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DOE OSTI · 3003137

Core-excited microsecond isomer in 207 Pb

Tandel, S. K. [Shiv Nadar Institution of Eminence, Delhi-NCR (India); University of Massachusetts, Lowell, MA (United States)] (ORCID:0000000347843139)·Wahid, S. G. [University of Massachusetts, Lowell, MA (United States)] (ORCID:0000000257308028)·Krishnadev, N. [Instituto Biofisika (Spain)] (ORCID:0000000177053213)·Hemalatha, M. [University of Mumbai (India)]·Sahoo, Subhrajit [Indian Institute of Technology Roorkee (India)] (ORCID:0000000180002150)·Srivastava, P. C. [Indian Institute of Technology Roorkee (India)] (ORCID:0000000187191548)·Chowdhury, P. [University of Massachusetts, Lowell, MA (United States)]·Janssens, R. V. F. [University of North Carolina at Chapel Hill, NC (United States); Duke University, Durham, NC (United States)] (ORCID:0000000170951715)·Kondev, F. G. [Argonne National Laboratory (ANL), Argonne, IL (United States)] (ORCID:0000000295675785)·Carpenter, M. P. [Argonne National Laboratory (ANL), Argonne, IL (United States)]·Lauritsen, T. [Argonne National Laboratory (ANL), Argonne, IL (United States)]·Seweryniak, D. [Argonne National Laboratory (ANL), Argonne, IL (United States)]
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Abstract

An isomeric state with T 1/2 = 1.46(10) μs and E x = 8835 keV has been established in 207 Pb. Here, this state likely arises from the occupation of neutron holes in the high-j i 13/2 and j 15/2 subshells following the excitation of the 208 Pb core. The high-spin excited level structure of 207 Pb has been extended beyond the previously known states up to E x ≈ 6 MeV. Additionally, a more precise value of the half-life of the I π = 10 + isomer in 208 Pb has been obtained. Shell-model calculations provide a good account of the structure up to the 31/2 + level in 207 Pb, while the energies of higher-spin states built from exclusively high-j nucleons are considerably underestimated.

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190 ≤ A ≤ 219High spin statesIsomer decaysNuclear structure & decayshigh spin statesisomer decaysnuclear structure & decays

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Tandel, S. K. [Shiv Nadar Institution of Eminence, Delhi-NCR (India); University of Massachusetts, Lowell, MA (United States)] (ORCID:0000000347843139), Wahid, S. G. [University of Massachusetts, Lowell, MA (United States)] (ORCID:0000000257308028), Krishnadev, N. [Instituto Biofisika (Spain)] (ORCID:0000000177053213), Hemalatha, M. [University of Mumbai (India)], Sahoo, Subhrajit [Indian Institute of Technology Roorkee (India)] (ORCID:0000000180002150), Srivastava, P. C. [Indian Institute of Technology Roorkee (India)] (ORCID:0000000187191548), Chowdhury, P. [University of Massachusetts, Lowell, MA (United States)], Janssens, R. V. F. [University of North Carolina at Chapel Hill, NC (United States); Duke University, Durham, NC (United States)] (ORCID:0000000170951715), Kondev, F. G. [Argonne National Laboratory (ANL), Argonne, IL (United States)] (ORCID:0000000295675785), Carpenter, M. P. [Argonne National Laboratory (ANL), Argonne, IL (United States)], Lauritsen, T. [Argonne National Laboratory (ANL), Argonne, IL (United States)], Seweryniak, D. [Argonne National Laboratory (ANL), Argonne, IL (United States)]. 2025-08-01. Core-excited microsecond isomer in 207 Pb. https://doi.org/10.1103/6l8p-cblc

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