The infrared void in the Lupus dark clouds revisited: a polarimetric approach

The results of B-band CCD imaging linear polarimetry obtained for stars from the Hipparcos catalogue are used to re-examine the distribution of the local interstellar medium towards the IRAS 100-mu m emission void in the Lupus dark clouds. The analysis of the obtained parallax-polarization diagram assigns to the dark cloud Lupus 1 a distance between 130 and 150 pc and assures the existence of a low column density region coincident with the observed infrared void. Moreover, there are clear indications of the existence of absorbing material at distances closer than 60-100 pc, which may be associated with the interface boundary between the Local Bubble and its neighbourhood Loop I superbubble.