matches the modeled distribution, we obtain a best-fit distance for the cluster. We find the data to be consistent with a distance to NGC 2264 of 913pc.