| Abstract : | Dust polarization observations at optical wavelengths help understand the dust grain properties and trace the plane-of-the-sky component of the magnetic field. In this study, we use the optical polarization data acquired from AIMPOL along with the distances (?) and extinction (?v ) data. We studied the variation of polarization efficiency (?/?v ) as a function of ?v and polarization rate (?/?) versus ? towards five clusters NGC 1931, Stock8, NGC 1960, NGC 1664, and NGC 2281 located towards the anti-center Galaxy. These clusters lie within a 10° radius around the star-forming region NGC 1893, but at different distances. We employ a broken power-law fit and Bayesian analysis on ?/?v versus ?v and ?/? versus ? plots. Our earlier work towards NGC 1893 revealed the presence of two dust populations along the line of sight: (i) foreground dust exhibiting higher polarization efficiency but a lower polarization rate, and (ii) Perseus dust showing a lower polarization efficiency but a slightly higher polarization rate. When the data of other clusters are clubbed together by excluding two clusters, the same trends are present. We conclude that the assumption of similar dust properties and magnetic field orientations as a function of distance and extinction over the larger projected area say a 10-degree diameter of a specific region of interest, may be valid, especially towards NGC 1893.
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