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in subjects: "Phototubes"

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Hodoscope subgroup summary microchannel plate photodetectors

A brief discussion is given of the possible uses of microchannel plate photomultipliers and multichannel or multianode photodetectors at ISABELLE.

Date: January 1, 1977

Creator: Alspector, J.; Edestein, R. M.; Majka, R.; Miller, R. J. & Thaler, J.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Time resolution performance studies of contemporary high speed photomultipliers

The time resolution capabilities of prototype microchannel plate and static crossed-field photomultipliers have been investigated. Measurements were made of electron transit time, rise time, time response, single photoelectron time spread and multiphotoelectron time spread for LEP HR350 proximity focused high gain curved microchannel plate and VPM-154A/1.6L static crossed-field photomultipliers. The experimental data have been compared with results obtained with conventionally designed RCS 8850… more

Date: October 5, 1977

Creator: Leskovar, B. & Lo, C.C.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Recent developments in positron emission tomography (PET) instrumentation

This paper presents recent detector developments and perspectives for positron emission tomography (PET) instrumentation used for medical research, as well as the physical processes in positron annihilation, photon scattering and detection, tomograph design considerations, and the potentials for new advances in detectors. 117 refs., 4 figs., 4 tabs.

Date: April 1, 1986

Creator: Derenzo, S.E. & Budinger, T.F.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Use of hodoscopes at ISABELLE

A major problem for experimenters designing detectors for use at ISABELLE is the high interaction rate, one event every 25 nanoseconds at a luminosity of 10/sup 33/ cm/sup -2/ sec/sup -1/. Typical multiplicities range from a few at large angles (> approximately 45/sup 0/) to approximately 10 nearer the forward direction. This implies average rates as high as a particle every few nanoseconds. For experiments which require high luminosities, detectors must be designed which have very short (appro… more

Date: January 1, 1977

Creator: Alspector, J. & Miller, R. J.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Photomultiplier characteristics considerations for the deep underwater muon and neutrino detection system

The results of an investigation of the characteristics of photomultipliers for the Deep Underwater Muon and Neutrino Detection (DUMAND) System are discussed. The pulse-height resolution, the afterpulsing phenomena and the gain sensitivity to the ambient magnetic field have been determined for large photocathode area photomultipliers. Furthermore, the transient time difference, the single photoelectron time spread, and the collection and photocathode quantum efficiency uniformity as a function o… more

Date: February 23, 1980

Creator: Leskovar, B.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Monte Carlo calculations of the optical coupling between bismuth germanate crystals and photomultiplier tubes

The high density and atomic number of bismuth germanate (Bi/sub 4/Ge/sub 3/O/sub 12/ or BGO) make it a very useful detector for positron emission tomography. Modern tomograph designs use large numbers of small, closely-packed crystals for high spatial resolution and high sensitivity. However, the low light output, the high refractive index (n=2.15), and the need for accurate timing make it important to optimize the transfer of light to the photomultiplier tube (PMT). We describe the results of … more

Date: October 1, 1981

Creator: Derenzo, S.E. & Riles, J.K.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Cygnus Experiment at Los Alamos

The Cygnus experiment at Los Alamos National Laboratory has been designed to study, with high angular accuracy, point sources of gamma rays of energy above 10/sup 14/ eV. The experimental detector consists of an air shower array to observe gamma-ray showers and a shielded, large-area track detector to study the muon content of the showers. In this paper we present preliminary data from the array and describe its performance. 9 refs., 3 figs.

Date: January 1, 1986

Creator: Dingus, B. L.; Goodman, J. A.; Gupta, S. K.; Talaga, R. L.; Chang, C. Y.; Yodh, G. B. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Design and construction of the Donner 280-crystal positron ring for dynamic transverse section emission imaging

The design and construction of a medical imaging system for the rapid, accurate, three-dimensional imaging of positron-labeled compounds in the human body are described. Our medical research goals include quantifying blood flow and metabolism in human heart muscle and brain. The system consists of a large gantry containing lead shielding and a ring of 280 NaI(Tl) detectors that completely encircles the patient; 280 photomultiplier tubes, preamplifiers and timing discriminators; circuits that de… more

Date: September 1, 1977

Creator: Derenzo, S.E.; Banchero, P.G.; Cahoon, J.L.; Huesman, R.H.; Vuletich, T. & Budinger, T.F.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Status of the Los Alamos Anger camera

Results of preliminary tests of the neutron Anger camera being developed at Los Alamos are presented. This detector uses a unique encoding scheme involving parellel processing of multiple receptive fields. Design goals have not yet been met, but the results are very encouraging and improvements in the test procedures are expected to show that the detector will be ready for use on a small-angle scattering instrument next year. 3 refs., 4 figs.

