Near Infrared Polarimetry of IRAS 19306+1407

Abstract

Polarimetry can be used to observe the dusty outer shells of Post- AGB stars. We can discriminate between the unpolarized light from the central star and the re°ected polarized °ux. The polarisation vectors and polarized °ux can give valuable information on the morphology of the object and the dust grain size distribution. Here we present J and K waveband polarimetry information and modeling of IRAS 19306+1407. We have detected scattered light and high degrees of linear polarisation. In polarized °ux we have detected a `dumbbell' structure, possibly indicating a detached dusty circumstellar envelope (CSE).We have constructed a light scattering model that includes polarisation to investigate the CSE structure in detail.