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arXiv · 1010.6250

The half-life of $^{221}$Fr in Si and Au at 4K and at mK temperatures

F. Wauters·B. Verstichel·M. Breitenfeldt·V. De Leebeeck·V. Yu. Kozlov·I. Kraev·S. Roccia·G. Soti·M. Tandecki·E. Traykov·S. Van Gorp·D. Z'akouck'y·N. Severijns
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Abstract

The half-life of the $\alpha$ decaying nucleus $^{221}$Fr was determined in different environments, i.e. embedded in Si at 4 K, and embedded in Au at 4 K and about 20 mK. No differences in half-life for these different conditions were observed within 0.1%. Furthermore, we quote a new value for the absolute half-life of $^{221}$Fr of t$_{1/2}$ = 286.1(10) s, which is of comparable precision to the most precise value available in literature.

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F. Wauters, B. Verstichel, M. Breitenfeldt, V. De Leebeeck, V. Yu. Kozlov, I. Kraev, S. Roccia, G. Soti, M. Tandecki, E. Traykov, S. Van Gorp, D. Z'akouck'y, N. Severijns. 2010-10-29. The half-life of $^{221}$Fr in Si and Au at 4K and at mK temperatures. https://doi.org/10.1103/physrevc.82.064317

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