Magnetic flux observed over entire solar disk

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Session 123 -- Solar Magnetic Field and Solar Variabilty
Oral presentation, Thursday, 12, 1995, 2:00pm - 3:30pm

[123.06] Magnetic flux observed over entire solar disk

Willam Livingston (NOAO/NSO), Sami Solanki (ETH, Zurich)

A single channel Babock-type magnetograph, using the favorable Fe 1.5648 $\mu$m (g=3) line, reveals fields everywhere from equator to the polar limb. Good seeing is essential. Experimental setup includes a 2.5 arcsec image slicer as the input, the NIM modulator driven at 20Hz, and an exit slit of 0.20\AA. Noise is 5 ($10^{-3}$) percent polarization with a time constant of 3 sec and is negligible. Presumably we mainly sense the intranetwork fields in agreement with S. Martin (1988). New results are that the fields (flux) may strengthen near the limb and that the best signal is obtained at line center. The latter could indicate unresolved doppler shifts or the transverse Zeeman effect. (Both circular and linear polarized light is detected by the modulator). Field strength will be deduced by a statistical analysis of signal vs. position on the line profile.

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