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in subjects: "Neutral Particles"

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Neutral particle beam distributed data acquisition system

A distributed data acquisition system has been designed to support experiments at the Argonne Neutral Particle Beam Accelerator. The system uses a host VAXstation II/GPX computer acting as an experimenter's station linked via Ethernet with multiple MicroVAX IIs and rtVAXs dedicated to acquiring data and controlling hardware at remote sites. This paper describes the hardware design of the system, the applications support software on the host and target computers, and the real-time performance.

Date: January 1, 1987

Creator: Daly, R.T.; Kraimer, M.R. & Novick, A.H.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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''Econodump'' design for the Fermilab Direct Neutral Lepton Facility

An extensive effort has been directed toward a major redesign of the Fermilab Direct Neutral Lepton Facility (DNLF). The goal has been a very significant cost reduction of the facility, with minimal sacrifice of physics potential. Hence the name ''Econodump'' applied to the redesign effort.

Date: August 1, 1986

Creator: Childress, S.; Brown, C.; Koizumi, G.; Malensek, A.; Morfin, J.G.; Murphy, T. et al.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Possibility of New Particle Production in Heavy-Ion Collisions

Two-body decay of a particle is hypothesized in order to explain the lack of strong Z dependence of positron emission spectra in low-energy heavy ion collisions. The consequences of such a hypothesis are discussed, as well as recent theoretical and experimental work motivated by it. 50 refs. (LEW)

Date: January 1, 1986

Creator: Balantekin, A. B.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Rutherford scattering of neutral atoms: a technique for measuring plasma ion temperatures. An analysis of the applicability to the central cell plasma of TMX

Rutherford scattering of neutral particles by plasma ions is examined as a method for determining plasma ion in the central cell fo the Tandem Mirror Experiment (TMX). When a scattering configuration, consisting of a 20-keV-, 10-A-deuterium neutral beam and an energy analyzer with a 1% resolution, is arranged such that only neutral particles scattered by plasma ions over an angle of 10/sup 0/ are accepted, central-cell ion temperatures in the 30- to 1000-eV range can be measured. The count rate… more

Date: June 3, 1980

Creator: Granneman, E.H.A.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Multi-channel neutral analyzer-system

Design and calibration of a 15 channel multi-channel analyzer for analysis of energetic neutral particles escaping a hot plasma are discussed. Features of the analyzer include a frequency response from DC to 50 kHz, spatial resolution, mass resolution, and data acquisition and processing for 15 points on the energy distribution that are simultaneously recorded. Another feature of the system is the ability to radially scan the plasma. An rf ion source is used to provide ions and neutrals used fo… more

Date: September 14, 1977

Creator: Nexsen, Jr., W. E.; Turner, W. C. & Cummins, W. F.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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A Search for New Particles with Lifetime 10(-12) - 10(-14) sec in Interactions of Protons with Nucleons and Nuclei in Emulsion at 400-GeV/c

A stack of nuclear emulsions was irradiated by 400 Gev/c protons at FNAL. In this work a search for the short-lived particles has been carried out by a new method that allowed to detect secondary events (including the narrow ones) on short distances from the parent star. By measuring angles, momenta and ionizations of the secondary particles they could identify electrons and distinguish them from hadrons. In search for the decays of charged of particles on n{sub s} {ge} 3 charged relativistic p… more

Date: June 1, 1978

Creator: Chernyavsky, M. M.; Komar, A. A.; Orlova, G. I.; Salmanova, N. A. & Tretyakova, M. I.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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A MEASUREMENT OF THE POSITIVE pi- Mu DECAY LIFETIME

The lifetime for the decay of a {pi} meson into {mu} meson and neutral particle was first measured by Richardson and later by Martinelli and Panofsky. The method was the same in both cases: The fraction of {pi} mesons surviving various times of flight is measured by placing photographic detectors at various path lengths from the target. In the experiment reported here we observe the time lag between the two bursts of fluorescence due to mesons decaying in a scintillation crystal. The first burs… more

Date: May 10, 1950

Creator: Chamberlain, O.; Mozely, R.F.; Steinberger, J. & Wiegand, C.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Studies in High Current Density Ion Sources for Heavy Ion FusionApplications

This dissertation develops diverse research on small (diameter {approx} few mm), high current density (J {approx} several tens of mA/cm{sup 2}) heavy ion sources. The research has been developed in the context of a programmatic interest within the Heavy Ion Fusion (HIF) Program to explore alternative architectures in the beam injection systems that use the merging of small, bright beams. An ion gun was designed and built for these experiments. Results of average current density yield (<J>… more

Date: June 1, 2002

Creator: Chacon-Golcher, E.

