Abstract

Since their discovery over a decade ago (Murcray et al., 1981; Brault and Noyes, 1983), the neutral Magnesium emission lines at 12 microns wavelength have proven to be valuable probes of the Sun's magnetic field. These infrared lines are the most Zeeman-sensitive lines observed in the solar spectrum. These lines arise in the upper photosphere, at around 400 km above the continuum. Our group at Goddard Space Flight Center has used the McMath-Pierce telescope and Fourier transform spectrometer, in combination with two cryogenic infrared postdispersers, developed at Goddard Space Flight Center and Kitt Peak National Observatory, to observe the 12.32-micron line. This program has produced an extensive study of the magnitude and structure of magnetic fields in sunspots and other active regions, as well as in quiet regions.

© 1995 Optical Society of America