Published March 1977 | Version v1
Report Restricted

Observation of monoenergetic positrons in the decay of Eu152

Creators

Description

The positron spectrum of Eu152 has been measured with an iron-free high-transmission β-spectrometer of the orange type. The endpoint energies of the β+-spectra were newly determined (Wsub(o)122 = 729 +- 1.5 keV and Wsub(o)366 = 483 +- 6 keV). The multipolarity of the 1,408 keV transition in Sm152 was confirmed to be E1 by measuring the ratio αsub(ip)/αsub(K) = 0.39 +- 0.04. The relative intensity of the monoenergetic positron line of the same transition is Nsub(p)/Nsub(γ) = (9.3 +- 4.5) x 10-8. This value leads to a lifetime tau = (1.3 +- 0.6) x 10-14 sec for the 1,530 keV level in Sm152. Consequently the retardation factor for the 1,408 keV transition compared to the Weisskopf-estimate is R = 155. (orig.)

Availability note (English)

MF available from INIS under the Report Number.

Abstract (German)

Das Positronenspektrum von Eu152 wurde mit einem eisenfreien β-Spektrometer des Orangentyps gemessen. Das Geraet zeichnet sich durch besonders hohe Transmission aus. Dabei wurden die Endpunktsenergien der β+-Spektren mit einer besseren Genauigkeit als bisher bestimmt (Wsub(o)122 = 729 +- 1,5 keV und Wsub(o)366 = 483 +- 6 keV). Die Multipolaritaet des 1.408 keV Uebergangs in Sm152 wurde durch die Messung des Verhaeltnisses αsub(ip)/αsub(K) = 0,39 +- 0,04 als E1 bestaetigt. Die relative Intensitaet der monoenergetischen Positronenlinie desselben Uebergangs betraegt Nsub(p)Nsub(γ) = (9,3 +- 4,5) x 10-8. Fuer das 1.530 keV Niveau des Sm152 ergibt sich eine Lebensdauer von tau = (1,3 +- 0,6) x 10-14 sec. Der 1.408 keV Uebergang ist damit im Vergleich zur Weisskopf-Abschaetzung um einen Faktor R = 155 retardiert. (orig.)

Files

Restricted

The record is publicly accessible, but files are restricted to users with access.

Additional details

Additional titles

Original title (German)
Beobachtungen von monoenergetischen Positronen beim Zerfall des Kerns Eu

Publishing Information

Imprint Pagination
58 p.
Report number
KFK--2438

INIS

Country of Publication
Germany
Country of Input or Organization
Germany
INIS RN
8342564
Subject category
S73: NUCLEAR PHYSICS AND RADIATION PHYSICS;
Resource subtype / Literary indicator
Thesis
Descriptors DEI
BETA SPECTRA; BETA-PLUS DECAY; EUROPIUM 152; GAMMA RADIATION; LIFETIME; POSITRONS; SAMARIUM 152
Descriptors DEC
ANTILEPTONS; ANTIMATTER; ANTIPARTICLES; BASIC INTERACTIONS; BETA DECAY; BETA DECAY RADIOISOTOPES; BETA-MINUS DECAY RADIOISOTOPES; BETA-PLUS DECAY RADIOISOTOPES; DECAY; ELECTROMAGNETIC RADIATION; ELECTRON CAPTURE RADIOISOTOPES; ELEMENTARY PARTICLES; EUROPIUM ISOTOPES; EVEN-EVEN NUCLEI; FERMIONS; HOURS LIVING RADIOISOTOPES; INTERACTIONS; INTERMEDIATE MASS NUCLEI; IONIZING RADIATIONS; ISOTOPES; LEPTONIC DECAY; LEPTONS; MATTER; NUCLEI; ODD-ODD NUCLEI; PARTICLE DECAY; RADIATIONS; RADIOISOTOPES; RARE EARTH NUCLEI; SAMARIUM ISOTOPES; SPECTRA; STABLE ISOTOPES; WEAK INTERACTIONS; YEARS LIVING RADIOISOTOPES

Optional Information

Notes
32 figs.; 4 tabs.; 48 refs.