2013MNRAS.431..502S

A direct observation of the spiral structure of the Galaxy is hindered by our position in the middle of the Galactic plane. We propose a method based on the analysis of the birthplaces of high Galactic latitude runaway stars to map the spiral arms and determine their dynamics. As a proof of concept, the method is applied to a local sample of early-type stars and a sample of runaways stars to obtain estimates of the pattern speed (Ωp, local = 20.3±0.5kms-1kpc-1 and Ωp, runaway = 21.9±8.6kms-1kpc-1) and the spiral arm's phase angle (φlocal = -53^○_.1 ± 3^○_.1 and φrunaway = -63^○_.5 ± 22^○_.5). We also estimate the performance of this method once the data gathered by Gaia, in particular for runaway stars observed on the other side of the Galaxy, are available.