GREGOR

GFPI Calibration Data on 2014-08-23


Overview of GFPI Level 1.0 and Level 0.0 data.

Prj_Type=FPI_Date=20140823_Time=073349

Dark Frames

Narrow-Band Dark Frames


Average narrow-band dark frame (36 single exposures with an exposure time of 80 ms) taken at 10:27:48 UT. The image was scaled between the 0.1% and 99.9% values of the intensity distribution.

Image Statistics Value
Minimum 68.72
Mean 72.92
Maximum 94.53
Variance 0.44
Standard Deviation 0.66
Mean Absolute Deviation 0.50
Skewness -0.53
Kurtosis 4.89

Broad-Band Dark Frames


Average broad-band dark frame (36 single exposures with an exposure time of 80 ms) taken at 10:27:48 UT. The image was scaled between the 2% and 98% values of the intensity distribution.

Image Statistics Value
Minimum 51.75
Mean 53.55
Maximum 70.47
Variance 0.70
Standard Deviation 0.84
Mean Absolute Deviation 0.49
Skewness 3.65
Kurtosis 19.90

Narrow-Band Dark Frames


Average narrow-band dark frame (84 single exposures with an exposure time of 80 ms) taken at 10:28:00 UT. The image was scaled between the 0.1% and 99.9% values of the intensity distribution.

Image Statistics Value
Minimum 69.33
Mean 73.03
Maximum 94.94
Variance 0.32
Standard Deviation 0.56
Mean Absolute Deviation 0.40
Skewness -0.85
Kurtosis 10.22

Broad-Band Dark Frames


Average broad-band dark frame (84 single exposures with an exposure time of 80 ms) taken at 10:28:00 UT. The image was scaled between the 2% and 98% values of the intensity distribution.

Image Statistics Value
Minimum 52.24
Mean 53.56
Maximum 70.14
Variance 0.63
Standard Deviation 0.79
Mean Absolute Deviation 0.43
Skewness 4.26
Kurtosis 24.59

Narrow-Band Dark Frames


Average narrow-band dark frame (36 single exposures with an exposure time of 80 ms) taken at 10:28:21 UT. The image was scaled between the 0.1% and 99.9% values of the intensity distribution.

Image Statistics Value
Minimum 69.08
Mean 73.03
Maximum 95.42
Variance 0.44
Standard Deviation 0.66
Mean Absolute Deviation 0.50
Skewness -0.52
Kurtosis 5.38

Broad-Band Dark Frames


Average broad-band dark frame (36 single exposures with an exposure time of 80 ms) taken at 10:28:21 UT. The image was scaled between the 2% and 98% values of the intensity distribution.

Image Statistics Value
Minimum 51.50
Mean 53.48
Maximum 69.03
Variance 0.70
Standard Deviation 0.84
Mean Absolute Deviation 0.49
Skewness 3.61
Kurtosis 19.59

Flat-Field Frames

Narrow-Band Flat-Field Frames


Average narrow-band flat-field frame (144 single exposures with an exposure time of 80 ms). The image was scaled between the 0.01% and 99.99% values of the intensity distribution.

Image Statistics Value
Minimum 404.99
Mean 561.41
Maximum 593.17
Variance 104.85
Standard Deviation 10.24
Mean Absolute Deviation 6.41
Skewness -4.67
Kurtosis 39.45

Broad-Band Flat-Field Frames


Average broad-band flat-field frame (144 single exposures with an exposure time of 80 ms). The image was scaled between the 0.01% and 99.99% values of the intensity distribution.

Image Statistics Value
Minimum 678.34
Mean 710.87
Maximum 774.91
Variance 62.90
Standard Deviation 7.93
Mean Absolute Deviation 6.08
Skewness 1.09
Kurtosis 2.27

Blue-Shift Map

Blue-Shift Map

Fabry-Pérot etalons results in a blue-shift across the field-of-view (FOV).The blue-shift is derived from the focussed flat-field frames. A second-order polynomial is fitted to the blue-shift map to remove artifacts from dust particles and fringes. Misalignment of the optical and mechnical axes of the etalons leads to a displacement of blue-shift map from the center of the FOV. The minimum of the blue-shift map is indicated by a white cross at [31.02″, 17.33″]. The white contour lines placed 1 pm apart clearly show the increase of the blue-shift towards the periphery of the FOV.

Prefilter Curve

Prefilter

The transmission curve of the prefilter is approximated by a Gaussian (blue), which is fitted to a long spectral scan (red) covering a significant part of the GFPI scan range. The highlighted spectral region refers to the scan range of the science data.

GFPI/FTS Spectra

Long spectral scan (red) after division by the transmission curve of the prefilter. The corresponding spectrum (blue) of the Fourier Transform Spectral (FTS) atlas (Neckel, H., Labs, D. 1984: The Solar Radiation between 3300 and 12500 Å. Solar Physics 90, 205–258, ADS) is shown for comparison. The FTS spectrum was convolved with the approximate transmission profile of the dual-etalon FPI.


Overview of GFPI Level 1.0 and Level 0.0 data.

 

Webpage automatically created with sTools (Kuckein et al. 2017) at 16:51:45 UT on 2017-11-13.

The GREGOR solar telescope was built by a German consortium under the leadership of the Kiepenheuer Institute for Solar Physics in Freiburg with the Leibniz Institute for Astrophysics Potsdam, the Institute for Astrophysics Göttingen, and the Max Planck Institute for Solar System Research in Göttingen as partners, and with contributions by the Instituto de Astrofísica de Canarias and the Astronomical Institute of the Academy of Sciences of the Czech Republic.