Applying speckle-masking to spectra

We have applied the technique of speckle masking to spectra. The obser- vation of elongated solar structures avoids the problem of missing information in one-dimensional spectra. Image motion perpendicular to the slit was diminished by a one-dimensional image stabilization system. The remaining influence of the earth's atmosphere was removed by a modified speckle-masking algorithm, adapted to the single spatial dimension occurring in the spectra. The reconstructed spectra achieve the diffraction limit of the telescope and the spectrograph. The first application of this technique to observations of spicules and penumbral filaments reveals more details and also yield line profiles which differ from those before reconstruction. The Ha emission in spicules shows line-of-sight velocities two times larger than in the unprocessed spectra. The non-magnetic line Fe 709.03 nm shows penumbral line widths, reflecting mostly the line asymmetry from the Ever- shed effect, which are tightly correlated to the continuum intensity fluctuations. Our reconstruction increases the coherence between both from 0.6 to 0.8

Temperature mapping of sunspots and pores from speckle reconstructed three colour photometry

The two-dimensional temperature distribution in a highly structured sunspot and in two small umbrae is determined from a three-colour photometry in narrow spectral continua. Disturbing influences from the earths atmosphere are removed by speckle masking techniques, yielding a spatial resolution limited by the telescopes aperture. The corresponding colour temperatures are consistent over a range of more than 2000 K, although the numerical correction introduced by the reconstruction differs largely for the three colours. Part of the scatter in the temperature relation disappears when convoluting the final images with artificial PSFs that compensate for the different, colour dependent spatial resolution. The remaining spread in the scatter plots does not reflect noise, but is related to local variations of the temperature difference between the continuum emitting layers. This is most obvious for a small umbra which yields branches in the scatter plots the bluer of which corresponding to the limb-side umbral border. Here, the hot rim of a Wilson depressed umbra becomes visible. The temperature map of the large spot shows that the bright umbral dots do not reach the temperature of the non-spot surroundings. Instead, they exceed the 2000K cooler umbral temperature minimum by 900-1300 K. The filamentary structure of the surrounding penumbra has spatial temperature fluctuations of typically 700 K, a value which fits earlier observed ontrasts. However, the mean temperatures of 5650K in the dark and 6250K in the bright penumbral fine structures exceed former findings. Exceptionally bright penumbral grains are 250K than the mean solar surface and thus exceed even brightest granules