89 Matching Results

Search Results

Advanced search parameters have been applied.
in creator/contributor: "Fischer, J."  
Results: 1 - 24 next
open access

Measurement of energy loss in the region of relativistic rise for particle identification

Description: The following boundary conditions are desirable for particle detectors providing momentum and mass measurement in a magnetic field. A multilayer drift chamber of the socalled ''bicycle'' type with a radius of 1.5 m is considered. The useful track length will be l/sub min/ = 1.3 m for a straight track at 90/sup 0/ to the beam axis. Two examples for possible subdivisions of this volume are chosen: (1) number of layers, n = 200 and thickness/layer, x = 6.5 mm; and (2) n = 56 and x = 23 mm. An anal… more
Date: January 1, 1977
Creator: Fischer, J.; Okuno, H. & Walenta, A.H.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

A many particle-tracking detector with drift planes and segmented cathode readout

Description: We describe the design and performance of a detector system for tracking charged particles in an environment of high track density and rates up to 1 MHz. The system operates in the forward spectrometer of the BNL Heavy Ion experiment E814 and uses principles of general interest in high rate, high multiplicity applications such as at RHIC or SSC. We require our system to perform over a large dynamic range, detecting singly charged particles as well as fully ionized relativistic {sup 28}Si. Resul… more
Date: January 1, 1990
Creator: Fischer, J.; Lissauer, D.; Ludlam, T.; Makowiecki, D.; O'Brien, E.; Radeka, V. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Avalanche localization and its effects in proportional counters

Description: Avalanche development around the anode wire in a gas proportional counter is investigated. In the region of proportional gas amplification, the avalanche is found to be well localized on one side of the anode wire, where the electrons arrive along the field lines from the point of primary ionization. Induced signals on electrodes surrounding the anode wire are used to measure the azimuthal position of the avalanche on the anode wire. Practical applications of the phenomena such as left-right as… more
Date: November 1, 1977
Creator: Fischer, J.; Okuno, H. & Walenta, A.H.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Development program on pressurized fluidized-bed combustion. Annual report, July 1, 1974--June 30, 1975

Description: The feasibility of using fluidized-bed combustors in power and steam plants is being evaluated. The concept involves burning fuels such as coal in a fluidized bed of either a naturally occurring, calcium-containing limestone or dolomite or in a synthetically prepared calcium-containing stone. The calcium oxide in the stone reacts with the sulfur released during combustion to form calcium sulfate, which remains in the bed, thus decreasing the level of SO/sub 2/ in the flue gas. Levels of NO/sub … more
Date: July 1, 1975
Creator: Vogel, G.J.; Cunningham, P. & Fischer, J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Developments in gas detectors for synchrotron x-ray radiation

Description: New results on the physical limitations to position resolution in gas detectors for x-rays (approx. =3 to 20 keV) due to the range of photoelectrons and Auger electrons are discussed. These results were obtained with a small gap detector in which position readout was accomplished by using a very low noise centroid finding technique. A description is given of position sensitive detectors for medium rates (a few x 10/sup 5/ photons per second), using delay line readout, and for very high rates (a… more
Date: September 1, 1985
Creator: Fischer, J.; Radeka, V. & Smith, G.C.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Physical Parameters in Synthoil Process, Quarterly Report: January-March 1976

Description: This work is being done in support of the development of processes for converting coal to liquid fuel of low sulfur content, suitable for use in power production. Most of the effort is intended to produce information applicable to the SYNTHOIL Process. In the SYNTHOIL Process for converting coal to a low-sulfur fuel oil, coal is liquefied and hydro-desulfurized in a turbulent-flow, catalytic packed-bed reactor. A slurry of coal in recycled oil is reacted with hydrogen at 450 degrees C and 2,000… more
Date: 1976?
Creator: Fischer, J.; Lo, R.; Nandi, S.; Fredrickson, D.; Bump, T. R.; Mulcahey, T. P. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Gasification of Chars Produced Under Simulated in situ Processing Conditions Quarterly Report: January-March 1976

Description: This effort is being directed toward support studies for the national endeavor on in situ coal gasification. This task involves the investigation of reaction-controlling variables and product distributions for the gasification of both coals and chars utilizing steam and oxygen. Included in this task is the investigation of the effects of using brackish water as the water supply. The high-pressure char gasification system has been received from the manufacturer and is currently undergoing testin… more
Date: 1976?
Creator: Fischer, J.; Lo, R.; Young, J. & Jonke, A. A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Coal Liquefaction Support Studies

