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Roethig, D. T.

Publications and source records attributed to Roethig, D. T..

Lacquer polishing of X-ray optics

Techniques for polishing figured X-ray optics by a lacquer-coating process are described. This acrylic lacquer coating has been applied with an optical quality of an eighth-wave in red light and very effectively covers surface roughness with spatial wavelengths less than about 0.2 mm. Tungsten films have been deposited on the lacquer coatings to provide highly efficient X-ray reflectivity.

Catura, R. C.↗

The Lockheed OSO-8 program. Analysis of data from the mapping X-ray heliometer experiment

The final report describes the extent of the analysis effort, and other activities associated with the preservation and documentation of the data set are described. The main scientific results, which are related to the behavior of individual solar activity regions in the energy band 1.5 - 15 keV, are summarized, and a complete bibliography of publications and presentations is given. Copies of key articles are also provided.

Acton, L. W.↗

Early evolution of an X-ray emitting solar active region

The birth and early evolution of a solar active region has been investigated using X-ray observations from the mapping X-ray heliometer on board the OSO-8 spacecraft. X-ray emission is observed within three hours of the first detection of H-alpha plage. At that time, a plasma temperature of four million K in a region having a density on the order of 10 to the 10th power per cu cm is inferred. During the fifty hours following birth almost continuous flares or flare-like X-ray bursts are superimposed on a monotonically increasing base level of X-ray emission produced by the plasma. If the X-rays are assumed to result from heating due to dissipation of current systems or magnetic field reconnection, it may be concluded that flare-like X-ray emission soon after active region birth implies that the magnetic field probably emerges in a stressed or complex configuration.

Wolfson, C. J.↗

Evolution of the X-ray emitting corona preceding and after major solar events

Soft X-ray emission from the sun during STIP Interval II, observed with the Lockheed Mapping X-ray Heliometer on the NASA OSO-8 satellite, is presented. In examining the emission versus time for extended intervals around the times of the Class 1B flare on March 28, 1976, and the Class 1B flare on April 30, 1976, we find significantly more low level flare activity prior to the major flares than after. Twelve modest X-ray bursts are investigated and no compelling case of a preflare brightening phase is observed. Preliminary correlations with the time history of emitted solar particles are discussed.

Wolfson, C. J.↗

A focussing X-ray collector and its response in flight

A singly focussing X-ray reflector system designed for rocket observation of cosmic X-ray sources is described. The reflector has an angular resolution of one arc minute in X-rays. Focussing properties of this reflector as measured in the laboratory with X-rays and visible light are discussed and the response observed as the flight instrument was scanned over the galactic X-ray source, Sco X-1, is presented.

Catura, R. C.↗

Rocket study of the X-ray background

The X-ray optical detection system flown on Aerobee 17.08 is described in detail, and the preliminary results of the 24 June 1971 flight are discussed. The optical design, fabrication and parabolic nature of the mirrors, effective aperture of mirror array, and X-ray detectors are considered. Preliminary analysis of data from the flight confirms the extended nature and complex structure of the X-ray source in Virgo. A core of X-ray emission is indicated which is approximately 0.5 deg in diameter and surrounded by an emitting region at least 2 deg across. The Virgo source spectrum is observed to have few low energy photons.

Fisher, P. C.↗

X-ray photometry of M1

M1 X ray emission, examining energy interval and power law spectral distribution

Acton, L. W.↗

X-ray spectra of several cosmic sources.

X-ray spectral distributions and fluxes in low kev range of five cosmic sources at low galactic latitude and longitude, noting effective temperature

RADIATION DETECTOR↗