Ha spectropolarimetry of the Be supergiant GG Carinae

摘要

We study the geometry of the circumstellar environment of the Be supergiant star GG Car.Methods. We present observations acquired using the IAGPOL imaging polarimeter in combination with the Eucalyptus-IFU spec-trograph to obtain spectropolarimetric measurements of GG Car across Ha at two epochs. Polarization effects along the emissionline are analysed using the Q–U diagram. In particular, the polarization position angle (PA) obtained using the line effect is able toconstrain the symmetry axis of the disk/envelope.