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Cross sections and analyzing powers are calculated for the l60(p,2p)15N and 40Ca(p,2p)39K reactions at an incident energy of Ep = 200 MeV within the framework of the self-consistent and relativistic finite-range distorted wave impulse approximation. The dynamics of the (p,2p) reaction is, for the first time, treated in a self-consistent manner, where single-particle bound state wave functions are calculated from the relativistic meanfields produced by the Dirac-Hartree model and distorted wave functions are calculated from the optical potentials obtained by folding nuclear densities with the Horowitz interaction.This model gives a unified description of the (p,2p) reactions with different target nuclei using the same basic parameters, i.e., mass and coupling constants for 0', wand p mesons, on which the Dirac-Hartree model depends. Our calculation results show that this model satisfactorily explains the observables for both reactions simultaneously. It is also shown that the self-consistent optical potentials employed in this work are valid for a wide range of elastic proton energies and give almost the same results for the observables, except for their 10 rv 20% smaller values for the cross sections when compared with the global Dirac optical potentials. §1. Introduction 91 Finite nuclei have long been treated as many-body systems consisting of nonrelativistic nucleons. These treatments are based on the fact that the binding energy of a nucleon in a nucleus is sufficiently small compared with its rest mass.Recent relativistic approaches for finite nuclei, however, have revealed their importance even for describing ground state properties. Following preceding works, 1) -5) Horowitz and Serot 6) considered a finite nucleus as a many-body system composed of mesons and Dirac nucleons and applied a relativistic quantum field theory to it. Their Dirac-Hartree calculations successfully explained the observed spin-orbit splittings of the nucleon levels as well as the measured densities. The other relativistic approach came from the Dirac phenomenology by Clark et aI., 7) who studied proton-nucleus elastic scattering in the intermediate energy range. In their work, the proton was treated as a Dirac particle moving in the phenomenological scalar and vector optical potentials. They found that proton elastic data, especially spin observables, could be fit quite satisfactorily using the phenomenological relativistic optical potentials. Subsequently, the microscopic approach for the relativistic optical potential showed that the potential could be calculated from a relativistic N N interaction and the relativistic impulse approximation (RIA). 8) -10) This series of works implies the possibility of a self-consistent description of *) Present address:

Within the framework of the relativistic distorted wave impulse approximation (DWIA), we investigate the sensitivity of the analyzing power -for exclusive proton knockout from the 3s 1/2 , 2d 3/2 and 2d 5/2 states in 208 Pb, at an incident laboratory kinetic energy of 202 MeV, and for coincident coplanar scattering angles (28.0 • , −54.6 • ) -to different distorting optical potentials, finite-range (FR) versus zero-range (ZR) approximations to the DWIA, as well as medium-modified coupling constants and meson masses. Results are also compared to the nonrelativistic DWIA predictions based on the Schrödinger equation. Whereas the nonrelativistic model fails severely, both ZR and FR relativistic DWIA models provide an excellent description of the data. For the FR predictions, it is necessary to invoke a 20% reduction of sigma-nucleon and omega-nucleon coupling constants as well as for σ-, ρ-and ω-meson masses, by the nuclear medium. On the other hand, the ZR predictions suggest that the strong interaction in the nuclear medium is adequately represented by the free nucleon-nucleon interaction associated with the impulse approximation. We also demonstrate that, although the analyzing power is relatively insensitive to the use different relativistic global optical potential parameter sets, the prominent oscillatory behavior of this observable is largely attributed to distortion of the scattering wave functions relative to their plane wave values.

Within the framework of the relativistic distorted wave impulse approximation (DWIA), we investigate the sensitivity of complete sets of polarization transfer observables

For the achievement of steady-state fusion power plant, non-inductively current-driven plasma operation should be maintained in tokamak fusion reactors. Total non-inductive current is a summation of bootstrap current proportional to the plasma pressure gradient and externally driven non-inductive current such as neutral beam driven current. Especially in order to establish a commercial reactor, it is necessary to reduce the amount of external current-drive power and to maintain the majority of the plasma current with bootstrap current. Burning plasma has high autonomy, so the change in current density profile including changes in particle and heat transports should be checked. In this study time-evolution analysis of the current density profile for burning plasmas in the ITER machine has been conducted by using 2.0-dimensional equilibrium, 1.5-dimensional-transport code (TOTAL code). Here current-diffusive ballooning mode model was adopted as a heat transport model. It is concluded that external current-drive is required both in the center and near the periphery of the plasma in order to maintain steady-state profiles of temperature and density with high bootstrap current fraction.