DISCUSSION ON THE LOWEST ENERGY POSITRON DECAY

Authors
Citation
M. Skalsey, DISCUSSION ON THE LOWEST ENERGY POSITRON DECAY, Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment, 408(2-3), 1998, pp. 486-490
Citations number
20
Categorie Soggetti
Nuclear Sciences & Tecnology","Physics, Particles & Fields","Instument & Instrumentation",Spectroscopy
ISSN journal
01689002
Volume
408
Issue
2-3
Year of publication
1998
Pages
486 - 490
Database
ISI
SICI code
0168-9002(1998)408:2-3<486:DOTLEP>2.0.ZU;2-Y
Abstract
Positrons (e(+)) from Ni-59 decay have a maximum energy of 51 keV, the lowest known energy for a e(+) transition. The identifying signal is e(+)e(-) annihilation into two 511 keV gamma-rays that can be readily observed. Modern Ge detector arrays offer the opportunity to accuratel y check the Ni-59 result (to resolve an apparent error in the intensit y) and, further, to search for even lower energy e(+) decays. The extr emely small e(+) branching ratios associated with such decays: (1) req uire efficient detection and suppression of backgrounds and (2) limit the practical utility of low energy e(+) transitions. Branching ratio results for allowed low energy e(+) decays could be compared to atomic theory calculations and, at high precision, test weak interaction the ory. (C) 1998 Elsevier Science B.V. All rights reserved.