First analysis of an OH survey of inner Galaxy: evidence for a stellar Bar

Abstract

Part of a large survey of the inner galactic Plane ( $ | \ell | < 45^{\circ} $ and $ | b | < 3^{\circ} $ total) in the OH 1612MHz line in search for OH/IR stars is analysed. We find strong evidence for a central m=2 distortion based on geometrical considerations. The observed deviation from axisymmetry cannot be explained by lopsidedness and agrees with other recent models of the galactic Bar on length, inclination and axis ratio.