Date: January 1, 1985

Creator: Seeger, P.A. & Nutter, M.J.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Linearity and resolution of photodiodes

Measurements are reported of the resolution and linearity of Hamamatsu S1337 Photodiodes mounted on a NaI crystal and exposed to electron energy deposits of up to 80 GeV. The results indicate that these diodes can replace photomultipliers in high-light-yield detectors such as NaI and BGO, when operated in multi-element, compact assemblies in the presence of a magnetic field.

Date: October 1, 1983

Creator: van Driel, M.A. & Sens, J.C.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Space-charge perturbation effects in photonic tubes under high irradiation

Potential perturbation effects at the cathode region of a photonic tube can occur at high intensity due to space-charge. Using appropriate photoelectron energy distribution functions, the electric field at the cathode is calculated and its effect upon the spatial/temporal resolution is examined.

Date: June 1, 1982

Creator: Kalibjian, R. & Peterson, G.G.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Initial results from the Donner 600 crystal positron tomograph

We describe a positron tomograph using a single ring of 600 close-packed 3 mm wide bismuth germanate (BGO) crystals coupled to 14 mm phototubes. The phototube preamplifier circuit derives a timing pulse from the first photoelectron, and sends it to address and coincidence circuits only if the integrated pulse height is within a pre-set window. The timing delays and pulse height windows for all 600 detectors and the coincidence timing windows are computer adjustable. An orbiting positron source … more

Date: October 1, 1986

Creator: Derenzo, S.E.; Huesman, R.H.; Cahoon, J.L.; Geyer, A.; Uber, D.; Vuletich, T. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

A method for measuring the time structure of synchrotron x-ray beams

We describe a method employing a plastic scintillator coupled to a fast photomultiplier tube to generate a timing pulse from the x-ray bursts emitted from a synchrotron radiation source. This technique is useful for performing synchrotron experiments where detailed knowledge of the timing distribution is necessary, such as time resolved spectroscopy or fluorescence lifetime experiments. By digitizing the time difference between the timing signal generated on one beam crossing with the timing si… more

Date: August 1, 1989

Creator: Moses, W. W. & Derenzo, S. E. (Lawrence Berkeley Lab., CA (USA))

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Evaluation of the Beijing Instrument Factory GDB-44F photomultipler

Characteristics have been measured for the GDB-44F 2''-diameter photomultiplier. Some typical photomultiplier characteristics - such as gain, dark current, anode output current, transit and rise times as a function of voltage between anode and cathode, and photoelectron pulse-height spectrum, the quantum-efficiency and the single-electron transit time spread were measured. Descriptions of the measuring systems were also given.

Date: December 15, 1982

Creator: Young, E. & Lo, C.C.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Beamstrahlung monitor for SLC final focus using visible wavelengths

A device is designed to detect bremsstrahlung at wide angles and wavelengths near the visible. A schematic diagram of the monitor is shown. An analysis of the performance of the monitor is given in terms of photomultiplier output and luminosity. 3 refs., 1 fig. (DWL)

Date: May 1, 1986

Creator: Bonvicini, G.; Ferrie, J.; Field, C. & Minten, A.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Comparison of systems for high speed surface flaw measurements of cartridges

Instrumentation to detect surface flaws in cartridge cases has been developed for high speed on-line inspection. Scattering of light from a line focused on the case surface indicates the presence of surface flaws and the instrumentation permits rough categorization of flaws into dents and scratches. Two methods of light detection have been implemented, and the purpose of this paper is to compare these techniques. The first technique uses fiber optics to collect the scattered light and carry it … more

Date: January 1, 1979

Creator: Swinth, K. L.; Kirihara, L. J. & Coleman, W. J.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

The Absolute, Relative and Multi-Wavelength Calibration of the Pierre Auger Observatory Fluorescence Detectors

