List of levels for 240CF

Author: C. Morse | Citation: Nucl. Data Sheets 206, 359 (2025) | Cutoff date: 27-Sep-2024

$ 1970Si19: ²⁴⁰Cf produced by bombardment of ^233-235U with ¹²C ions at ORNL. Measured E_α, T_1/2.

$ 1995La09: ²⁴⁰Cf produced at Dubna by ²⁰⁸Pb(³⁴S,2n) and ²⁰⁶Pb(³⁶S,2n) reactions with an incident beam energy of 215 MeV. Measured T_1/2, %SF.

$ 2010Kh06: ²⁴⁰Cf activity produced in reactions ²⁰⁶Pb(³⁶S,2n) E=163.6, 172.6 MeV and ²⁰⁷Pb(³⁶S,3n) E=165.5, 170.3 MeV. PbS targets with isotopic enrichment of >99% were used. Evaporation residues (ERs) were separated from the primary beam and target-like ions by the velocity filter SHIP and ERs detected by a position-sensitive 16 strip Si detector. Measured E_α, time-distribution of α-decays, T_1/2, decay modes.

Q-value: ΔQ(β^-)=366, ΔS(n)=121, ΔS(p)=208 (2021Wa16)

Q-value: S(2n)=15431 syst 299, S(2p)=6034 22 (2021Wa16)

Q(β-)=-6237 keV SY	S(n)= 8284 keV SY	S(p)= 3550 keV SY	Q(α)= 7711 keV 4
Reference: 2021Wa16

E(level) (keV)	J^π(level)	T_1/2(level)
0	0+	1.00 m 12 % α = 98.5 2 % ε = ? % SF = 1.5 2

E(level)	J^π(level)	T_1/2(level)	Comments
0	0+	1.00 m 12 % α = 98.5 2 % ε = ? % SF = 1.5 2	Only the α decay and SF decay modes have been observed. Calculations of 2019Mo01 predict T_1/2=78.6 s for β decay and T_1/2=776 s for α decay, suggesting that a significant fraction of the decay proceeds by β decay. However gross theory calculations of 1973Ta30 predict 400-10⁶ s which suggests <14% ε+β⁺ decay. 2010Kh06 claim electron-capture decay is negligible, citing 1996FiZX. E(level): Only the α decay and SF decay modes have been observed. Calculations of 2019Mo01 predict T_1/2=78.6 s for β decay and T_1/2=776 s for α decay, suggesting that a significant fraction of the decay proceeds by β decay. However gross theory calculations of 1973Ta30 predict 400-10⁶ s which suggests <14% ε+β⁺ decay. 2010Kh06 claim electron-capture decay is negligible, citing 1996FiZX.