High-velocity H II regions delineating a central bar in our galaxy ?

Three discrete H II regions have been discovered whose surprisingly high velocities indicate that they may lie in the central bar of our Galaxy. The diameters, densities, masses, and Lyman continuum photon fluxes of the sources were studied. Evidence favoring the existence of a bar is discussed, as are competing models such as the ejection hypothesis. The regions under study have positions and velocities compatible with their being at the periphery of a central bar structure. Late-type stars detected as OH masers may also serve to delineate the bar structure.