Absolute calibration of the Pierre Auger Observatory fluorescence detectors uses a 375 nm light source at the telescope aperture. This end-to-end technique accounts for the combined effects of all detector components in a single measurement. The relative response has been measured at wavelengths of 320, 337, 355, 380 and 405 nm, defining a spectral response curve which has been normalized to the absolute calibration. Before and after each night of data taking a relative calibration of the photo… more

Date: August 1, 2007

Creator: Knapik, R.; Bauleo, P.; Becker, B.R.; Brack, J.; Caruso, R.; Fratte, C.Delle et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Preliminary studies of microchannel plate photomultiplier tube neutron detectors for flight test applications

Electrical, mechanical, thermal, and neutron response data indicate that microchannel plate photomultiplier tubes are viable candidates as miniature, ruggedized neutron detectors for flight test applications in future weapon systems.

Date: October 1, 1978

Creator: Dolan, K.W.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

The performance of a single-crystal BGO annulus as a Compton- suppression detector

We have tested a single-crystal bismuth-germanate annulus in conjunction with a high-purity germanium detector as a Compton-suppression spectrometer, and have measured gamma-ray energies of up to 6.13 MeV. 1 ref., 9 figs., 2 tabs.

Date: January 1, 1991

Creator: Ussery, L.E. (Los Alamos National Lab., NM (United States)) & Matthews, S.K. (George Washington Univ., Washington, DC (United States))

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Multi-energy neutron detector for counting thermal neutrons, high-energy neutrons, and gamma photons separately

The need for an improved, compact, wide-energy neutron detector for neutron monitoring and surveillance in nuclear facilities and weapons storage, where a possibility of fission excursion exists, led to development of a single detector that is sensitive to thermal neutrons, high-energy neutrons, and gamma radiation. Previously, separate detectors have been required to count these three different radiations separately. This development is a great advantage when experimental space is limited. 4 f… more

Date: January 1, 1989

Creator: Chiles, M. M. & McElhaney, S. A.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Tritium monitoring system for near ambient measurements

This paper describes the current status of research on an improved tritium measurement system at the Oak Ridge National Laboratory (ORNL) for the US Navy. Present tritium-in-air monitoring systems installed by the Navy can reliably measure to less than 10 {mu}Ci/m{sup 3}, but medical and safety issues are pushing measurement needs to below 1 {mu}Ci/m{sup 3}, which is equivalent to 1--10 nCi/ml in liquid samples, using calcium metal converter. A significant effort has been expended over the past… more

Date: January 1, 1991

Creator: Falter, K.G. & Bauer, M.L.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Background fitting for electron energy-loss spectra

Microanalysis using electron energy loss spectroscopy is now well established. In order to assess true edge profiles and obtain integrated intensities of the inner shell ionization edges of interest, it is first necessary to subtract the background. Usually a simple inverse power law is used, but for some spectra this form does not fit well. An alternative form which results in superior fits is described.

Date: 1981~

Creator: Bentley, James; Lehman, G.L. & Sklad, P.S.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Test of lead glass shower counters

Lead glass counters made of wedge shaped blocks of SF6 were tested with positrons at SLAC. The beam energy ranged from 2 to 17.5 GeV. Energy dependence and beam position dependence of pulse height and energy resolution were studied with lead glass blocks of various lengths. The effect of a BK-7 light guide on pulse height was clearly observed. Degradation of the energy resolution due to aluminum absorbers of various lengths was investigated. A mesh type photomultiplier was also tested.

Date: October 1, 1983

Creator: Kawabata, S.; Ogawa, K.; Sugahara, R.; Sumiyoshi, T.; Takahashi, K.; Awaji, N. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Sudbury Neutrino Observatory

This document is a technical progress report on work performed at the University of Pennsylvania during the current year on the Sudbury Neutrino Observatory project. The motivation for the experiment is the measurement of neutrinos emitted by the sun. The Sudbury Neutrino Observatory (SNO) is a second generation dedicated solar neutrino experiment which will extend the results of our work with the Kamiokande II detector by measuring three reactions of neutrinos rather than the single reaction m… more

Date: March 1, 1992

Creator: Beier, E.W.

Item Type: Report

Partner: UNT Libraries Government Documents Department