Item Type: Thesis or Dissertation

Partner: UNT Libraries Government Documents Department

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Multi-fluid code simulations including anomalous non-diffusive transport of plasma and impurities in the tokamak SOL

Fast intermittent transport has been observed in the scrape-off layer (SOL) of major tokamaks including Alcator C-Mod, DIII-D, and NSTX. This kind of transport is not diffusive but rather convective. It strongly increases plasma flux to the chamber walls and enhances the recycling of neutral particles in the main chamber. We discuss anomalous cross-field convection (ACFC) model for impurity and main plasma ions and its relation to intermittent transport events, i.e. plasma density blobs and hol… more

Date: November 25, 2003

Creator: Pigarov, A. Yu; West, W. P.; Soukhanovskii, V.; Rognlien, T. D.; Maingi, R.; Lipschultz, B. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

E/sub T//sup 0/ and. pi. /sup 0/ spectra from. cap alpha cap alpha. , dd, and pp interactions at. sqrt. s/sub NN/ = 31 GeV at the CERN ISR

A review is given of E/sub T//sup 0/ and neutral pion spectra from various interactions. Inclusive single particle production at large transverse momentum from heavy nuclear targets at Fermilab and at ISR are briefly discussed, followed by some results of measurement of transverse energy emission in the central region of pA collisions. An experiment at ISR is described in which the total neutral energy emitted in the central region was measured using an electromagnetic shower counter which dete… more

Date: June 1, 1984

Creator: Tannenbaum, Michael J.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Progress in extending neutral-particle detection down to 10 eV using a Cs heat pipe for electron detachment

Results obtained from experiments to develop a neutral-particle analyzer using a cesium (Cs) heat pipe for electron detachment are described. The Cs heat pipe analyzer, which provides a high conversion efficiency for neutral hydrogen to H/sup -/, is discussed in detail. Also considered are the development of a compact velocity-energy analyzer for determining the energies of impurities escaping from the EBT plasma and the development of an absolute H/sup 0/ detector using secondary negative emis… more

Date: January 1, 1979

Creator: Barnett, C. F. & Ray, J. A.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Search for neutral leptons

At present we know of three kinds of neutral leptons: the electron neutrino, the muon neutrino, and the tau neutrino. This paper reviews the search for additional neutral leptons. The method and significance of a search depends upon the model used for the neutral lepton being sought. Some models for the properties and decay modes of proposed neutral leptons are described. Past and present searches are reviewed. The limits obtained by some completed searches are given, and the methods of searche… more

Date: December 1, 1984

Creator: Perl, Martin L.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Search for neutral, penetrating, metastable particles produced in the SLAC beam dump

A search was made for neutral objects which might be produced by 20 GeV electrons incident on the SLAC beam dump, penetrate the downstream natural shielding, and decay upstream of an electromagnetic shower calorimeter. With about 30 coulombs of electrons dumped, no candidate events were found above an energy of approx. 2 GeV. Preliminary analysis implies the 95% confidence level limit on the product of mass and lifetime of light axion-like bosons decaying primarily into two photons to be greate… more

Date: March 1, 1984

Creator: Bjorken, J.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Comparison of the total neutral energy spectra of. cap alpha cap alpha. , dd and pp interactions at the ISR

The total neutral energy spectra, E/sub TOT//sup 0/ = ..sigma../sub i/ epsilon/sub i//sup 0/, have been measured in the central region of ..cap alpha cap alpha.., dd and pp interactions at ..sqrt..s/sub NN/ = 31 GeV with an electromagnetic calorimeter covering 2..pi.. in azimuth. The data were collected in the light-ion run at the CERN ISR during August 1983. The cross section ratio of the ..cap alpha cap alpha.. to the pp interactions increases rapidly with E/TOT//sup 0/ from 7 to 10/sup 5/ in… more

Date: May 23, 1984

Creator: Tanaka, M.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Theory of contributon transport

A general discussion of the physics of contributon transport is presented. To facilitate this discussion, a Boltzmann-like transport equation for contributons is obtained, and special contributon cross sections are defined. However, the main goal of this study is to identify contributon transport equations and investigate possible deterministic solution techniques. Four approaches to the deterministic solution of the contributon transport problem are investigated. These approaches are an attemp… more

Date: October 1, 1980

Creator: Painter, J. W.; Gerstl, S. A. W. & Pomraning, G. C.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Neutrino counting in e/sup +/e/sup -/ annihilation

