Abstract
An observing program in the spectral region of the opacity minimum region near 1650 nm was started at NSO/SP–VTT many years ago and few results were presented. Thanks to an image processing unit connected to a rather conventional TV camera, IR images taken at 1650 nm can be displayed on the TV monitor and images stored on a VCR for subsequent comparison with corresponding images in the visible spectrum. This rather qualitative analysis is substantiated thanks to results coming from one–dimensional time series obtained with an IR pin–hole spectrophotometer. Power spectra of the o.m.r. granulation as well as its temporal behaviour are compared with results obtained using the same method in the optical region of the solar spectrum. Noticeable differences are emerging, including the reduced effect of 5-min oscillations.
Publisher
Cambridge University Press (CUP)
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