ADOPTED LEVELS for 241U
Authors: Balraj Singh and A.A. Sonzogni | Citation: ENSDF | Cutoff date: 12-Apr-2023
Authors: A.A. Sonzogni and B. Singh | Citation: ENSDF | Cutoff date: 23-Jun-2015
Full ENSDF file | Adopted Levels (PDF version)
| Q(β-)=1830 keV 55 | S(n)= 4605 keV 45 | S(p)= 8120 keV SY | Q(α)= 3802 keV 48 | ||
| Reference: 2023NI04,2021WA16 |
| E(level) (keV) | T1/2(level) |
| 0 | % β- = 100 |
Additional Level Data and Comments:
| E(level) | Jπ(level) | T1/2(level) | Comments |
| 0 | % β- = 100 | β- is expected to be the dominant decay mode of 241U, since the theoretical half-life for α decay is >1020 s (2019Mo01), thus 100% β- decay is assigned by inference (evaluators). E(level): β- is expected to be the dominant decay mode of 241U, since the theoretical half-life for α decay is >1020 s (2019Mo01), thus 100% β- decay is assigned by inference (evaluators). |
2023Ni04: 241U isotope was produced in multinucleon transfer (MNT) reaction 198Pt(238U,X),E(238U)=10.75 MeV/nucleon, followed by ionization and identification in mass and charge of projectile-like fragments using two-color, two-step laser ionization technique with an appropriate choice of tunable wavelength. The separated ions were stopped in windowless gas cell-based ion cooler buncher (GCCB), and finally injected into the multireflection time-of-flight mass spectrograph (MRTOF-ms) for precise mass determination at the KEK Isotope Separation System (KISS) at RIKEN Ring cyclotron facility. 133Cs ions were used as reference for mass measurements.
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.
Theoretical calculations:
2017Ro28: calculated binding energy, rotational energy, octupole and hexadecapole moments versus quadrupole moment, fission T1/2 within HFB-EFA (HFB Equal Filling Approximation) using Gogny D1M EDF.
2016Pa06: calculated T1/2(β-) using FFST (Finite Fermi Systems Theory) with masses from FRDM or ETFSI.
2010To07: calculated proton and neutron single-particle spectra, S(n), rms charge radius
Q-value: Q(β-) from measured mass excesses of 56182 keV 45 for 241U and 54352 keV 31 for 241Np (2023Ni04). Other: 1880 220 (syst, 2021Wa16).
Q-value: S(n) from measured mass excesses of 56182 keV 45 for 241U (2023Ni04) and 52715.5 keV 26 for 240U (2021Wa16). Other: 4590 200 (syst, 2021Wa16).
Q-value: S(p)=8120 205 (syst) from measured mass excesses of 56182 keV 45 for 241U (2023Ni04) and 57010 keV 200 for 240Pa (syst, 2021Wa16). Other: 8100 280 (syst, 2021Wa16).
Q-value: Q(α) from measured mass excesses of 56182 keV 45 for 241U (2023Ni04) and 49955 keV 16 for 237Th (2021Wa16). Other: 3820 200 (syst, 2021Wa16).
Q-value: S(2n)=10533 45 from measured mass excesses of 56182 keV 45 for 241U (2023Ni04) and 50572.7 keV 15 for 239U (2021Wa16). Other: 10520 200 (syst, 2021Wa16).
Q-value: S(2p)=14900 400 (syst) from measured mass excesses of 56182 keV 45 for 241U (2023Ni04) and 56500 keV 400 for 239Th (syst, 2021Wa16). Other: 14880 450 (syst, 2021Wa16).