English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

The first ever search for $\alpha$ decays to the first excited state in Ybwas performed for six isotopes of hafnium (174, 176, 177, 178, 179, 180) usinga high purity Hf-sample of natural isotopic abundance with a mass of 179.8 g.For $^{179}$Hf, also $\alpha$ decay to the ground state of $^{175}$Yb wassearched for thanks to the $\beta$-instability of the daughter nuclide$^{175}$Yb. The measurements were conducted using an ultra low-backgroundHPGe-detector system located 225 m underground. After 75 d of data taking nodecays were detected but lower bounds for the half-lives of the decays werederived on the level of $\lim T_{1/2}\sim 10^{15}-10^{18}$~a. The decay withthe shortest half-life based on theoretical calculation is the decay of$^{174}$Hf to the first $2^+$ 84.3~keV excited level of $^{170}$Yb. Theexperimental lower bound was found to be $T_{1/2}\geq 3.3\times 10^{15}$ a.

First search for $\alpha$ decays of naturally occurring Hf nuclides with emission of $\gamma$ quanta