MERLIN observations of bipolar outflow from HM Sagittae

MERLIN maps of HM Sagittae at 6 cm and 18 cm wavelengths are presented. At 6 cm, the inner nebula has been mapped at a resolution of 60 milli-arcsec, revealing two parallel ridge structures to the north and south of a deep central minimum. In addition, these central features are surrounded by a complex, weak structure. The ridges and many of the weak features are correlated with ultra-violet (UV) structure observed with the Hubble Space Telescope (HST). The 18 cm map reveals elongated structure to the east and west of the star's position. There is strong evidence that the east and west edges of this extension are non-thermal. The E-W and N-S features are associated with components detected with optical spectroscopy. The radial velocities of these components suggest that the E-W features are a high velocity bipolar outflow.