Future Project of Optical Polarimetry in Northern Hemisphere, SGMAP

Kawabata, K. S. and SGMAP team

We are promoting SGMAP (Search for the Galactic Magnetic-field by All-sky Polarimetry survey) project. The goal of this project is to produce a homogeneous polarimetric catalog of all astronomical objects brighter than 13-14 magnitudes at optical three bands in northern hemisphere, which will be obtained by non-biased observations with a specially-designed wide-field two-channel imaging polarimeter attached to a dedicated 1-m class telescope.  The number of the sample objects will reach more than several millions, which is more than hundred times as large as the sample number of the currently-existing compilation of optical polarimetry (e.g., Heiles 2000). It is still in a fund-raising phase. If this project is realized, the produced catalog will contribute to many fields of astronomy, e.g., Galactic magnetic field (with helps of future Gaia/nano-JASMINE astrometry, radio survey with SKA and so on), interstellar media, mass-losing stars, etc, together with ongoing survey projects as SOUTH POL. The polarization map will also be useful to correct foreground polarization components in extragalactic targets like CMB, searching B-mode polarization pattern,  and AGNs.