Description: A development program is being carried out to obtain information applicable to the SYNTHOIL process for converting coal to liquid fuel of low sulfur content. This report presents information on (1) the design of a calorimeter to measure heat of reaction of hydrogen with coal slurries, (2) the design of apparatus and calculations for measuring coefficients of heat transfer from SYNTHOIL process feed and effluent products to process vessel walls, (3) tests on the use of additives to facilitate th… more
Date: 1976?
Creator: Fischer, J.; Bump, T. R.; Mulcahey, T. P.; Jonke, A. A.; Lo, R.; Nandi, S. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Gasification of Chars Produced Under Simulated in situ Processing Conditions Quarterly Report: October-December 1975

Description: This effort is being directed toward support studies for the national endeavor on in situ coal gasification. This task involves the investigation of reaction-controlling variables and product distributions for the gasification of both coals and chars utilizing steam and oxygen. Included in this task is the investigation of the effects of using brackish water as the water supply. The high-pressure char gasification system has been received from the manufacturer and is currently undergoing testin… more
Date: 1976
Creator: Fischer, J.; Lo, R.; Young, J. & Jonke, A. A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Physical Parameters in Synthoil Process, Quarterly Report: October-December 1975

Description: This work is being done in support of the development of processes for converting coal to liquid fuel of low sulfur content, suitable for use in power production. Most of the effort is intended to produce information applicable to the SYNTHOIL Process. In the SYNTHOIL Process for converting coal to a low-sulfur fuel oil, coal is liquefied and hydro-desulfurized in a turbulent-flow, catalytic packed-bed reactor. A slurry of coal in recycled oil is reacted with hydrogen at 450 degrees C and 2,000… more
Date: 1976
Creator: Fischer, J.; Lo, R.; Nandi, S.; Fredrickson, D.; Bump, T. R.; Mulcahey, T. P. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Review and Analysis of Spray Combustion as Related to Alternative Fuels

Description: A review was conducted during the period of mid-June to mid-August 1979, of the literature on spray combustion. Particular attention has been paid to theoretical and experimental work on droplet and spray combustion applicable to the use of alternate fuels, mainly liquid fuels derived from coal and shale.
Date: September 1979
Creator: Black, C. H.; Chiu, H. H.; Fischer, J. & Clinch, J. M.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Coal Liquefaction Support Studies

Description: A development program is being carried out to obtain information applicable to the SYNTHOIL process for converting coal to liquid fuel of low sulfur content. This report presents information on (1) the design of a calorimeter to measure heat of reaction of hydrogen with coal slurries, (2) the design of apparatus and calculations for measuring coefficients of heat transfer from SYNTHOIL process feed and effluent products to process vessel walls, (3) tests on the use of additives to facilitate th… more
Date: 1976?
Creator: Fischer, J.; Bump, T. R.; Mulcahey, T. P.; Jonke, A. A.; Lo, R.; Nandi, S. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Gasification of Chars Produced Under Simulated in situ Processing Conditions

Description: This effort is being directed toward support studies for the national endeavor on in situ coal gasification. This task involves the investigation of reaction-controlling variables and product distributions for the gasification of both coals and chars utilizing steam and oxygen. Included in this task is the investigation of the effects of using brackish water as the water supply. The high-pressure char gasification system has been received from the manufacturer and is currently undergoing testin… more
Date: December 1976
Creator: Fischer, J.; Lo, R.; Young, J. & Jonke, A. A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Coal Liquefaction Support Studies

Description: A development program is being carried out to obtain information applicable to the SYNTHOIL process for converting coal to liquid fuel of low sulfur content. This report presents information on (1) the design of a calorimeter to measure heat of reaction of hydrogen with coal slurries, (2) the design of apparatus and calculations for measuring coefficients of heat transfer from SYNTHOIL process feed and effluent products to process vessel walls, (3) tests on the use of additives to facilitate th… more
Date: 1977?
Creator: Fischer, J.; Bump, T. R.; Mulcahey, T. P.; Jonke, A. A.; Lo, R.; Nandi, S. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Laboratory Support for in situ Gasification Reaction Kinetics. Quarterly Report, October-December 1976

Description: This work, which is part of the ANL energy program for ERDA, is directed toward studies for the national endeavor on in situ coal gasification. The objective of this work is to determine the reaction-controlling variables and reaction kinetics for gasification of chars resulting when coal is pyrolyzed in underground gasification. The reactions to be studied include steam-char, carbon dioxide-char, hydrogen-char, and water gas shift reaction. Discussed in this report are the effects on the reac… more
Date: January 1977
Creator: Fischer, J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Proposal for a study of laser acceleration of electrons using micrograting structures at ATF (Phase 1)

