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1/m<sub>c</sub> Terms in lambda<sup>+</sup><sub>c</sub> Semileptonic Decays (open access)

1/m<sub>c</sub> Terms in lambda<sup>+</sup><sub>c</sub> Semileptonic Decays

We use the heavy quark effective theory to investigate the form factors that describe the semileptonic decays lambda<sup>+</sup><sub>c</sub> -> lambda e<sup>+</sup> nu, to order 1/m<sub>c</sub>. We find that a total of four form factors are needed to this order, in contrast with two form factors to leading order, and six form factors in the most general case. We point out some relationships that arise among the general form factors.
Date: February 1, 1992
Creator: Roberts, Winston
Object Type: Article
System: The UNT Digital Library
A 2 to 4 nm high power FEL on the SLAC linac (open access)

A 2 to 4 nm high power FEL on the SLAC linac

We report the results of preliminary studies of a 2 to 4 nm SASE FEL, using a photoinjector to produce the electron beam, and the SLAC linac to accelerate it to an energy up to 10 GeV. Longitudinal bunch compression is used to increases ten fold the peak current to 2.5 kA, while reducing the bunch length to the subpicosecond range. The saturated output power is in the multi-gigawatt range, producing about 10{sup 14} coherent photons within a bandwidth of about 0.2% rms, in a pulse of several millijoules. At 120Hz repetition rate the average power is about 1 W. The system is optimized for x-ray microscopy in the water window around 2 to 4 nm, and will permit imaging a biological sample in a single subpicosecond pulse.
Date: September 1, 1992
Creator: Pellegrini, C.; Rosenzweig, J.; Nuhn, H. D.; Pianetta, P.; Tatchyn, R.; Winick, H. et al.
Object Type: Article
System: The UNT Digital Library
3-D Field Computations for Accelerator Magnets Using Finite Element and Integral Codes (open access)

3-D Field Computations for Accelerator Magnets Using Finite Element and Integral Codes

Two dimensional (2-D) computation has been an accepted part of the design of accelerator magnets since the 1960's, but three-dimensional (3-D) computations are still not fully trusted. This paper describes the successes and limitations of 3-D computations, as applied to accelerator magnets for the Advanced Photon Source (APS) at Argonne National Laboratory (ANL). Both the finite element code TOSCA and the edge element volume integral code CORAL have been used in these computations. The ends of the dipole bending magnet for the injector synchrotron were designed using TOSCA; comparisons with measurements are described. Computation of other APS magnets are also described.
Date: 1992~
Creator: Turner, L. R.; Kim, S. H.; Kim, K. & Kettunen, L.
Object Type: Article
System: The UNT Digital Library
3-D field computations for accelerator magnets using finite element and integral codes (open access)

3-D field computations for accelerator magnets using finite element and integral codes

Two dimensional (2-D) computation has been an accepted part of the design of accelerator magnets since the 1960`s, but three-dimensional (3-D) computations are still not fully trusted. This paper describes the successes and limitations of 3-D computations, as applied to accelerator magnets for the Advanced Photon Source (APS) at Argonne National Laboratory (ANL). Both the finite element code TOSCA and the edge element volume integral code CORAL have been used in these computations. The ends of the dipole bending magnet for the injector synchrotron were designed using TOSCA; comparisons with measurements are described. Computation of other APS magnets are also described.
Date: December 1, 1992
Creator: Turner, L. R.; Kim, S. H.; Kim, K. & Kettunen, L.
Object Type: Article
System: The UNT Digital Library
3-D numerical investigation of the mantle dynamics associated with the breakup of Pangea (open access)

3-D numerical investigation of the mantle dynamics associated with the breakup of Pangea

