Optical polarization of solar type stars with debris disks

GARCÍA, L. H., GOMEZ, M.

REVISTA MEXICANA DE ASTRONOMíA Y ASTROFíSICA

UNIV NACIONAL AUTONOMA MEXICO

Lugar: México; Año: 2015 vol. 51 p. 1 - 10

0185-1101

We report optical aperture polarimetry for 34 southern hemisphere main-sequence stars with debris disks, in addition to 54 stars without evidence of disk. These sets of stars are combined with other of 109 stars from the northern hemisphere, obtained from  the literature, to build two samples of 51 and 97 solar-type stars with and without debris disks. The distributions of polarization values for the samples with and without disks show no significant statistical difference, within the precision of our observations. However, we identify a sub-sample of 9 stars (d less than 50 pc) with disks that have polarization levels above the median for the sample with disk and that are not appropriately reproduced by Serkowski´s interstellar law. These stars are candidates to have intrinsic polarization. In this case the debris disks in these stars may be populated by small dust with sizes of about 0.1 micron.