Thermal Defocus of F/1.14 Parabolic 8.4 meter Primary Mirror of the Large Binocular Telescope
"8.4 meter LBT primary mirrors should experience around 40 microns of thermal defocus per 1 Kelvin." - Buddy Martin, Ph.D.
"Because the prime-focus LBCs are at a fast f/1.47 beam, the image quality is very sensitive to changes, to the mirror and steel temperatures, for example." - Olga Kuhn
The 8.4 meter primary mirrors are highly sensitive to thermal fluctuations. This is a problem. Sad face.
2021.03.29 Dataset
Figures
Average Faceplate to Backplate Thermal Difference 3 Hour Period
Thermal Defocus of F/1.14 Parabolic 8.4 meter Primary Mirror of the Large Binocular Telescope
"8.4 meter LBT primary mirrors should experience around 40 microns of thermal defocus per 1 Kelvin." - Buddy Martin, Ph.D.
"Because the prime-focus LBCs are at a fast f/1.47 beam, the image quality is very sensitive to changes, to the mirror and steel temperatures, for example." - Olga Kuhn
The 8.4 meter primary mirrors are highly sensitive to thermal fluctuations. This is a problem. Sad face.
2021.03.29 Dataset
Figures
Average Faceplate to Backplate Thermal Difference 3 Hour Period
Offline LBCFPIA RMS Z4 (nm)
Offline LBCFPIA PSF Degradation, WIQ (Percentage)
Offline LBCFPIA Estimated Seeing, FWHM (arcsec)
Analysis
Curve Fitting
Glass Fit
Z4 Fit