**ADOPTED LEVELS for ^{243}Fm**

__Authors:__ C.D. Nesaraja, E.A. Mccutchan **|** __Citation:__ Nucl. Data Sheets 121, 695 (2014) **|** __Cutoff date:__ 30-Sep-2013

Full ENSDF file | Adopted Levels (PDF version)

S(n)= 7107 keV SY | S(p)= 2726 keV SY | Q(α)= 8.69×10^{3} keV 5 | |||

Reference: 2012WA38 |

E(level) (keV) | J^{π}(level) | T_{1/2}(level) |

0.0 | (7/2-) | 231 ms 9 % α = 91 3 % SF = 9 1 % ε < 10 |

__Additional Level Data and Comments__:

E(level) | J^{π}(level) | T_{1/2}(level) | Comments |

1981Mu12: first identification using

^{206}Pb(^{40}Ar,3n) with E(^{40}Ar)=194 MeV. Assignment of 8546-MeV α activity to^{243}Fm was made based on the arguments that^{40}Ar bombarding energy was chosen to maximize for 3n channel, and that the observed α activity could not be assigned to any other nucleus.2008Kh10:

^{206}Pb(^{40}Ar,3n) with E(^{40}Ar)=180-204 MeV. Evaporation residues (Er) separated with the velocity filter SHIP and implanted into a position-sensitive Si detector. Fm isotopes identified through tof and Er-α and Er-SF correlations. Measured Eα, Iα, Er-α(t), Er-SF(t) using 7 position-sensitive Si detectors (implantation detector and 6 additional Si detectors mounted in the backward hemisphere); deduced T_{1/2}and branching. γ-rays measured with an HPGe clover detector; no isomers were identified.Theoretical calculations:

2013Zd01: T

_{1/2}for α decay calculated with phenomenological model based on Gamow theory with WKB approximation for Coulomb barrier penetration .2011Ad15: calculations for one-quasi particle states

2001Mo07: calculations of T

_{1/2}for α decay1985Cw01: fission barrier calculations

1984Ga06: calculations of fusion barrier for the (

^{206}Pb +^{40}Ar) system.1982Il01: calculations of

^{206}Pb(^{40}Ar,3n)^{243}Fm production cross sections1978Po09: calculations of spontaneous fission half-lives

1975Te01: T

_{1/2}(SF) estimated from data on fission activities following the^{206}Pb(^{40}Ar,xn) reaction and calculated excitation functions.1973Ta30: partial half-life for T

_{1/2}(ε decay) calculated from β gross theory.Q-value: ΔS(n)=455; ΔS(p)=334 (2012Wa38).

Q-value: S(2n)=15905 syst

368; S(2p)=4541 syst272; Q(εp)=2688 syst216(2012Wa38)