https://doi.org/10.1140/epja/i2011-11064-9
Regular Article - Experimental Physics
Improved characteristics of the 22.5 keV (M1 + E2) nuclear transition in 149Sm
1
Laboratory of Nuclear Problems, JINR, Dubna, Moscow Region, Russian Federation
2
Institute of Applied Physics, National University, Tashkent, Republic of Uzbekistan
3
Nuclear Physics Institute of the ASCR, Řež near Prague, Czech Republic
* e-mail: inoyatov@nusun.jinr.ru
Received:
2
February
2011
Revised:
4
April
2011
Accepted:
19
April
2011
Published online:
25
May
2011
The gamma ray and conversion electron spectra of the 22.5keV M1 + E2 nuclear transition depopulating the first excited level 5/2− in 149Sm were investigated in detail. A substantially improved value of 22500.2 ± 0.8 eV for the transition energy was determined that opens a possibility to establish an electron energy standard for the keV region based on the conversion electron lines of this transition. The E2 admixture parameter |δ(E2/M1)| = 0.0784 ± 0.0009 and the nuclear structure parameter λ = − 2 ± 10 were derived. The |δ(E2/M1)| and λ parameters were also obtained for all available experimental data and their mutual combination.
© SIF, Springer-Verlag Berlin Heidelberg, 2011