In-beam {gamma}-ray spectroscopy of neutron-rich boron isotopes {sup 15,17}B via inelastic scattering on {sup 12}C

Journal Article · Fri Apr 01 00:00:00 EST 2005 · Physical Review. C, Nuclear Physics

DOI:https://doi.org/10.1103/PhysRevC.71.044611· OSTI ID:20696083

Kondo, Y; Nakamura, T; Miura, M; Sugimoto, T ^[1]; Aoi, N; Fukuda, N; Gomi, T; Imai, N; Ishihara, M; Kubo, T; Motobayashi, T; Yanagisawa, Y ^[2]; Baba, H; Saito, A; Shimoura, S ^[3]; Bazin, D; Yoneda, K ^[4]; Hasegawa, H ^[5]; Kobayashi, T; Watanabe, K ^[6]

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1. Department of Physics, Tokyo Institute of Technology, 2-12-1 Oh-Okayama, Meguro, Tokyo 152-8551 (Japan)
2. Institute of Physical and Chemical Research (RIKEN), Hirosawa 2-1, Wako, Saitama 351-0198 (Japan)
3. Center for Nuclear Study (CNS), University of Tokyo, RIKEN campus, Hirosawa 2-1, Wako, Saitama 351-0198 (Japan)
4. National Superconducting Cyclotron Laboratory, Michigan State University, 1 Cyclotron, East Lansing, Michigan 48824-1321 (United States)
5. Department of Physics, Rikkyo University, Nishi-Ikebukuro 3-34-1, Toshima, Tokyo 171-8501 (Japan)
6. Department of Physics, Tohoku University, Katahira 2-1-1, Aoba, Sendai, Miyagi 980-8577 (Japan); and others

Low-lying bound states of the neutron-rich boron isotopes, {sup 15}B and {sup 17}B, have been investigated using the {sup 15,17}B+{sup 12}C inelastic scatterings at approximately 70 MeV/nucleon. In-beam {gamma}-ray spectroscopy was used to determine the energy levels of the excited states, and the angular distribution of the particle in the inelastic channel populating each state was measured. Two bound states were observed for {sup 15}B, while a new bound excited state was found for {sup 17}B at E{sub x}=1.07(1) MeV very close to the neutron emission threshold (S{sub 2n}=1.39 MeV). The angular distributions for the transitions to these states are well reproduced with {delta}L{sup {pi}}=2{sup +} diffraction patterns. The energy levels and {delta}L{sup {pi}}=2{sup +} are consistent with shell model predictions. The quadrupole deformation lengths for the transitions extracted from the differential cross sections are compared to the shell model, suggesting a strong quenching of the neutron effective charge both for {sup 15}B and {sup 17}B.

• OSTI ID: 20696083
• Journal Information: Physical Review. C, Nuclear Physics, Vol. 71, Issue 4; Other Information: DOI: 10.1103/PhysRevC.71.044611; (c) 2005 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA); ISSN 0556-2813
• Country of Publication: United States
• Language: English

Related Subjects

73 NUCLEAR PHYSICS AND RADIATION PHYSICS
ANGULAR DISTRIBUTION
BORON 15
BORON 17
BOUND STATE
CARBON 12
CARBON 12 TARGET
DEFORMED NUCLEI
DIFFERENTIAL CROSS SECTIONS
EFFECTIVE CHARGE
ENERGY-LEVEL TRANSITIONS
EXCITED STATES
GAMMA SPECTRA
GAMMA SPECTROSCOPY
HEAVY ION REACTIONS
INELASTIC SCATTERING
MEV RANGE
NEUTRON EMISSION
NEUTRONS
NUCLEAR DEFORMATION
PARITY
QUADRUPOLES
SHELL MODELS
SPIN