Eur. Phys. J. A (2016) 52: 133
https://doi.org/10.1140/epja/i2016-16133-y

Regular Article - Experimental Physics

Improved energy of the 21.5 keV M1 + E2 nuclear transition in ¹⁵¹Eu

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, CZ-25068, Řež near Prague, Czech Republic
⁴ Institute of Nuclear Physics, Ibragimov St. 1, 050032, Almaty, Kazakhstan

^* e-mail: inoyatov@jinr.ru

Received: 30 November 2015
Revised: 1 April 2016
Accepted: 5 April 2016
Published online: 17 May 2016

Abstract

Using internal conversion electron spectroscopy, improved energy 21 541.5±0.5 eV was determined for the 21.5keV M1 + E2 nuclear transition in ¹⁵¹Eu populated in the electron capture decay of ¹⁵¹Gd . This value was found to agree well with the present adopted value but is much more accurate. A value of 0.0305±0.0011 derived for the E2 admixture parameter from the measured conversion electron line intensities corresponds to the present adopted value. A possible effect of nuclear structure on the multipolarity of the 21.5 keV transition was also investigated.