The Sudbury Neutrino Observatory

The Sudbury Neutrino Observatory is a second generation water Cherenkov detector designed to determine whether the currently observed solar neutrino deficit is a result of neutrino oscillations. The detector is unique in its use of D2O as a detection medium, permitting it to make a solar model-independent test of the neutrino oscillation hypothesis by comparison of the charged- and neutral-current interaction rates. In this paper the physical properties, construction, and preliminary operation of the Sudbury Neutrino Observatory are described. Data and predicted operating parameters are provided whenever possible.Comment: 58 pages, 12 figures, submitted to Nucl. Inst. Meth. Uses elsart and epsf style files. For additional information about SNO see http://www.sno.phy.queensu.ca . This version has some new reference

Highly-parallelized simulation of a pixelated LArTPC on a GPU

The rapid development of general-purpose computing on graphics processing units (GPGPU) is allowing the implementation of highly-parallelized Monte Carlo simulation chains for particle physics experiments. This technique is particularly suitable for the simulation of a pixelated charge readout for time projection chambers, given the large number of channels that this technology employs. Here we present the first implementation of a full microphysical simulator of a liquid argon time projection chamber (LArTPC) equipped with light readout and pixelated charge readout, developed for the DUNE Near Detector. The software is implemented with an end-to-end set of GPU-optimized algorithms. The algorithms have been written in Python and translated into CUDA kernels using Numba, a just-in-time compiler for a subset of Python and NumPy instructions. The GPU implementation achieves a speed up of four orders of magnitude compared with the equivalent CPU version. The simulation of the current induced on 10^3 pixels takes around 1 ms on the GPU, compared with approximately 10 s on the CPU. The results of the simulation are compared against data from a pixel-readout LArTPC prototype

The DUNE far detector vertical drift technology. Technical design report

DUNE is an international experiment dedicated to addressing some of the questions at the forefront of particle physics and astrophysics, including the mystifying preponderance of matter over antimatter in the early universe. The dual-site experiment will employ an intense neutrino beam focused on a near and a far detector as it aims to determine the neutrino mass hierarchy and to make high-precision measurements of the PMNS matrix parameters, including the CP-violating phase. It will also stand ready to observe supernova neutrino bursts, and seeks to observe nucleon decay as a signature of a grand unified theory underlying the standard model. The DUNE far detector implements liquid argon time-projection chamber (LArTPC) technology, and combines the many tens-of-kiloton fiducial mass necessary for rare event searches with the sub-centimeter spatial resolution required to image those events with high precision. The addition of a photon detection system enhances physics capabilities for all DUNE physics drivers and opens prospects for further physics explorations. Given its size, the far detector will be implemented as a set of modules, with LArTPC designs that differ from one another as newer technologies arise. In the vertical drift LArTPC design, a horizontal cathode bisects the detector, creating two stacked drift volumes in which ionization charges drift towards anodes at either the top or bottom. The anodes are composed of perforated PCB layers with conductive strips, enabling reconstruction in 3D. Light-trap-style photon detection modules are placed both on the cryostat's side walls and on the central cathode where they are optically powered. This Technical Design Report describes in detail the technical implementations of each subsystem of this LArTPC that, together with the other far detector modules and the near detector, will enable DUNE to achieve its physics goals

Development of large rectangular ceramic insulators for ion accelerators for the neutral-beam program

The need for structures that are resistant to damage for 14 MeV neutrons, are bakeable, and that can be closely packed together, has resulted in the intensive development of rectangular brazed ceramic insulators for ion accelerators. The development of two candidate materials, machinable glass ceramic and alumina, is described along with the ceramic-to-metal brazing techniques developed for each material. The microstructures of the brazed joints are examined and the results of microprobe studies presented. It has been found that the surfaces produced by different machining methods have a significant effect on the strength of brazed joints to the machinable glass ceramic. Lapped surfaces have given bond strengths up to three times those produced with other surfaces. Successful full-size brazes have been realized between alumina and titanium and between machinable glass and titanium. Vacuum tight joints between machinable glass and titanium have not been reliably achieved and more work is needed before brazing techniques to this promising new material are fully understood

Japan-G Dataset, Gun and Kuni Maps (1887)

Gun sketch maps digitized from Kyudaka kyuryo torishirabecho 旧高旧領取調帳 by Motoi Kimura 木村礎. 205 Attributes, primarily historical variables and analytical derived variables. Original data does not include Hokkaido. (updated version includes completed Kuni maps, including Hokkaido). Compilers: Tsunetoshi Mizoguchi, G. W illiam Skinner, Catherine Koehler, Kyle Matoba, and Mark Henderson. Editors: Merrick Lex Berman, Fabian Drixler, and Akihiro Tsukamoto

The USAID Agroforestry Systems An Alternative to Meeting Haiti's Food, Fiber and Fuel Needs

Because of a high ratio of population to arable land, extensive cropping and grazing practices, and ever increasing demand for fuel and wood products, Haiti's once abundant forestry resources rapidly are disappearing. The country's current forest resources are unlikely to meet growing levels of demand beyond this century unless consumption and production trends are reversed. Concurrently, the removal of forest cover is causing serious erosion problems and reductions of agricultural productivity. The US Agency for International Development has mounted a program of agroforestry that emphasizes the rapid propagation and distribution of improved multipurpose tree crop species throughout Haiti to address these problems. The underlying premise of the program is that Haitian peasants will intercrop forest, fruit and food crops and indirectly address the problems of deforestation and erosion provided acceptable returns are foreseen from such practices. Through Technical and socioeconomic research, efficient nursery techniques, and extension through local organizations, the program has planted over 11 million rapidly maturing multipurpose hardwood and fruit tree seedlings on 20,000 small-farmer plots. Many farmers who participated early in the program, which commenced in the spring of 1981, are now harvesting hardwood species for lumber and/or fuel needs

ON FABRICATION AND BRAZING OF 15A, 120 keV CONTINUOUS DUTY ACCELERATOR GRID ASSEMBLIES

The development of high intensity neutral beam injectors at the Lawrence Berkeley Laboratory has progressed from relatively low duty cycle, low energy devices to the next generation of continuous duty high energy units. The earlier pulsed versions were designed with edge cooled grid structures described ·in a previous publication. The prerequisites set by the higher duty cycle devices no longer allow the edge cooling methods to be employed. Hollow molybdenum grid rails with deionized cooling water flowing at pressures of approximately 1.73 x 10{sup 6}Pa (250 PSI) at from 1.135 to 1.89 liters per minute (.3 to .5 GPM) are brazed to Type 304L stainless steel rail holders

Wernicke Aphasia

This chapter describes life and work of Carl Wernicke, whose name is related to a specific aphasia syndrome