12 research outputs found
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Spin excitations in pion inelastic scattering
The data on spin excitations observed in pion inelastic scattering are reviewed. A predominant feature of this process is the selectivity with which high-spin unnatural-parity states are excited. Constant-q excitation functions have proven valuable in identifying unnatural-parity states because of the unique signature of ..delta..S = 1 transitions. It has recently been shown that angular distributions measured for transitions to natural-parity states are quite different for ..delta..S = 0 and ..delta..S = 1 transitions. Pion scattering should continue to prove useful in studying the spin structure of nuclear transitions because of the sensitivity of both excitation functions and angular distributions to the spin transferred to the nucleus. In particular, pion scattering measurements may be helpful in searches for spin-mode giant resonances. In addition to the ability to distinguish transitions dominated by ..delta..S = 1, comparisons of ..pi../sup +/ and ..pi../sup -/ scattering can be used to determine the relative contributions of neutrons and protons to inelastic transitions. In each N not equal to Z nucleus studied there have been large ..pi../sup +//..pi../sup -/, asymmetries observed for some transitions to stretched states. This results in information that is not obtainable from 180/sup 0/ electron scattering
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Reliability estimates for large satellite memories in low earth orbits
Los Alamos and Sandia National Laboratories are building an ultrasoft x-ray space telescope experiment, designed to be flown on a ''cheap-sat.'' Reliability estimates for the combined total dose and single event environments are given for the on-board memories as large as 1 gigabit. 4 refs., 4 figs., 1 tab
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Atmospheric measurements using a scanning, solar-blind Raman Lidar
The study of the water cycle by Lidar has many applications. Because micro-scale structures can be identified by their water content, the technique offers new opportunities to visualize and study the phenomena. There are applications to many practical problems in agricultural and water management as well as at waste storage sites. Conventional point sensors are limited and are inappropriate for use in complex terrain or varied vegetation and cannot be extrapolated over even modest ranges. To this end, techniques must be developed to measure the variables associated with evapotranspirative processes over large areas and varied surface conditions. A scanning water-Raman Lidar is an ideal tool for this task in that it can measure the water vapor concentration rapidly with high spatial resolution without influencing the measurements by the presence of the sensor. 3 refs., 5 figs., 1 tab
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Remote detection of atmospherically dispersed vegetative cells using fluorescence LIDAR
A uv fluorescence LIDAR system is employed for the long range detectio of atmospherically dispersed biological particles (e.g. Bacillus thuringiensis) released from an aerosol generator. 1 ref., 2 figs
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“Geant Simulation of Muon Cooling Rings,” “Ionization Cooling Ring for Muons,” “Geant Simulation of Six-Dimensional Cooling of Muon Beams in Ring Coolers,” “Recent Progress in Neutrino Factory and Muon Collider Research Within the Muon Collaboration,” “Towards the Higgs Factory/Muon Collider,” “Status of R&D on Neutrino Factories and Muon Colliders,” “Feasibility Study-II of a Muon-Based Neutrino Source,” “A Muon Collider as a Higgs Factory,” “Higgs Factory Muon Collider,” “A Muon Collider as a Higgs Factory,” “A Feasibility Study of a Neutrino Source Based on a Muon Storage Ring,” “Status of Muon Collider Research and Development and Future Plans,”
FINAL TECHNICAL REPORT FOR DOE AWARD DE-FG02-03ER41267 NEUTRINO FACTORY AND MUON COLLIDER FELLOW 1. Introduction By providing an intense, well controlled, well characterized, narrow beam of muon neutrinos (’s) and electron antineutrinos ( ’s) from the decay of muons (’s) in a storage ring, a neutrino factory can advance neutrino physics beyond the current round of approved and proposed experiments using conventional neutrino beams produced from a beam of decaying pions and kaons [1, 2]. There is no other comparable single clean source of electron neutrinos (from the decay of +’s) or antineutrinos. A muon storage ring producing 1019 to 1021 muon decays per year should be feasible. These intense neutrino beams can be used to study neutrino oscillations and possible CP violation. An entry-level muon storage ring that could provide 1019 decays per year would allow a determination of the sign of and a first measurement of sin2213 for favorable values of this parameter. An improved muon storage ring system that could provide 1020 muon decays per year would allow measurement of sin2213 to 104. A high performance muon storage ring capable of providing more than 1020 muon decays per year would allow the exciting possibility of a measurement of CP violation in the leptonic sector. An intense cold muon beam at the front end of a neutrino factory could enable a rich variety of precision muon physics, such as a more precise measurement of the muon anomalous magnetic moment (g – 2) and searches for e and N e N conversion [3]. In addition, colliding beams of + and in a muon collider can provide an effective “Higgs factory” or multi-TeV center-of-mass energy collisions [4]. A muon collider will be the best way to study the Higgs bosons associated with supersymmetric theories and may be necessary to discover them. Two neutrino factory feasibility studies have been carried out in the U.S. [5, 6]. International design efforts are now under way. The International Neutrino Factory and Superbeam Scoping Study (ISS) [7] began at the NuFact05 Workshop in June 2005 with the goals of elaborating the physics case, defining the baseline options for such a facility and its neutrino detectors, and identifying the required R&D program to lay the foundations for a complete design study proposal, and an International Design Study of the Neutrino Factory is beginning. These studies entail iterative cost and technical difficulty evaluations, thereby providing guidelines for the advancing R&D program. One of the central subsystems of a neutrino factory or muon collider is the muon cooling system. The muon beam is cooled to increase the phase space density and allow the muons to pass through smaller apertures, thus reducing the cost of the following accelerator systems. This cooling is accomplished through ionization cooling, in which the beam is passed through liquid hydrogen absorbers and then accelerated in RF cavities to restore the longitudinal momentum. Ionization cooling was proposed more than twenty years ago [8] but has not yet been demonstrated in practice. The International Muon Ionization Cooling Experiment (MICE) [9, 10] seeks to build and operate a muon-cooling device of a design proposed in Feasibility Study-II [6]. In addition to cooling the muons, MICE includes apparatus to measure the performance of the device. The experiment will be carried out by a collaboration of physicists from the U.S., Europe, and Japan at the Rutherford Appleton Laboratory in the U.K. MICE will begin operation in late 2007. Successful performance of the MICE experiment will provide the understanding needed to design a complete neutrino factory, in which the muons are cooled, accelerated, circulated in a storage ring, and decay to produce the neutrino beam. The first neutrino factory might be built in the U.S., Europe, or Japan. A Muon Collider Task Force (MCTF) has recently been organized at Fermilab