Three-dimensional finite element calculations in spherical geometry are performed to study the response of the mantle with platelike blocks at its surface to an initial condition corresponding to subduction along the margins of Pangea. The mantle is treated as an infinite Prandtl number Boussinesq fluid inside a spherical shell with isothermal, undeformable, free-slip boundaries. Nonsubducting rigid blocks to model continental lithosphere are included in the topmost layer of the computational mesh. At the beginning of the numerical experiments these blocks represent the present continents mapped to their approximate Pangean positions. Asymmetrical downwelling at the margins of these nonsubducting blocks results in a pattern of stresses that acts to pull the supercontinent apart. The calculations suggest that the breakup of Pangea and the subsequent global pattern of seafloor spreading was driven largely by the subduction at the Pangean margins.
Date: January 1, 1992
Creator: Baumgardner, J. R.
Object Type: Article
System: The UNT Digital Library
3-D numerical investigation of the mantle dynamics associated with the breakup of Pangea (open access)

3-D numerical investigation of the mantle dynamics associated with the breakup of Pangea

Three-dimensional finite element calculations in spherical geometry are performed to study the response of the mantle with platelike blocks at its surface to an initial condition corresponding to subduction along the margins of Pangea. The mantle is treated as an infinite Prandtl number Boussinesq fluid inside a spherical shell with isothermal, undeformable, free-slip boundaries. Nonsubducting rigid blocks to model continental lithosphere are included in the topmost layer of the computational mesh. At the beginning of the numerical experiments these blocks represent the present continents mapped to their approximate Pangean positions. Asymmetrical downwelling at the margins of these nonsubducting blocks results in a pattern of stresses that acts to pull the supercontinent apart. The calculations suggest that the breakup of Pangea and the subsequent global pattern of seafloor spreading was driven largely by the subduction at the Pangean margins.
Date: October 1, 1992
Creator: Baumgardner, J. R.
Object Type: Article
System: The UNT Digital Library
7-GeV Advanced Photon Source Instrumentation Initiative. Conceptual Design Report (open access)

7-GeV Advanced Photon Source Instrumentation Initiative. Conceptual Design Report

In this APS Instrumentation Initiative, 2.5-m-long and 5-m-long insertion-device x-ray sources will be built on 9 straight sections of the APS storage ring, and an additional 9 bending-magnet sources will also be put in use. The front ends for these 18 x-ray sources will be built to contain and safeguard access to these bright x-ray beams. In addition, funds will be provided to build state-of-the-art insertion-device beamlines to meet scientific and technological research demands well into the next century. This new initiative will also include four user laboratory modules and a special laboratory designed to meet the x-ray imaging research needs of the users. The Conceptual Design Report (CDR) for the APS Instrumentation Initiative describes the scope of all the above technical and conventional construction and provides a detailed cost and schedule for these activities. According to these plans, this new initiative begins in FY 1994 and ends in FY 1998. The document also describes the preconstruction R & D plans for the Instrumentation Initiative activities and provides the cost estimates for the required R & D.
Date: October 1992
Creator: Argonne National Laboratory
Object Type: Report
System: The UNT Digital Library
7-GeV Advanced Photon Source Instrumentation Initiative conceptual design report (open access)

7-GeV Advanced Photon Source Instrumentation Initiative conceptual design report

In this APS Instrumentation Initiative, 2.5-m-long and 5-m-long insertion-device x-ray sources will be built on 9 straight sections of the APS storage ring, and an additional 9 bending-magnet sources will also be put in use. The front ends for these 18 x-ray sources will be built to contain and safeguard access to these bright x-ray beams. In addition, funds will be provided to build state-of-the-art insertion-device beamlines to meet scientific and technological research demands well into the next century. This new initiative will also include four user laboratory modules and a special laboratory designed to meet the x-ray imaging research needs of the users. The Conceptual Design Report (CDR) for the APS Instrumentation Initiative describes the scope of all the above technical and conventional construction and provides a detailed cost and schedule for these activities. According to these plans, this new initiative begins in FY 1994 and ends in FY 1998. The document also describes the preconstruction R&D plans for the Instrumentation Initiative activities and provides the cost estimates for the required R&D.
Date: December 1992
Creator: unknown
Object Type: Report
System: The UNT Digital Library
7-GeV Advanced Photon Source Instrumentation Initiative conceptual design report (open access)

