A Theory of Hyperfragments (open access)

A Theory of Hyperfragments

"Mesic decay of hyperfragments is discussed systematically on the basis of a previous model for hyperfragments. The general formalism for the two-body and three-body mesic decay was developed. The polarization-direction correlation and the angular correlation for the two-body and the three-body decays are discussed together with the decay probability. The formalism was developed so as to include the isotopic spin selection rule ( DELTA I = 1/2 and 3/2) for the mesic decays. The theory was applied especially for the low mass number hypergragments where it was found that the branching ratios of the two-body and the three-body mesic decays of /sup 3/H/sub i and /sup 4/H/sub i, (/sup 3/ H/sub i yields /sup 3/He + i/sup -/)/(/sup 3/H/sub i yields D + p+ pi /sup -/) and (/sup 4/H/sub i yields /sup 4/He + pi /sup -/)/(/sup 4/H/ sub i yields /sup 3/H + p + pi /sup -/), could be used for the determination of the spins of both hyperfragments. The fraction of the p-wave decay rate for the free LAMBDA decay obtained from the reaction /sup 5/He/sub i yields /sup 4/He + p + pi where the decay proceeds through two-resonant states (p/sub 3/2/ and p/sub 1/2/) …
Date: February 28, 1961
Creator: Iwao, Syurei
System: The UNT Digital Library
Fission Product Activity in SM-1 Core I Primary System and Surface Contamination on SM-1 Type Fuel Elements. Task XVIII, Phases 2 and 3 (open access)

Fission Product Activity in SM-1 Core I Primary System and Surface Contamination on SM-1 Type Fuel Elements. Task XVIII, Phases 2 and 3

Abstract; The fission product data obtained during SM-1 Core I operation (June 1957 - May 1960) is reviewed briefly and interpreted. Evidence is presented to indicate that a fuel element defect was responsible for the high fission product activity level observed in the primary coolant. Relative escape coefficients are calculated and the defect size estimated. Anticipated fission product levels during SM-1 Core II and SM-1A Core I operation are estimated from alpha surface contamination data on completed fuel elements. The importance of in-line sampling for monitoring fission product activity is stressed as well as the need for failed fuel element detection methods.
Date: February 28, 1961
Creator: Hasse, Robert A. & Zegger, John L.
System: The UNT Digital Library
Improved Zirconium Alloys : Summary Report, April 1, 1960 - January 31, 1961 (open access)

Improved Zirconium Alloys : Summary Report, April 1, 1960 - January 31, 1961

Abstract: "The objectives of this program are the development of zirconium-base alloys possessing exceptionally good corrosion resistance to 680 F water or 750-900 F system and/or improved strength at elevated temperatures. Approximately 100 binary compositions were prepared and screened by corrosion testing in 680 F water; selected compositions were exposed to 750 F steam. The data obtained indicate promising bases for ternary and quaternary alloys. Related investigations involving zirconium purity and heat treatment for improvement of corrosion properties are proceeding. Hydrogen pickup and mechanical properties will be used as acceptability tests on promising compositions."
Date: February 28, 1961
Creator: Weinstein, Daniel; Holtz, F. C. & Van Thyne, R. J.
System: The UNT Digital Library