Abstract
The fusion reaction74Se+106Cd→180Pb* at a compound nucleus excitation energy Ex ≃ 40 MeV, has been used in a search for the decay of the unknown nucleus177Tl. Evaporation residues were velocity and mass analysed prior to implantation into a position sensitive silicon surface barrier detector. No evidence was discovered for the proton or alpha-decay of177Tl for a cross-section > 10 5+10− nb. This indicates either that177Tl decays too rapidly (t1/2 < 1 μs) by proton emission for the decay to be detected, or that177Tl is produced with a cross-section less than the limit established in the present experiment. The following nuclear decay half-lives were measured with improved accuracy;177Hg (t1/2 = 130±5 ms),178Hg (t1/2=250±25 ms) and177Au (t1/2=1180±70 ms). The experiment also provided the first direct confirmation of the correct mass assignment of the alpha-decay, Eα=6.26 MeV, to the decay of176Au. Two additional halflife measurements of proton-rich Osmium isotopes are also presented from a previous similar experiment;165Os (t1/2=73±8 ms) and166Os (t1/2 = 194±17 ms).
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Sellin, P.J., Woods, P.J., Page, R.D. et al. The limit of stability of proton-rich thallium isotopes: a search for the decay of177Tl. Z. Physik A - Hadrons and Nuclei 338, 245–246 (1991). https://doi.org/10.1007/BF01284803
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DOI: https://doi.org/10.1007/BF01284803