In:
International Journal of Modern Physics E, World Scientific Pub Co Pte Ltd, Vol. 20, No. 06 ( 2011-06), p. 1491-1508
Abstract:
The unknown isotope 26 S , expected to decay by two-proton (2p) emission, was studied theoretically and searched experimentally. The structure of this nucleus was examined within the relativistic mean field (RMF) approach. A method for taking into account the many-body structure in the three-body decay calculations was developed. The results of the RMF calculations were used as an input for the three-cluster decay model optimized for the study of a possible 2p decay branch of this nucleus. The experimental search for 26 S was performed by fragmentation of a 50.3 A MeV 32 S beam. No events of a particle-stable 26 S or 25 P (a presumably proton-unstable subsystem of 26 S ) were observed. Based on the obtained production systematics, an upper half-life limit of T 1/2 〈 79 ns was established from the time-of-flight through the fragment separator. Together with the theoretical lifetime estimates for two-proton decay, this gives a decay energy limit of Q 2p 〉 640 keV for 26 S . Analogous limits for 25 P are found as T 1/2 〈 38 ns and Q p 〉 110 keV . In the case that the one-proton emission is the main branch of the 26 S decay, a limit Q 2p 〉 230 keV would follow for this nucleus. According to these limits, it is likely that 26 S resides in the picosecond lifetime range.
Type of Medium:
Online Resource
ISSN:
0218-3013
,
1793-6608
DOI:
10.1142/S0218301311018216
Language:
English
Publisher:
World Scientific Pub Co Pte Ltd
Publication Date:
2011
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