  Optical broad-band polarimetry is presented for near-infrared color-selected
AGN classified QSOs based on their K-band luminosity. More than 10% of a sample
of 70 QSOs discovered in the Two Micron All Sky Survey (2MASS) with J-K > 2 and
M_K < -23 show high broad-band linear polarization (P > 3%), and values range
to a maximum of P = 11%. High polarization tends to be associated with the most
luminous objects at K, and with QSOs having the highest near-IR-to-optical flux
ratios. The 2MASS QSO sample includes objects possessing a wide range of
optical spectral types. High polarization is seen in two of 22 broad
emission-line (Type 1) objects, but 1/4 of the QSOs of intermediate spectral
type (Type 1.5-1.9) are highly polarized. None of the nine QSOs classified as
Type 2 exhibit P > 3%. It is likely that the unavoidable inclusion of
unpolarized starlight from the host galaxy within the observation aperture
results in reduced polarization for the narrow emission-line objects. The high
polarization of 2MASS-discovered QSOs supports the conclusion inferred from
their near-IR and optical colors, that the nuclei of many of these objects are
obscured to some degree by dust. The 2MASS QSO sample is compared to other,
predominantly radio-quiet, QSOs and is found to be consistent with the idea
that the orientation of AGN to the line of sight plays a major role in
determining their observed properties.

Astrophysics