Analysis of He I 1083 nm Imaging Spectroscopy Using a Spectral Standard

O.V. Malanushenko, H.P. Jones
2004 Solar Physics  
We develop a technique. for the analysis of He I 1083 nm spectra which addresses several difficulties through determination of a continuum background by comparison with a well calibrated standard and through removal of nearby solar and telluric blends by differential comparissri to an average spectrum. The method is compared with earlier analysis of imaging >spectroscopy obtained at the National Solar Okrvatory/Kitt Peak Vacuum Telescope (NSO/KPVT) with the NASA/NSO SpectromagnetGgraph (SPM).
more » ... examine distributions of Doppler velocity and line width as a function of central intensity fcr an active region, filament, quiet Sun, and coronal hole. For our example, we find that line widths and central intensity are oppositely correlated in a coronal hole and quiet Sun. Line widths are comparable to the quiet sun in the active region, are systematically lower in the filament, and extend to higher values in the coronal hole. Outward velocities of M 2 to 4 km/s are typically observed in the coronal hole. The sensitivity of these results to analysis technique is discussed.
doi:10.1023/b:sola.0000036873.75777.33 fatcat:ehs27xphlndvpjwhaat2q7no4u