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Paper: Infrared Stokes Spectro-Polarimeter at the National Astronomical Observatory of Japan
Volume: 437, Solar Polarization Workshop 6
Page: 371
Authors: Hanaoka, Y.; Sakurai, T.; Shinoda, K.; Noguchi, M.; Miyashita, M.; Fukuda, T.; Suzuki, I.; Hagino, M.; Arai, T.; Yamasaki, T.; Takeyama, N.
Abstract: We are now constructing an infrared spectro-polarimeter for the Solar Flare Telescope of NAOJ. It observes the full Sun in two wavelength bands, one near 1.56 μm for highly Zeeman-sensitive spectral lines of Fe I and the other near 10830 Å for He I and Si I lines. The instrument records full Stokes profiles, and a Stokes inversion process will give information on the strength and orientation of the magnetic field vector for both of the photosphere and the chromosphere. The infrared detector we are using is an InGaAs camera manufactured by a Belgian company Xenics. Its format is 640×512 pixels and its read-out speed is 90 frames s-1. The solar disk will be covered by two swaths (the northern and southern hemispheres) of 640 pixels each. The final magnetic maps will be made of 1200×1200 pixels with a pixel size of 1.8 arcsec. Now we are operating regular observations and generate full-disk, full-Stokes maps (a few maps per day). Our ultimate goal is to derive the distribution of magnetic helicity over the whole surface of the Sun, not only in sunspots and active regions.
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