After many years of fusion research, the conditions needed for a D–T fusion reactor have been approached on the Tokamak Fusion Test Reactor (TFTR) [Fusion Technol. 21, 1324 (1992)]. For the first time the unique phenomena present in a D–T plasma are now being studied in a laboratory plasma. The first magnetic fusion experiments to study plasmas using nearly equal concentrations of deuterium and tritium have been carried out on TFTR. At present the maximum fusion power of 10.7 MW, using 39.5 MW of neutral-beam heating, in a supershot discharge and 6.7 MW in a high-βp discharge following a current rampdown. The fusion power density in a core of the plasma is ≊2.8 MW m−3, exceeding that expected in the International Thermonuclear Experimental Reactor (ITER) [Plasma Physics and Controlled Nuclear Fusion Research (International Atomic Energy Agency, Vienna, 1991), Vol. 3, p. 239] at 1500 MW total fusion power. The energy confinement time, τE, is observed to increase in D–T, relative to D plasmas, by 20% and the ni(0) Ti(0) τE product by 55%. The improvement in thermal confinement is caused primarily by a decrease in ion heat conductivity in both supershot and limiter-H-mode discharges. Extensive lithium pellet injection increased the confinement time to 0.27 s and enabled higher current operation in both supershot and high-βp discharges. Ion cyclotron range of frequencies (ICRF) heating of a D–T plasma, using the second harmonic of tritium, has been demonstrated. First measurements of the confined alpha particles have been performed and found to be in good agreement with TRANSP [Nucl. Fusion 34, 1247 (1994)] simulations. Initial measurements of the alpha ash profile have been compared with simulations using particle transport coefficients from He gas puffing experiments. The loss of alpha particles to a detector at the bottom of the vessel is well described by the first-orbit loss mechanism. No loss due to alpha-particle-driven instabilities has yet been observed. D–T experiments on TFTR will continue to explore the assumptions of the ITER design and to examine some of the physics issues associated with an advanced tokamak reactor.

Given only information that a youth who could have been tried as either an adult or as a juvenile was being tried as an adult for murder, 218 undergraduate mock jurors were able to form consistent impressions of the defendant. A very high percent of our mock jurors included a criminal or juvenile justice history as part of that impression. A very large majority of the mock jurors also said that knowledge of that criminal history would be relevant to their vote of guilty. Almost all mock jurors said they would be influenced toward voting guilty by knowledge of a previous criminal history. Few of the other components of the impression were so closely correlated with a judgment of relevance, or with a judgment that they would be influenced toward voting guilty by the knowledge of that component of the stereotype. The effect is relatively specific to knowledge of a previous criminal history. The study has limited ecological validity. Nonetheless, we raise questions about whether the fact that a youth is put on trial as an adult is inherently prejudicial, and violates the Sixth Amendment right to an impartial jury.

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The Z-pinch configuration in gas-fed devices was adapted for an ablative Pulsed Plasma Thruster (PPT). The motivation stems from the promise of the Z-pinch configuration for increasing the thrustto-power ratio and mass utilization efficiency. A series of ablative Z-pinch PPTs were constructed and their performance measured using a swinging gate thrust stand and mass ablation measurements. Several iterations of the design lead to the selection of a thruster with an augmented "spike" inner electrode for more exhaustive testing. Peak performance parameters for this configuration were found to be: I ×Ô s, Ø = 7.5 %, and T/P = 28 N/W. In order to determine whether the plamsa was pinching, photographs of the discharge were acquired using a modified thruster having transparent Plexiglas propellant and mesh sidewalls. A current sheet structure leading to a plasma pinch was observed.