Astronomy and Astrophysics – Astronomy
Scientific paper
May 1997
adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=1997spd....28.0218l&link_type=abstract
American Astronomical Society, SPD meeting #28, #02.18; Bulletin of the American Astronomical Society, Vol. 29, p.896
Astronomy and Astrophysics
Astronomy
Scientific paper
Seeing effects have been corrected in two cospatial and cotemporal 70-minute sequences of images collected in the G-band 4305 Angstroms and wideband 4686 Angstroms. The data were obtained with the 50 cm Swedish Vacuum Solar Telescope on the island of La Palma, Spain. The 29arcsecx 70arcsec field-of-view (FOV) near disk center contains both an enhanced network region and an (apparently) non-magnetic ``quiet'' region of granulation. The mean time between restored frames is 23.5 s. Each of the 180 images is created with Phase-Diverse Speckle (PDS) imaging, using two different focus positions sampled at the best three snapshots of the atmospheric turbulence (seeing) during a 20-second selection window. Wavefronts are estimated for each focused--defocused image pair and a restored frame is produced from all six images. The average resolution in the restored sequence is about 0farcs4 (corresponding to spatial frequencies up to half the diffraction limit of the telescope), which is good enough to allow detection of ~ 0farcs2 bright points. The data is used for statistical measurements of magnetic element speed, interaction frequency, and lifetime (see accompanying poster by T. E. Berger et al). We show destretched and space-time filtered movies of both the G-band and continuum images, as well as raw data to demonstrate the effect of the restoration process. This work was supported by NASA contracts NAS5-30386 at Stanford and NAS8-39747 and Independent Research Funds at Lockheed-Martin. MGL was supported by the Swedish Science Research Council.
Berger Thomas E.
Löfdahl Mats G.
Shine Richard A.
Title Alan M.
No associations
LandOfFree
Phase-Diversity Restoration of two Simultaneous 70-minute Photospheric Sequences. does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Phase-Diversity Restoration of two Simultaneous 70-minute Photospheric Sequences., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Phase-Diversity Restoration of two Simultaneous 70-minute Photospheric Sequences. will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-1146670