Die β-Zerfallsenergie der Technetiumisotope Tc¹⁰³, Tc¹⁰⁴ und Tc¹⁰⁵

Abstract

Molybdenum fission products from Uranium were rapidly separated using a sublimation technique. Their Technetium daughters could be separated from the Molybdenum sample by a second sublimation. The decay of Tc¹⁰³, Tc¹⁰⁴ and Tc¹⁰⁵ was investigated using scintillation counters and coincidence methods.

Tc¹⁰³ decays by the emission of twoβ-groups at energies of 2·0 Mev and 2·2 Mev followed byγ-lines of 135 kev, 215 kev and 350 kev. According to a proposed decay-scheme Tc¹⁰³ decays with aQ-value of 2·35±0·10 Mev into Ru¹⁰³.

Tc¹⁰⁵ emits aβ-group of about 3·4 Mev maximum energy followed by a 110 kevγ-transition. TheQ-value of the Tc¹⁰⁵ decay was estimated to be 3·4±0·2 Mev. Fromβ−γ- andγ−γ-coincidence spectra of Tc¹⁰⁴ fourβ−γ-γ-cascades could be identified, which populate excited states of 0·36 Mev, 0·89 Mev, 2·5 Mev, 3·5 Mev and 4·05 Mev in Ru¹⁰⁴. TheQ-value of the Tc¹⁰⁴ decay was found to be 5·85±0·10 Mev.

TheQ-values and spin assignements of the groundstates of Tc¹⁰³ and Tc¹⁰⁵ are discussed in a more detailedβ-decay systematic.