402 research outputs found
Five-body resonances of 8C using the complex scaling method
We study the resonance spectroscopy of the proton-rich nucleus 8C in the
alpha+p+p+p+p cluster model. Many-body resonances are treated on the correct
boundary condition as the Gamow states using the complex scaling method. We
obtain the ground state of 8C as a five-body resonance for the first time,
which has dominantly the sub-closed (p_{3/2})^4 configuration and agrees with
the recent experiment for energy and decay width. We predict the second 0+
state with the excitation energy of 5.6 MeV, which corresponds to the
state from the ground state. We evaluate the occupation numbers of four
valence-protons in the 8C states and also the J^\pi distribution of proton-pair
numbers of the two 0+ states of 8C. The ground state involves a large amount of
the 2+ proton-pair fraction, while the excited 0+_2 state almost consists of
two of the 0+ proton pairs, which can be understood from the
(p_{3/2})^2(p_{1/2})^2 configuration. We also discuss the mirror symmetry
between 8C and 8He with an alpha+four nucleon picture. It is found that the 0+
states retain the mirror symmetry well for the configuration properties of two
nuclei.Comment: 8 pages, 6 figures. arXiv admin note: text overlap with
arXiv:1111.5070, radial properties of 8C are revised in Table II
Coulomb breakup reactions of Li in the coupled-channel Li~+~~+~ three-body model
We investigate the three-body Coulomb breakup of a two-neutron halo nucleus
Li. We use the coupled-channel Li + + three-body model,
which includes the coupling between last neutron states and the various
- configurations in Li due to the tensor and pairing correlations.
The three-body scattering states of Li are described by using the
combined methods of the complex scaling and the Lippmann-Schwinger equation.
The calculated breakup cross section successfully reproduces the experiments.
The large mixing of the s-state in the halo ground state of Li is shown
to play an important role in explanation of shape and strength of the breakup
cross section. In addition, we predict the invariant mass spectra for binary
subsystems of Li. It is found that the two kinds of virtual s-states of
Li- and - systems in the final three-body states of Li
largely contribute to make low-lying peaks in the invariant mass spectra. On
the other hand, in the present analysis, it is suggested that the contributions
of the p-wave resonances of Li is hardly confirmed in the spectra.Comment: 26 pages, 11 figures, 2 tables, submitted to Phys. Rev.
The virtual-state character of the {9}^Be 1/2^+ state in the {9}^Be({\gamma},n){8}^Be reaction
We study the character of the first excited 1/2^{+} state of {9}^Be, which is
observed as a low-lying sharp peak in the cross section of
9^Be({\gamma},n)2{\alpha} just above the {8}^Be+n threshold. Using the
{\alpha}+{\alpha}+n three-body model, we describe the ground and excited
unbound states of {9}^Be above the {\alpha}+{\alpha}+n threshold. Applying the
complex scaling method to the three-body model, we find no 1/2^{+} resonant
solutions, while the low-lying peak in the photodisintegration cross section is
reproduced in the present calculation. It is found that the low-lying peak is
dominantly explained by the 8^Be+n component. Furthermore, using the analytical
continuation of the coupling constant of the three-body interaction for the
{\alpha}+{\alpha}+n system, we discuss the virtual-state character of the
1/2^{+} state.Comment: 5 page
Four-body resonances of 7B using the complex scaling method
We study the resonance spectroscopy of the proton-rich nucleus 7B in the
4He+p+p+p cluster model. Many-body resonances are treated on the correct
boundary condition as the Gamow states using the complex scaling method. We
predict five resonances of 7B and evaluate the spectroscopic factors of the
6Be-p components. The importance of the 6Be(2+)-p component is shown in several
states of 7B, which is a common feature of 7He, a mirror nucleus of 7B. For
only the ground state of 7B, the mixing of 6Be(2+) state is larger than that of
6He(2+) in 7He, which indicates the breaking of the mirror symmetry. This is
caused by the small energy difference between 7B and the excited 6Be(2+) state,
whose origin is the Coulomb repulsion.Comment: 10 pages, 7 figure
Di-neutron correlations in 6He through Coulomb breakup reactions
The internal correlations of binary subsystems not only in the ground state but also in excited states of 6He are investigated through the Coulomb breakup reaction. For the excited states, to investigate the internal correlations, the twodimensional energy distributions of the E1 strength are calculated with respect to the relative energy in the binary subsystems, and the importance of the final state interactions are discussed. For the ground state, the E1 strength distributions are calculated by using two types of wave functions with and without strong di-neutron correlations, and the contributions from the di-neutron correlations are investigated
Coulomb Breakup Reactions in Complex-Scaled Solutions of the Lippmann-Schwinger Equation
We propose a new method to describe three-body breakups of nuclei, in which
the Lippmann-Schwinger equation is solved combining with the complex scaling
method. The complex-scaled solutions of the Lippmann-Schwinger equation (CSLS)
enables us to treat boundary conditions of many-body open channels correctly
and to describe a many-body breakup amplitude from the ground state. The
Coulomb breakup cross section from the 6He ground state into 4He+n+n three-body
decaying states as a function of the total excitation energy is calculated by
using CSLS, and the result well reproduces the experimental data. Furthermore,
the two-dimensional energy distribution of the E1 transition strength is
obtained and an importance of the 5He(3/2-) resonance is confirmed. It is shown
that CSLS is a promising method to investigate correlations of subsystems in
three-body breakup reactions of the weakly-bound nuclei.Comment: 12 pages, 6 figures, submitted to Progress of Theoretical Physics;
section 2.4 added, 2 equations added, 1 equation replace
Review Intracellular Glutathione in Cellular Immunology
Glutathione is the most abundant intracellular tripeptide thiol and acts as a reducing agent and an antioxidant. Glutathione may regulate many enzymatic and pharmacological activities by changing the intracellular redox condition. Recent studies have accumulated evidence for important roles of glutathione in full competence of lymphocytes for such as activation, proliferation and induction of cytotoxicity. A decrease in intracellular glutathione may cause malfunction of lymphocytes, immunosuppression and apoptosis. A variety of immunological functions are determined on the basis of the balance between synthesis and con-sumption of intracellular glutathione
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