Preparation of a Dual Wavelength Sequence of High-resolution Solar Photospheric Images Using Phase Diversity

Two dual-wavelength sequences of high-resolution solar photospheric images captured over several hours and restored by use of phase diversity

The collection, seeing compensation, and temporal filtering of two high-resolution time-sequences of solar photospheric images are described. 44 80 image sequences of co-spatial and co-temporal 430.5 nm G band and 436.4 nm continuum filtergrams, were obtained with the 47.5 cm Swedish Vacuum Solar Telescope. One data set covers 5 hours of photospheric evolution; the other covers 8 hours. The fie...

Segmentation of Photospheric Solar Images by Using c-Means,k-Means, and FCM Algorithms

Oscillations and running waves observed in sunspots ? II . Photospheric waves

To continue our study of waves related to sunspots in the photosphere, we analyzed CCD, high resolution sunspot observations obtained in the Fe i 557.6 nm line. We produced " time slice images " which reveal inward slow propagating waves in the photospheric penumbra and outward propagating waves in the area around the sunspot. The phase velocity of the waves is near 0.5 km s −1 in both cases an...

Phase diversity restoration of sunspot images

We investigate the dynamics of and the relations between small-scale penumbral and photospheric features near the outer penumbral boundary: penumbral grains (PGs), dark penumbral fibrils, granules, and photospheric G−band bright points. The analysis is based on a 2 h time sequence of a sunspot close to disc center, taken simultaneously in the G−band and in the blue continuum at 450.7 nm. Observ...

Small-scale topology of solar atmosphere dynamics IV. On the relation of photospheric oscillations to meso-scale flows

We use a high quality five-hour sequence of images of the solar photosphere taken at the Swedish Solar Vacuum Telescope, La Palma, to study the relation of meso-scale divergence with the amplitudes of photospheric intensity oscillations. Meso-scale flows are determined by local correlation tracking of the granulation. Statistical evaluation of the co-location probability of regions with more th...