Infrared polarization and beaming effect for BL Lac objects

With the idea of the beaming models, we derive a relation between the obser ved polarization and Doppler-corrected magnitude; that is, the observed pol arization is in anti-correlation with the Doppler-corrected magnitude. Maki ng use of the infrared data observed simultaneously by Impey et al. [Mon. N ot. R. Astron. Sec. 200 (1982) 19; 209 (1984) 245] and Holmes et al. [ibid. 210 (1984) 961] we found that: (1) there is a significant correlation betw een the observed maximum polarization and Doppler-corrected magnitude but t he polarization is not in anti-correlation with the Doppler-corrected magni tude; (2) the maximum infrared polarization is strongly correlated with the maximum optical polarization Our conclusion is that the infrared polarizat ion depends only on the degree of ordering of the magnetic held in the sync hrotron emission regions and not on the beaming effect. Both infrared and o ptical emissions originate from the synchrotron radiation.