The physics that can be learned from studies of e/sup +/e/sup -/ ..-->.. ..gamma.. + weakly interacting particles is examined. It is shown that the physics probed by this reaction depends greatly upon the energy at which experiments are done. The experimental techniques used for these studies are emphasized, particularly the central problem of electromagnetic calorimetry. The present status of knowledge of single-photon production is presented, with a detailed look at the ASP experiment at PEP … more

Date: March 1, 1987

Creator: Burke, D.L.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Advances in low energy neutral atom imaging techniques

Recently proposed low energy neutral atom (LENA) imaging techniques use a collisional process to convert the low energy neutrals into ions before detection. At low energies, collisional processes limit the angular resolution and conversion efficiencies of these devices. However, if the intense ultraviolet light background can be suppressed, direct LENA detection is possible. We present results from a series of experiments designed to develop a novel filtering structure based on free-standing tr… more

Date: January 1, 1993

Creator: Scime, E. E.; Funsten, H. O.; McComas, D. J.; Moore, K.R. (Los Alamos National Lab., NM (United States)) & Gruntman, M. (University of Southern California, Los Angeles, CA (United States). Space Sciences Center)

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Detection of cold gas releases in space via low energy neutral atom imaging

Low energy neutral atoms (LENAs) are produced in space plasmas by charge exchange between the ambient magnetospheric plasma ions and cold neutral atoms. Under normal conditions these cold neutrals come from the terrestrial geocorona, a shroud of few-ev hydrogen atoms surrounding the Earth. As a consequence of this charge exchange, it has become possible to remotely image many regions of the magnetosphere for the first time utilizing recently developed LENA imaging technology. In addition to the… more

Date: January 1, 1993

Creator: McComas, D. J.; Funsten, H. O.; Moore, K. R.; Scime, E. E. & Thomsen, M. F.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Detection of Cold Gas Releases in Space via Low Energy Neutral Atom Imaging

Date: April 1993

Creator: McComas, D. J.; Funsten, H. O.; Moore, K. R.; Scime, E. E. & Thomsen, M. F.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Trapping of antiprotons -- a first step on the way to antihydrogen

A first step towards producing and effectively utilizing antihydrogen atoms consists of trapping antiprotons. The immediate next step must then be to control, i.e. trap the produced antihydrogen. The current state of the art in trapping antiprotons and positrons is reviewed, and the challenges in trapping the resulting neutral particles are discussed.

Date: July 1, 1993

Creator: Holzscheiter, M. H.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Advances in low energy neutral atom imaging techniques

Date: May 1, 1993

Creator: Scime, E. E.; Funsten, H. O.; McComas, D. J.; Moore, K. R. & Gruntman, M.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Gold Beam Losses at the AGS Booster Injection.

Gold beam injection efficiency decreases in proportional to the beam loss in the AGS Booster. A close look shows that large number of electrons, ions, and neutral particles are created when the gold beam scrapes wall. To investigate the neutral particle production due to the beam loss, local vacuum measurement was made during the 1998 run. It shows that the pressure created by the Booster Au{sup 31+} beam loss at injection has a 35 ms decay time constant. The beam loss created pressure bump in … more

Date: March 29, 1999

Creator: Zhang, S. Y. & Ahrens, L. A.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Instrumentation for the absorbers in the low Beta* Insertions of the LHC

Concepts are examined for the measurement of luminosity, beam-beam separation and transverse beam shape and size using the high flux of forward neutral particles produced at the low {beta}* (high luminosity) interaction points (IP's) of the LHC. At design luminosity 10{sup 34} cm{sup -2}sec{sup -1} the flux of neutrals striking the neutral beam absorbers (TAN) in front of the D2 beam separation dipoles is high enough ({approx} 8 neutrons per bunch crossing with mean energy 2.3 TeV) to allow mea… more

Date: August 1, 1998

Creator: Turner, W.C.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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A General Nonlinear Fluid Model for Reacting Plasma-Neutral Mixtures

A generalized, computationally tractable fluid model for capturing the effects of neutral particles in plasmas is derived. The model derivation begins with Boltzmann equations for singly charged ions, electrons, and a single neutral species. Electron-impact ionization, radiative recombination, and resonant charge exchange reactions are included. Moments of the reaction collision terms are detailed. Moments of the Boltzmann equations for electron, ion, and neutral species are combined to yield a… more

Date: April 6, 2012

Creator: Meier, E T & Shumlak, U

Item Type: Article

Partner: UNT Libraries Government Documents Department