Detailed spectroscopy of {sup 249}Fm

Journal Article · Sun Oct 15 04:00:00 EDT 2006 · Physical Review. C, Nuclear Physics

DOI:https://doi.org/10.1103/PHYSREVC.74.044303· OSTI ID:20863846

Lopez-Martens, A; Hauschild, K; Briancon, Ch; Korichi, A ^[1]; Yeremin, A V; Belozerov, A V; Chelnokov, M L; Chepigin, V I; Gorshkov, V A; Kabachenko, A P; Malyshev, O N; Oganessian, Yu Ts; Popeko, A G; Sagaidak, R N; Shutov, A V; Svirikhin, A I ^[2]; Curien, D; Dorvaux, O; Gall, B; Khalfallah, F ^[3]

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1. CSNSM, IN2P3-CNRS, F-91405 Orsay Campus (France)
2. FLNR, JINR, Dubna (Russian Federation)
3. IPHC, IN2P3-CNRS, F-67037 Strasbourg (France)

Excited states in {sup 249}Fm were populated via the {alpha} decay of {sup 253}No and the subsequent decay was observed with the GABRIELA detection system installed at the focal plane of the VASSILISSA recoil separator. The energies, spins, and parities of these states could be established through combined {alpha},{gamma}, and conversion-electron spectroscopy. The first members of the ground-state rotational band were identified. Their excitation energies as well as the observation of a cross-over E2 transition confirm the assignment of 7/2{sup +}624 for the ground state of {sup 249}Fm. Two excited states were also observed and their decay properties suggest that they correspond to the particle excitation 9/2{sup -}734 and hole excitation 5/2{sup +}622. The analysis suggests that the 279-keV transition de-exciting the 9/2{sup -} state has anomalous E1 conversion coefficients.

• OSTI ID: 20863846
• Journal Information: Physical Review. C, Nuclear Physics, Journal Name: Physical Review. C, Nuclear Physics Journal Issue: 4 Vol. 74; ISSN 0556-2813; ISSN PRVCAN
• Country of Publication: United States
• Language: English

Related Subjects

73 NUCLEAR PHYSICS AND RADIATION PHYSICS
ALPHA DECAY
CONVERSION
E2-TRANSITIONS
ELECTRON SPECTROSCOPY
EXCITATION
FERMIUM 249
GROUND STATES
KEV RANGE
NOBELIUM 253
PARITY
PARTICLE-HOLE MODEL
RECOILS
ROTATIONAL STATES
SPIN