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[en] During the ten-year DIII-D tokamak operating period of 1989 through 1998, major scientific advances and discoveries were made and facility upgrades and improvements were implemented. Each year, annual reports as well as journal and international conference proceedings document the year-by-year advances (summarized in Section 7). This final contract report, provides a summary of these historical accomplishments. Section 2 encapsulates the 1998 status of DIII-D Fusion Science research. Section 3 summarizes the DIII-D facility operations. Section 4 describes the major upgrades to the DIII-D facility during this period. During the ten-year period, DIII-D has grown from predominantly a General Atomics program to a national center for fusion science with participants from over 50 collaborating institutions and 300 users who spend more than one week annually at DIII-D to carry out experiments or data analysis. In varying degrees, these collaborators participate in formulating the research program directions. The major collaborating institution programs are described in Section 6

[en] The COMPASS-D tokamak has recently obtained H-mode plasmas in a single-null X-point configuration with no additional heating. Clear H-mode signatures have been observed including reduction in D_α light and the unmistakable appearance of ELMs and ELM-free periods. Recycling and gas puff can play crucial roles in achieving and terminating the H-modes. The emergence of distinct ELMs, from the apparently-random fluctuations, of the background D_α light, is usually one of progression, taking some 10s of ms rather than a sudden discontinuity. The relatively slow evolution allows for detail examination of important phenomena, such as improvements to confinement and fluid rotation. The H-mode quality improves with density, unless impurity accumulation becomes important. (author)

[en] The theory of transport across a low mode number magnetic island belt driven by the ionization instability, elongated along the last entire q rational surface, and extending beyond the separatrix leads to a number of predictions which are in agreement with observations in DIII-D, TEXTOR, ASDEX and CCT. It also suggests that transition to a regime characterized by an improved confinement should occur at a sufficiently high heating power level. (author)

[en] This first volume gives a general introduction on thermonuclear laser fusion. The plasmas physic, collision and collective interactions are developed with a description of the plasma-laser interaction, of the parametric instabilities (Brillouin, Raman, two plasmons decomposition, Langmuir waves and filamentation). (A.B.). refs., figs., tabs

[en] There are many devices have been designed and constructed. One of these devices is a dense plasma focus (DPF). Most of the devices belong either to the Mather type or the Filippoy type. In Mather type, one can classify three phases (breakdown, acceleration and collapse). In this device there are many kinds of particles and radiations emitted as a result of (D-D)fusion reaction. One of the most impotant particles produce in this reaction are the neutrons which emitted in a high yield. In this work, scaling the gun and the neutron yield which is a function of capacitor energy, discharge and pinch current have been studied. Also, a study have been concerned with paramerter that affect the gun operation. This study has shown the optimum case end the accurat operating condition of the used device. In addition to that, analytical models have been used to describe the physical state of the plasma mechanism such as the current(*****)formation and plasma dynamics.(9 tabs., 19 figs., 59 refs.)

[en] The equivalent electrical circut for the dense plasma focus (DPF) devices (Mather type) was solved assuming an instant (discharge instant ). The length of centeral electrode that calculated, was the best cosidering the value W max which represents the maximum energy transtered from the electrical circut RIC of the DPF devices was proved. The effect the external resistance values on W max that transfered across the circuit was studied.(7 tabs., 23 figs., 58 refs.)

[en] Using linear-response dielectric theory, the authors have investigated the electronic stopping power and effective charge of heavy ion beams in hot targets. For considering the charge distribution of the electrons bound to the projectile, the theoretical model of Brandt-Kitagawa is generalized to the situation of hot target. In the case of low and high velocities, the analytical expressions of the electronic stopping power and the effective charge are obtained, respectively. For low-velocity ion, it has been shown that the values of the effective charge are increased as the increasing of the values of the electron gas temperature. In certain temperature range the values of the stopping power in the hot target are increased comparing with that in the cold target. For high-velocity ions in the hydrogen plasma, the theoretical values of the stopping power obtained in present work agree very well with experimental data

[en] Profiles of H_α, H_β and H_γ lines, emitted from a TEA CO₂ laser induced silane plasma, are measured with an optical multichannel analyzer (OMA III). The experimental results show that FWHM (full width of half maximum) of the three lines increases with the main quantum number of the corresponding upper level of the transitions, i.e. Δλ_1/2(H_α)<Δλ_1/2(H_β)<Δλ_1/2(H_γ), this suggests that the dominant broadening mechanism of the lines is Stark broadening. Fitting the measured H_α profile to theoretical data of Stark broadening. two parameters of the plasma are obtained: average electron density N = 10¹⁷ cm^-3 and electron temperature T = 40,000 K. From time resolved measurements of H_β profile, a curve of electron density versus time is derived

[en] The requirements of a steady-state, D-T burning tokamak in terms of energy and particle confinement are outlined. For a plasma with central fuelling there is a net radial flow of electrons across each magnetic surface. Borrass and Pfirsch have used plasma fluid equations to show that in such a case the instability responsible for the plasma transport must be manifest as an anomalous perpendicular resistivity. Otherwise the poloidal flux is convected out leading to a steady-state skin current which would be hydromagnetically unstable. For an edge fuelled plasma the mean radial flow of electrons is zero. But there are then limitations on the beta value and severe requirements on the diffusion rates inwards and outwards of fuel ions and alpha particles respectively. An experimental test of the physics involved requires current drive and a pulse length exceeding the skin-penetration time. However some deductions can be made from the results of present experiments and these are presented