7-GeV Advanced Photon Source Instrumentation Initiative conceptual design report

In this APS Instrumentation Initiative, 2.5-m-long and 5-m-long insertion-device x-ray sources will be built on 9 straight sections of the APS storage ring, and an additional 9 bending-magnet sources will also be put in use. The front ends for these 18 x-ray sources will be built to contain and safeguard access to these bright x-ray beams. In addition, funds will be provided to build state-of-the-art insertion-device beamlines to meet scientific and technological research demands well into the next century. This new initiative will also include four user laboratory modules and a special laboratory designed to meet the x-ray imaging research needs of the users. The Conceptual Design Report (CDR) for the APS Instrumentation Initiative describes the scope of all the above technical and conventional construction and provides a detailed cost and schedule for these activities. According to these plans, this new initiative begins in FY 1994 and ends in FY 1998. The document also describes the preconstruction R D plans for the Instrumentation Initiative activities and provides the cost estimates for the required R D.
Date: December 1, 1992
Creator: unknown
Object Type: Report
System: The UNT Digital Library
9-1-1 Caller, Volume 4, Number 1, January/February 1992 (open access)

9-1-1 Caller, Volume 4, Number 1, January/February 1992

Bimonthly newsletter of the Texas Advisory Commission on State Emergency Communications discussing news and activities of the organization as well as other information related to 9-1-1 services and other emergency communication within Texas.
Date: January 1992
Creator: Texas. Advisory Commission on State Emergency Communications.
Object Type: Journal/Magazine/Newsletter
System: The Portal to Texas History
9-1-1 Caller, Volume 4, Number 2, March/April 1992 (open access)

9-1-1 Caller, Volume 4, Number 2, March/April 1992

Bimonthly newsletter of the Texas Advisory Commission on State Emergency Communications discussing news and activities of the organization as well as other information related to 9-1-1 services and other emergency communication within Texas.
Date: March 1992
Creator: Texas. Advisory Commission on State Emergency Communications.
Object Type: Journal/Magazine/Newsletter
System: The Portal to Texas History
9-1-1 Caller, Volume 4, Number 3, May/June 1992 (open access)

9-1-1 Caller, Volume 4, Number 3, May/June 1992

Bimonthly newsletter of the Texas Advisory Commission on State Emergency Communications discussing news and activities of the organization as well as other information related to 9-1-1 services and other emergency communication within Texas.
Date: May 1992
Creator: Texas. Advisory Commission on State Emergency Communications.
Object Type: Journal/Magazine/Newsletter
System: The Portal to Texas History
9-1-1 Caller, Volume 4, Number 4, August/September 1992 (open access)

9-1-1 Caller, Volume 4, Number 4, August/September 1992

Bimonthly newsletter of the Texas Advisory Commission on State Emergency Communications discussing news and activities of the organization as well as other information related to 9-1-1 services and other emergency communication within Texas.
Date: August 1992
Creator: Texas. Advisory Commission on State Emergency Communications.
Object Type: Journal/Magazine/Newsletter
System: The Portal to Texas History
9-1-1 Caller, Volume 4, Number 5, October/November 1992 (open access)

9-1-1 Caller, Volume 4, Number 5, October/November 1992

Bimonthly newsletter of the Texas Advisory Commission on State Emergency Communications discussing news and activities of the organization as well as other information related to 9-1-1 services and other emergency communication within Texas.
Date: October 1992
Creator: Texas. Advisory Commission on State Emergency Communications.
Object Type: Journal/Magazine/Newsletter
System: The Portal to Texas History
9-{beta}-arabinofuranosyladenine preferentially sensitizes radioresistant squamous cell carcinoma cell lines to x-rays (open access)

9-{beta}-arabinofuranosyladenine preferentially sensitizes radioresistant squamous cell carcinoma cell lines to x-rays

