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Development of thin foils for use in generating neutral particle beams (open access)

Development of thin foils for use in generating neutral particle beams

The Isotope Research Materials Laboratory (IRML) was requested to prepare large-area, ultrathin aluminum and carbon foils for use in beam neutralization experiments. There were two major parts to this request. The first was to immediately provide a number of 5-cm-dia foils 5 to 20 ..mu..g/cm/sup 2/ thick for use in experiments at the Fusion Materials Irradiation Test (FMIT) facility and at Argonne National Laboratory (ANL). The second, longer-term request was to develop methods to prepare 25-cm x 25-cm, 10-..mu..g/cm/sup 2/ aluminum neutralizer foils. Both parts of the request have been successfully met.
Date: January 1, 1986
Creator: Aaron, W. S.; Zevenbergen, L. A.; Adair, H. L.; Culpepper, C. A.; McCulla, W. H.; Nolan, T. A. et al.
System: The UNT Digital Library
Preparation of thin films for use in generating neutral particle beams (open access)

Preparation of thin films for use in generating neutral particle beams

Large-area, thin aluminum foils were prepared for use in beam neutralization experiments. The foils were made using either electron beams of resistance heating. Foil thickness and uniformity were determined using alpha particles. The foils perform very well when bombarded by energetic H/sup -/ ions. (DLC)
Date: January 1, 1986
Creator: Aaron, W.S.; Zevenbergen, L.A. & Adair, H.L.
System: The UNT Digital Library
Limit on tau neutrino mass (open access)

Limit on tau neutrino mass

Using the complete data sample of 300 pb/sup -1/ collected by the HRS spectrometer in e/sup +/e/sup -/ collisions at 29 GeV, mass limit for the tau neutrino is set. The end point of the hadronic mass spectrum is determined in the decays tau ..-->.. 5..pi../sup + -/nu/sub tau/ and tau ..-->.. 5..pi../sup + -/..pi../sup 0/nu/sub tau/. At 95% confidence level, an upper limit of M/sub nu/sub tau// < 76 MeV/c/sup 2/, is found. 8 refs., 4 figs.
Date: January 1, 1986
Creator: Abachi, S.; Akerlof, C.; Baringer, P.; Beltrami, I.; