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Results for “Solar x-ray flares”

Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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At least 55 records · Page 3

A note on the acceleration phase of high-energy particles in the solar flare on 7 July, 1966.

The acceleration phase of solar cosmic rays and relativistic electrons is studied on the basis of the observational data available on the optical, radio, X-ray, and particle events associated with the solar flare that occurred on July 7, 1966. The generating process of hydromagnetic shock waves which excited the type-II radio burst detected at a frequency below about 100 MHz is also discussed. The results of the study suggest that no secondary acceleration process after the explosive phase can contribute much to the generation of high energy particles. The ejection of solar cosmic rays and relativistic electrons seems to be related to the expansion of the magnetic bulge which can trap accelerated electrons from the triggering region of solar flares.

Sakurai, K.↗

The interpretation of XUV solar radiation.

Discussion of the importance of laboratory and theoretical investigations for the analysis of solar UV and X-ray data by referring to five problems to which space experimenters are currently devoting a great deal of attention: (1) the temperature minimum at the interface between the photosphere and the chromosphere; (2) the temperature and density profiles of the low chromosphere; (3) the transition zone at the chromosphere-corona interface; (4) the corona; and (5) solar flares. Brief comments are made on the special need for laboratory and theoretical data of all kinds to assist in the interpretation of the rapidly accumulating volume of observations in the X-ray region of the solar spectrum.

Goldberg, L.↗

A study of two flares on 8 July 1968 in the light of their ionospheric effects.

Detailed study of the observed ionospheric effects of the X-ray flare on July 8, 1968, which was of considerable importance both from the ionospheric and solar physics point of view. The associated optical flare was of importance 3B. The ionospheric effects were examined in order to derive a suitable physical model of flare-induced ionization below 100 km, and hence to estimate the spectral characteristics of the ionizing radiations from the observed SID s. The electron loss coefficients below 70 km height calculated from the formula developed in the analysis are in agreement with available data.

Sengupta, P. R.↗

Solid State Studies of the Radiation Histosy of Lunar Samples

Particle track densities up to greater than 3 x 10(exp 9) per square centimeter have been measured in different samples. Rocks 17, 47, 57, and 58 have VH (Z greater than 22) galactic cosmic ray ages of 11, 14, 28, and 13 x 10(exp 6) years, respectively. Rock 57 has a calculated erosion rate of approximately less than 10(exp -7) centimeter per year. Near-surface track versus depth data in rock 17 can be fit with solar flare particles that have a differential energy spectrum alpha E(exp -s); lunar samples can be used to study the history of solar activity. The uranium in the crystalline rocks occurs principally in small regions less than 10 to approximately equal to 100 micrometers in size. The (low) thermoluminescence of the fines increases with depth in core 10004. With one possible exception, x-ray studies have not shown pronounced radiation damage effects. The total energy release upon heating is small up to 900 C and occurs in three broad regions.

Crozaz, G.↗