The effect of 9-{beta}-arabinofuranosyladenine (ara-A) on sensitivity to the deleterious effects of x-rays was studied in six squamous cell carcinoma cell lines. Three lines were relatively radioresistant, having D{sub 0} values of 2.31 to 2.89 Gy, and the other three lines were relatively radiosensitive, having D{sub 0} values of between 1.07 and 1.45 Gy. Ara-A (50 or 500 {mu}M) was added to cultures 30 min prior to irradiation and removed 30 min after irradiation, and sensitivity was measured in terms of cell survival. The radiosensitizing effect of ara-A was very dependent on the inherent radiosensitivity of the tumor cell line. Fifty micromolar concentrations of ara-A sensitized only the two most radioresistant lines, SCC-12B.2 and JSQ-3. Five hundred micromolar concentrations of ara-A sensitized the more sensitive cell lines, SQ-20B and SQ-9G, but failed to have any effect on the radiation response of the two most sensitive cell lines, SQ-38 and SCC-61. Concentrations of ara-A as low as 10 {mu}M were equally efficient in inhibiting DNA synthesis in all six cell lines. These results suggest that the target for the radiosensitizing effect of ara-A is probably related to the factor controlling the inherent radiosensitivity of human tumor cells. Therefore, ara-A might be …
Date: June 1, 1992
Creator: Heaton, D.; Mustafi, R. & Schwartz, J. L.
Object Type: Report
System: The UNT Digital Library
The 17 keV neutrino and neutrino tagging (open access)

The 17 keV neutrino and neutrino tagging

P-788 at FNAL proposed to search for neutrino oscillations in a tagged neutrino line. A K{sub L} beam and the decay modes K{sub L} {yields} {pi}{mu}{nu}{sub {mu}} and K {sub L} {yields} {pi}e{nu}{sub e} provides the neutrino flux. An upstream tagging spectrometer then identifies the hadron and lepton and reconstructs the K{sub L} decay; the lepton identification will specifies the neutrino as {nu}{sub e} or {nu}{sub {mu}} and distinguishes {nu} from {bar {nu}} at the decay vertex. A neutrino detector modeled after an existing deep-inelastic scattering spectrometer (rates have been worked out for the CCFR apparatus) can be used to associate the K{sub L} with a neutrino interaction, measure the neutrino energy, and analyze outgoing muons. Monte Carlo studies show that 30K {nu}{sub e} and 20K {nu}{sub {mu}} could be obtained in two fixed target runs at the Tevatron.
Date: February 1, 1992
Creator: Bernstein, R.H.
Object Type: Article
System: The UNT Digital Library
The 17 keV neutrino and neutrino tagging (open access)

The 17 keV neutrino and neutrino tagging

P-788 at FNAL proposed to search for neutrino oscillations in a tagged neutrino line. A K{sub L} beam and the decay modes K{sub L} {yields} {pi}{mu}{nu}{sub {mu}} and K {sub L} {yields} {pi}e{nu}{sub e} provides the neutrino flux. An upstream tagging spectrometer then identifies the hadron and lepton and reconstructs the K{sub L} decay; the lepton identification will specifies the neutrino as {nu}{sub e} or {nu}{sub {mu}} and distinguishes {nu} from {bar {nu}} at the decay vertex. A neutrino detector modeled after an existing deep-inelastic scattering spectrometer (rates have been worked out for the CCFR apparatus) can be used to associate the K{sub L} with a neutrino interaction, measure the neutrino energy, and analyze outgoing muons. Monte Carlo studies show that 30K {nu}{sub e} and 20K {nu}{sub {mu}} could be obtained in two fixed target runs at the Tevatron.
Date: February 1, 1992
Creator: Bernstein, R. H.
Object Type: Article
System: The UNT Digital Library
A 50 mm bore superconducting dipole with a unique iron yoke structure (open access)

A 50 mm bore superconducting dipole with a unique iron yoke structure

A 50 mm bore superconducting dipole with a thin stainless steel collar and a close in elliptical iron yoke was designed in order to obtain a high transfer function SW low saturation effects on the multipoles, and a one meter model was built and tested. Training behavior of the first 1 m model, called D19, is presented at 4.3 K and 1.8 K. At 1.8 K it reached the record field of 10.06 T. The two layer cos [theta] winding uses 30 and 36 strand cables identical to the cables of the 50 mm bore SSC dipole and it has an operating field of 6.6 T at 4.35 K with a current of 5800 A. To evaluate behavior at high fields, the mechanical structure for the model was designed for 10 T. The thin collar itself provides only a minimum prestress of 10 MPa. and the full prestress of 70 MPa is given by the iron yoke. An aluminum spacer is used to control the gap size in the vertically split iron yoke. The tapered gap in the yoke is determined by the size of the Al spacer so that during cooldown there is no loss of coil prestress and …
Date: August 1, 1992
Creator: Dell'Orco, D.; Caspi, S.; O'Neill, J.; Lietzke, A.; Scanlan, R.; Taylor, C. E. et al.
Object Type: Article
System: The UNT Digital Library
A 50 mm bore superconducting dipole with a unique iron yoke structure (open access)

