M. Serata

Isomeric 0+ state in 12Be

An isomeric 0+ state at E x = 2.24 MeV in 12Be was found in the projectile fragmentation of 18O at 100 A MeV on a Be target. The excitation energy and the spin assignment were deduced by the measurements of the energies and the angular correlation function of the coincident two γ-rays corresponding to the 0+ → 2+ → 0+ decay, respectively.

Isobaric analog state of 14Be

The halo structure of the neutron-dripline nucleus 14Be has been investigated by various approaches, such as the interaction cross section measurement, dissociation reaction and 14Be fragmentation. In the recent plausible view, the mixing of s and d-wave components in the halo wave function has been suggested. In the present study, the halo structure of 14Be was investigated by measuring its Isobaric Analog State (IAS). Since the wave function of the IAS is essentially the same as that of its isobaric partner, possible exotic natures of 14Be may be traced in properties of the IAS such as the Coulomb displacement energy (ΔE C) and the width of the IAS. The IAS of the 14Be was excited by the charge-exchange reaction which was successfully applied to the neutron-dripline nucleus 11Li and obtained the halo properties [1, 2]. In the present study, applying this reaction to 14Be, we have measured the 14Be(p,n)14B* reaction in inverse kinematics at E in = 74 A MeV [3].

Molecular states in neutron-rich beryllium isotopes

Excited states in 1 2 Be and 1 4 Be were studied by using an exotic beam of 1 4 Be at 75 A MeV. A new excited state in 1 2 Be was observed at 11.8 MeV. The angular-correlation analysis showed that the spin for the new level is tentatively assigned to be 0. According to the energy-spin systematics, the observed state may be a member of the rotational band of the 6 He- 6 He cluster structure. Three excited states in 1 4 Be were also found at 10.8 MeV, 11.6 MeV, and 15.5 MeV.

Inelastic Scattering of 12Be with 4He

. Inelastic scattering of the neutron-rich nucleus 1 2 Be on a liquid-He target has been studied by measuring de-excitation γ rays in coincidence with scattered 1 2 Be. In the angular distribution, a difference between the 2 + 1 and the 1- state in 1 2 Be was cleary seen.

Coulomb Excitation of 24Si

We have measured Coulomb excitation of 2 4 Si to its first excited state to obtain the E2 transition probability. This is the first measurement of B(E2) for a T z = -2 nucleus, which enables us to compare their transitionprobabilities between the mirror pair of T = 2, namely 2 4 Si and 2 4 Ne.

Exotic cluster states in 12Be via α‐inelastic scattering

Excited states in the neutron‐rich nucleus 12Be were experimentally investigated via α‐inelastic scattering. The excited states in the 12Be nucleus were populated by a 12Be(α,α′) reaction at 60 A MeV in the inverse kinematics, and identified by measuring a 6He+6He breakup channel in coincidence. The differential cross section and the angular correlations between the decay particles were obtained for each excitation energy from 10 MeV to 20 MeV, reconstructed by the measured momentum vectors of the two 6He’s.A multipole decomposition analysis based on the distorted‐wave Born approximation was applied for the angular distribution of the inelastic scattering together with the angular correlation between the decay particles with respect to the directions of the incident beam and to the momentum transfer simultaneously. From the decomposed excitation energy spectra for L=0, 2, and 4, new excited states with Jπ=0+ and Jπ=2+ were identified, which were candidates of the band‐head of a largely deformed rotational...

Coulomb dissociation experiment for explosive hydrogen burning: Study of the 22Mg(p, γ)23Al reaction

By taking advantage of the high efficiency of the Coulomb dissociation method, we studied the stellar 22Mg(p, γ)23Al reaction. The radiative width Γγ of the first excited state in 23Al was determined by measuring the intermediate-energy 23Al → 22Mg + p breakup process with a lead target.

Investigation of Stellar 26Si(p,γ)27P Reaction via Coulomb Dissociation

The Coulomb dissociation of the proton-rich nuclei {sup 27}P was studied experimentally using {sup 27}P beams at 57 MeV/nucleon with a lead target. The radiative widths of the low-lying excited state in {sup 27}P were deduced. The resonant capture reaction rate of stellar {sup 26}Si(p,{gamma}){sup 27}P through these states was estimated using the measured radiative widths. The astrophysical implications obtained from the extracted reaction rate will be discussed.

Investigation of Stellar 26 Si (p,γ) 27 P Reaction via Coulomb Dissociation

The Coulomb dissociation of the proton-rich nuclei {sup 27}P was studied experimentally using {sup 27}P beams at 57 MeV/nucleon with a lead target. The radiative widths of the low-lying excited state in {sup 27}P were deduced. The resonant capture reaction rate of stellar {sup 26}Si(p,{gamma}){sup 27}P through these states was estimated using the measured radiative widths. The astrophysical implications obtained from the extracted reaction rate will be discussed.

Coulomb Dissociation of 27P for Study of 26Si(p,γ)27P Reaction

The Coulomb dissociation of the proton‐rich nuclei 27P was studied experimentally using a 27P beam at 57 MeV/nucleon with a lead target. The γ decay widths of the low‐lying excited states in 27P were deduced. The resonant capture reaction rate of stellar 26Si(p,γ)27P through these states was estimated using the measured γ decay width. The astrophysical implications derived from the estimated reaction rate is discussed.