Authors: A.A. Sonzogni and B. Singh |  Citation: ENSDF |  Cutoff date: 23-Jun-2015 

 Full ENSDF file | Adopted Levels (PDF version) 

Q(β-)=1940 keV SYS(n)= 4590 keV SYS(p)= 7890 keV SYQ(α)= 3820 keV SY
Reference: 2012WA38

General Comments:

1960Di03: 241U measured indirectly through the detection of 241Pu (T1/2=14.29 y) and 241Am (T1/2=432.6 y) in the debris of the first large-scale thermonuclear test (Ivy Mike) of November 1, 1952 in the Pacific Ocean. Airborne and condensed samples were collected, followed by chemical extraction and purification. The isotopic composition of Pu, Am and Cm fractions were determined by using mass spectrometers, while the abundances of all the transcurium elements were measured by the detection of radiations, primarily α particles. Mass abundance of α=239-255 uranium isotopes at zero time were deduced which varies from 1.0 for 239U to 5.7×10-11 for 255U. The heavy uranium isotopes are expected to be produced in an environment of unusually high neutron flux (time-integrated flux of ≈1024 n/cm2) through successive neutron captures in 238U, with neutron energies of 14-MeV from deuterium-tritium fusion, and few MeV from the fission of 235U. The 241Am fraction can be formed in 241U --> 241Np --> 241Pu --> 241Am β- decay chain.

See also related articles: 1956Fi11, 1967Ho20, 1966Rg01 and 1969In01

2010To07: theoretical calculations of proton and neutron single-particle spectra, S(n), rms charge radius

Q-value: Estimated uncertainties (2012Wa38): 310 for Q(β-), 300 for S(n) and Q(α), 420 for S(p)

Q-value: S(2n)=10520 300, S(2p)=14990 500 (syst,2012Wa38)

  0? % β- = ?

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Additional Level Data and Comments:

  0 % β- = ?
β- is expected to be the dominant decay mode of 241U, since the theoretical half-life for α decay is >1020 s (1997Mo25).

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