A 50 mm bore superconducting dipole with a unique iron yoke structure

A 50 mm bore superconducting dipole with a thin stainless steel collar and a close in elliptical iron yoke was designed in order to obtain a high transfer function SW low saturation effects on the multipoles, and a one meter model was built and tested. Training behavior of the first 1 m model, called D19, is presented at 4.3 K and 1.8 K. At 1.8 K it reached the record field of 10.06 T. The two layer cos {theta} winding uses 30 and 36 strand cables identical to the cables of the 50 mm bore SSC dipole and it has an operating field of 6.6 T at 4.35 K with a current of 5800 A. To evaluate behavior at high fields, the mechanical structure for the model was designed for 10 T. The thin collar itself provides only a minimum prestress of 10 MPa. and the full prestress of 70 MPa is given by the iron yoke. An aluminum spacer is used to control the gap size in the vertically split iron yoke. The tapered gap in the yoke is determined by the size of the Al spacer so that during cooldown there is no loss of coil prestress and …
Date: August 1, 1992
Creator: Dell`Orco, D.; Caspi, S.; O`Neill, J.; Lietzke, A.; Scanlan, R.; Taylor, C. E. et al.
Object Type: Article
System: The UNT Digital Library
100 MeV laser accelerator demonstration and 1 GeV baseline design development. 1992 Annual report (open access)

100 MeV laser accelerator demonstration and 1 GeV baseline design development. 1992 Annual report

The acceleration of relativistic electrons using the inverse Cerenkov effect was first demonstrated at Stanford University in 1981. Later, Fontana and Pantell developed an improved configuration for the inverse Cerenkov acceleration (ICA) process. A radially polarized laser beam is focused by an axicon onto the e-beam traveling through a gas-filled interaction region. The light intersects the e-beam at the Cerenkov angle {theta}{sub c}, where {theta}{sub c} = cos{sup {minus}1}(1/n{beta}), n is the index of refraction of the gas, and {beta} is the ratio of the electron velocity to the speed of light. The goal of the present program is to demonstrate improved laser acceleration using the Fontana and Pantell configuration. The experiments will be performed on the Accelerator Test Facility (ATF) located at Brookhaven National Laboratory (BNL). This facility features a 50 MeV linac fed by a Nd:YAG (4{omega}) laser-driven photocathode e-gun. It will be upgraded to 65 MeV in the near future. The ATF also has a high peak power CO{sub 2} laser, which was developed for laser acceleration studies. The present ICA experiment was divided into two phases. Phase 1 was to examine certain experimental issues in preparation for Phase 2. Phase 1 was successfully completed in the …
Date: December 1, 1992
Creator: unknown
Object Type: Report
System: The UNT Digital Library
101-SY Hydrogen Safety Project chemical analysis support: Window ``C`` total organic carbon analysis (open access)

101-SY Hydrogen Safety Project chemical analysis support: Window ``C`` total organic carbon analysis

Core samples taken from Hanford double-shell waste tank 101-SY during Window ``C`` (after the May 1991 gas release event) were analyzed for total organic carbon by the staff of the Analytical Chemistry Laboratory at Pacific Northwest Laboratory. The procedure uses the oxidation/extraction method of hot acid persulfate oxidation. Evolved CO{sub 2} is measured by a UIC Coulometric Carbon Analyzer coulometry detector. Samples are acidified with heated sulfuric acid to drive off all inorganic carbonate carbon as CO{sub 2}. Excess potassium persulfate oxidant, along with a silver catalyst, is then added to the heated sulfuric acid solution. All organic carbon is oxidized to CO{sub 2}, swept away by the carrier gas to the Coulometrics Analyzer, and the results calculated and displayed directly as {mu}g carbon titrated.
Date: January 1, 1992
Creator: Gillespie, B. M.; Stromatt, R. W.; Baldwin, D. L. & Hoopes, F. V.
Object Type: Report
System: The UNT Digital Library
101-SY Hydrogen Safety Project chemical analysis support: Window C'' total organic carbon analysis (open access)