Description: We propose to investigate new methods of particle acceleration using a short-pulse CO{sub 2} laser as the power source and grating-like structures as accelerator cavities''. Phase I of this program is intended to demonstrate the principle of the method. We will focus the laser light to a 3 mm line on the surface of the microstructure. The structure is used to transform the electric field pattern of the incoming transversely polarized laser beam to a mode which has a component along the electron… more
Date: October 29, 1989
Creator: Chen, W.; Claus, J.; Fernow, R. C.; Fischer, J.; Gallardo, J. C.; Kirk, H. G. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Photoelectron range limitations to the spatial resolution for x-rays in gas proportional chambers

Description: Measurements have been made, for x-ray energies from a few keV to 18 keV, of the limiting spatial resolution caused by the finite range of the photoelectron, or electrons, created when an x-ray is absorbed in the gas of a proportional chamber. In hydrocarbon gases such as methane and ethane, where the photoelectron receives the bulk of the x-ray energy, the limiting spatial resolution is found to vary as a power law of x-ray energy. In argon and xenon, at an x-ray energy approximately twice tha… more
Date: November 1, 1983
Creator: Smith, G.C.; Fischer, J. & Radeka, V.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

High current photoemission with 10 picosecond uv pulses

Description: The quantum efficiency and the optical damage threshold of various metals were explored with 10 ps, 266 nm, UV laser pulses. Efficiencies for Cu, Y, and Sm were: 1.4, 5, and 7 {times} 10{sup {minus}4}, with damage thresholds about 100, 10, and 30 mJ/cm{sup 2}. This would permit over 1 {mu}C/cm{sup 2} or current densities exceeding 100 kA/cm{sup 2}. High charge and current densities of up to 66 kA/cm{sup 2} were obtained on 0.25 mm diam cathodes, and 21 kA/cm{sup 2} on a 3 mm diam yttrium cathod… more
Date: June 1, 1990
Creator: Fischer, J.; Srinivasan-Rao, T. & Tsang, T.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Photoemission using femtosecond laser pulses

Description: Successful operation of short wavelength FEL requires an electron bunch of current >100 A and normalized emittance < 1 mm-mrad. Recent experiments show that RF guns with photocathodes as the electron source may be the ideal candidate for achieving these parameters. To reduce the emittance growth due to space charge and RF dynamics effects, the gun may have to operate at high field gradient (hence at high RF frequency) and a spot size small compared to the aperture. This may necessitate the lase… more
Date: October 1, 1991
Creator: Srinivasan-Rao, T.; Tsang, T. & Fischer, J.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Position detection of 17-25 keV x-rays in krypton and xenon with a resolution of 18-50 m (FWHM)

Description: Measurements have been made of x-ray position resolution in a proportional chamber with both Kr/10% CO2 and Xe/10% CO2, for the x-ray energy region 17 to 25 keV. Position resolutions in the range of 18 to 50 m (FWHM) are obtained in krypton, and in the range 50 to 100 m (FWHM) for xenon. These results are interpreted in terms of the physical limitation to resolution due to the range of photoelectrons and Auger electrons emitted from the x-ray absorbing atom.
Date: October 1, 1985
Creator: Fischer, J.; Radeka, V. & Smith, G.C.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

X-ray position detection in the region of 6. mu. m RMS with wire proportional chambers

Description: We have developed a MWPC system for x-ray detection with a position resolution in the region of 6 ..mu..m RMS (14 ..mu..m FWHM). The performance with argon, krypton or xenon at pressures from 1 to 10 atm is explored for the x-ray energy range 5 to 25 keV. At a resolution of 6 ..mu..m RMS the effects of photoelectron and Auger electron range, electronic noise, avalanche spread, lateral electron diffusion, as well as x-ray beam collimation, become of comparable magnitude. Their limiting effects o… more
Date: April 1, 1986
Creator: Fischer, J.; Radeka, V. & Smith, G.C.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

UV photoemission from metal cathodes for picosecond power switches

Description: Results are reported of photoemission studies using laser pulses of 10 ps duration and 4.66 eV photon energy on metal cathodes. These included thin wires, flat surfaces and an yttrium cathode with a grainy surface. The measurements of current density and quantum efficiency under low and high surface fields indicate that field assisted efficiencies exceeding 0.1% and current densities exceeding 10/sup 5/ A/cm/sup 2/ are obtainable. The results are compared to the requirements of switch power app… more
Date: January 1, 1989
Creator: Fischer, J.; Srinivasan-RAo, T. & Tsang, T.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
Back to Top of Screen