Phys. Rev. Lett.
98,
212501
(2007)
[5 pages]
α Decay of 109I and Its Implications for the Proton Decay of 105Sb and the Astrophysical Rapid Proton-Capture Process
C. Mazzocchi1,2, R. Grzywacz1,3, S. N. Liddick4, K. P. Rykaczewski3, H. Schatz5, J. C. Batchelder4, C. R. Bingham1,3, C. J. Gross3, J. H. Hamilton6, J. K. Hwang6, S. Ilyushkin7, A. Korgul1,6,8,9, W. Królas9,10, K. Li6, R. D. Page11, D. Simpson1,12, and J. A. Winger4,7,9
1Department of Physics and Astronomy, University of Tennessee, Knoxville, Tennessee 37996, USA 2IFGA, University of Milan and INFN, Milano, I-20133, Italy 3Physics Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA 4UNIRIB, Oak Ridge Associated Universities, Oak Ridge, Tennessee 37831, USA 5National Superconducting Cyclotron Laboratory, Michigan State University, East Lansing, Michigan 48824, USA 6Department of Physics and Astronomy, Vanderbilt University, Nashville, Tennessee 37235, USA 7Department of Physics and Astronomy, Mississippi State University, Mississippi 39762, USA 8Institute of Experimental Physics, Warsaw University, Warszawa, PL 00-681, Poland 9Joint Institute for Heavy-Ion Reactions, Oak Ridge, Tennessee 37831, USA 10Institute of Nuclear Physics, Polish Academy of Sciences, PL 31-342 Kraków, Poland 11Department of Physics, University of Liverpool, Liverpool, L69 7ZE, United Kingdom 12Department of Physics, Astronomy, and Geology, East Tennessee State University, Johnson City, Tennessee 37614, USA
Received 7 March 2007; published 23 May 2007
An α-decay branch of (1.4±0.4)×10-4 has been discovered in the decay of 109I, which predominantly decays via proton emission. The measured Qα value of 3918±21 keV allows the indirect determination of the Q value for proton emission from 105Sb of 356±22 keV, which is approximately of 130 keV more bound than previously reported. This result is relevant for the astrophysical rapid proton-capture process, which would terminate in the 105Sn(p,γ)106Sb(p,γ)107Te(α decay)103Sn cycle at the densities expected in explosive hydrogen burning scenarios, unless unusually strong pairing effects result in a 103Sn(p,γ)104Sb(p,γ)105Te(α decay)101Sn) cycle.
© 2007 The American Physical Society
URL:
http://link.aps.org/doi/10.1103/PhysRevLett.98.212501
DOI:
10.1103/PhysRevLett.98.212501
PACS:
23.60.+e, 21.10.Dr, 23.50.+z, 27.60.+j
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