101-SY Hydrogen Safety Project chemical analysis support: Window C'' total organic carbon analysis

Core samples taken from Hanford double-shell waste tank 101-SY during Window C'' (after the May 1991 gas release event) were analyzed for total organic carbon by the staff of the Analytical Chemistry Laboratory at Pacific Northwest Laboratory. The procedure uses the oxidation/extraction method of hot acid persulfate oxidation. Evolved CO{sub 2} is measured by a UIC Coulometric Carbon Analyzer coulometry detector. Samples are acidified with heated sulfuric acid to drive off all inorganic carbonate carbon as CO{sub 2}. Excess potassium persulfate oxidant, along with a silver catalyst, is then added to the heated sulfuric acid solution. All organic carbon is oxidized to CO{sub 2}, swept away by the carrier gas to the Coulometrics Analyzer, and the results calculated and displayed directly as {mu}g carbon titrated.
Date: January 1, 1992
Creator: Gillespie, B. M.; Stromatt, R. W.; Baldwin, D. L. & Hoopes, F. V.
Object Type: Report
System: The UNT Digital Library
The 400 MeV Linac Upgrade at Fermilab (open access)

The 400 MeV Linac Upgrade at Fermilab

The Fermilab Linac Upgrade in planned to increase the energy of the H[sup [minus]] linac from 200 to 400 MeV. This is intended to reduce the incoherent space-charge tuneshift at injection into the 8 GeV Booster which limit either the brightness or the total intensity of the beam. The Linac Upgrade will be achieved by replacing the last four 201.25 MHs drift-tube linac (DTL) tanks which accelerate the beam from 116 to 200 MeV, with seven 805 MRs side-coupled cavity modules operating at an average axial field of about 7.5 MV/meter. This will allow acceleration to 400 MeV in the existing Linac enclosure. Each accelerator module will be driven with a 12 MW klystron-based rf power supply. Three of seven accelerator modules have been fabricated, power tested and installed in their temporary location adjacent to the existing DTL. All seven RF Modulators have been completed and klystron installation has begun. Waveguide runs have completed from the power supply gallery to the accelerator modules. The new linac will be powered in the temporary position without beam in order to verify overall system reliability until the laboratory operating schedule permits final conversion to 400 MeV operation.
Date: December 1, 1992
Creator: Noble, R.J.
Object Type: Article
System: The UNT Digital Library
The 400 MeV Linac Upgrade at Fermilab (open access)

The 400 MeV Linac Upgrade at Fermilab

The Fermilab Linac Upgrade in planned to increase the energy of the H{sup {minus}} linac from 200 to 400 MeV. This is intended to reduce the incoherent space-charge tuneshift at injection into the 8 GeV Booster which limit either the brightness or the total intensity of the beam. The Linac Upgrade will be achieved by replacing the last four 201.25 MHs drift-tube linac (DTL) tanks which accelerate the beam from 116 to 200 MeV, with seven 805 MRs side-coupled cavity modules operating at an average axial field of about 7.5 MV/meter. This will allow acceleration to 400 MeV in the existing Linac enclosure. Each accelerator module will be driven with a 12 MW klystron-based rf power supply. Three of seven accelerator modules have been fabricated, power tested and installed in their temporary location adjacent to the existing DTL. All seven RF Modulators have been completed and klystron installation has begun. Waveguide runs have completed from the power supply gallery to the accelerator modules. The new linac will be powered in the temporary position without beam in order to verify overall system reliability until the laboratory operating schedule permits final conversion to 400 MeV operation.
Date: December 1992
Creator: Noble, Robert J.
Object Type: Article
System: The UNT Digital Library