Charge-Focusing Readout of Time Projection Chambers

Time projection chambers (TPCs) have found a wide range of applications in particle physics, nuclear physics, and homeland security. For TPCs with high-resolution readout, the readout electronics often dominate the price of the final detector. We have developed a novel method which could be used to build large-scale detectors while limiting the necessary readout area. By focusing the drift charge with static electric fields, we would allow a small area of electronics to be sensitive to particle detection for a much larger detector volume. The resulting cost reduction could be important in areas of research which demand large-scale detectors, including dark matter searches and detection of special nuclear material. We present simulations made using the software package Garfield of a focusing structure to be used with a prototype TPC with pixel readout. This design should enable significant focusing while retaining directional sensitivity to incoming particles. We also present first experimental results and compare them with simulation.Comment: 5 pages, 17 figures, Presented at IEEE Nuclear Science Symposium 201

Testing if healthy perfectionism enhances academic achievement in Australian secondary school students

Although considerable evidence has confirmed that measures of intelligence and conscientiousness substantially predict academic achievement, other personality variables have attracted only limited research. The purpose of this study was to test the extent to which intelligence and personality variables, including perfectionism, accounted for academic grades. Participants were 180 (65 males) secondary school students in years 11-12. They completed tests for fluid and crystallised abilities (Gf, Gc), Conscientiousness (C), Openness to Experience (O), Neuroticism (N), Need for Cognition (NFC) and the Frost Multidimensional Perfectionism Scale, which was used to define healthy perfectionism (HP) and unhealthy perfectionism (UHP). Gender differences for all measures were negligible and not considered further. One aspect of HP (personal standards) overlapped moderately with NFC but HP and NFC appeared to be different constructs. Hierarchical regression found that Gf, Gc and C together accounted for 27% of variance in academic grade, with HP explaining an additional 6%. Further contribution from NFC was not statistically significant. N correlated with UHP but did not impact grade. Higher concern about parental criticisms correlated (r = -.27) with lower academic grade.Elizabeth Thorpe & Ted Nettelbec

Science aspects of a 1980 flyby of Comet Encke with a Pioneer spacecraft

Results are presented of an investigation of the feasibility of a 1980 flyby of Comet Encke using a Pioneer class spacecraft. Specific areas studied include: science objectives and rationale; science observables; effects of encounter velocity; science encounter and targeting requirements; selection and description of science instruments; definition of a candidate science payload; engineering characteristics of suggested payload; value of a separable probe; science instruments for a separable probe; science payload integration problems; and science operations profile

Science aspects of 1980 ballistic missions to comet Encke, using Mariner and Pioneer spacecraft

Science aspects of a 1980 spacecraft reconnaissance of Comet Encke are considered. The mission discussed is a ballistic flyby (more exactly, a fly-through) of P/Encke, using either a spin stabilized spacecraft, without despin of instruments, or a 3-axis stabilized spacecraft

Scientific possibilities of a solar electric powered rendezvous with comet Encke

The minimum scientific spacecraft instrumentation is considered that is likely to result in as complete an understanding of the composition, structure, and activity of a cometary nucleus as is possible without landing on it. The payload will also give useful results on secondary goals of a better understanding of physical processes in the inner and outer coma. Studies of composition, by means of an actual landing on the surface, details of the internal structure of the nucleus, and sample return were considered beyond the scope of this mission