Large proton contribution to the 2{sup +} excitation in {sup 20}Mg studied by intermediate energy inelastic scattering

Journal Article · Fri Aug 15 00:00:00 EDT 2008 · Physical Review. C, Nuclear Physics

DOI:https://doi.org/10.1103/PHYSREVC.78.024306· OSTI ID:21192104

Iwasa, N ^[1]; Motobayashi, T; Bishop, S; Kurokawa, M; Minemura, T; Sakurai, H; Yamada, K; Yanagisawa, Y ^[2]; Elekes, Z ^[2]; Gibelin, J ^[3]; Hosoi, M; Sugawara, K; Suzuki, T ^[4]; Ieki, K; Kawai, S; Kurita, K; Morikawa, H; Takeshita, E; Togano, Y; Yamaguchi, K ^[3]

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1. Department of Physics, Tohoku University, Sendai, Miyagi 980-8578 (Japan)
2. RIKEN - Institute of Physical and Chemical Research, Wako, Saitama 351-0198 (Japan)
3. Department of Physics, Rikkyo University, Toshima, Tokyo 171-8501 (Japan)
4. Department of Physics, Saitama University, Shimo-Ohkubo, Saitama 338-8570 (Japan)

Coulomb excitation of the proton-rich nucleus {sup 20}Mg was studied using a radioactive {sup 20}Mg beam at 58A MeV impinging on a lead target. The reduced transition probability B(E2;0{sub g.s.}{sup +}{yields}2{sub 1}{sup +}) was extracted to be 177(32) e{sup 2} fm{sup 4}, which agrees with the theoretical predictions by a cluster model assuming {sup 16}O + 2p + 2p structure, a mean-field approach based on the angular momentum projected generator coordinate method, and the USD shell model. The ratio of the neutron-to-proton multipole matrix elements M{sub n}/M{sub p} in the mirror nucleus {sup 20}O was deduced to be 2.51(25) with the M{sub n} value evaluated from the measured B(E2) value for {sup 20}Mg with the help of isospin symmetry. The results confirm the large M{sub n}/M{sub p} value previously reported in {sup 20}O, leading to the dominant role of the four valence nucleons in the 2{sub 1}{sup +} excitation and persistence of the {sup 16}O core in {sup 20}O and {sup 20}Mg.

• OSTI ID: 21192104
• Journal Information: Physical Review. C, Nuclear Physics, Vol. 78, Issue 2; Other Information: DOI: 10.1103/PhysRevC.78.024306; (c) 2008 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 MOMENTUM
BEAMS
CLUSTER MODEL
COULOMB EXCITATION
GENERATOR-COORDINATE METHOD
INELASTIC SCATTERING
ISOSPIN
MAGNESIUM 20
MATRIX ELEMENTS
MEAN-FIELD THEORY
MEV RANGE 10-100
MIRROR NUCLEI
NEUTRON-DEFICIENT ISOTOPES
NEUTRONS
OXYGEN 16
OXYGEN 20
PROBABILITY
PROTONS
SHELL MODELS
SYMMETRY