Near-Sun observations of an F-corona decrease and K-corona fine structure.

Remote observations of the solar photospheric light scattered by electrons (the K-corona) and dust (the F-corona or zodiacal light) have been made from the ground during eclipses and from space at distances as small as 0.3 astronomical units to the Sun. Previous observations of dust scattering have not confirmed the existence of the theoretically predicted dust-free zone near the Sun.

Modulation transfer function measurement technique for small-pixel detectors.

A modulation transfer function (MTF) measurement technique suitable for large-format, small-pixel detector characterization has been investigated. A volume interference grating is used as a test image instead of the bar or sine wave target images normally used. This technique permits a high-contrast, large-area, sinusoidal intensity distribution to illuminate the device being tested, avoiding the need to deconvolve raw data with imaging system characteristics.

Ultraviolet photoresponse characteristics of diamond diodes.

Thep hotoresponseo f Schottkya nd np-diamondd iodes has been measured from 120 to 600 nm. The ultraviolet response is 100 times the visible response.

Ultraviolet observations of solar fine structure.

The High Resolution Telescope and Spectrograph was flown on the Spacelab-2 shuttle mission to perform extended observations of the solar chromosphere and transition zone at high spatial and temporal resolution. Ultraviolet spectroheliograms show the temporal development of macrospicules at the solar limb. The C IV transition zone emission is produced in discrete emission elements that must be composed of exceedingly fine (less than 70 kilometers) subresolution structures.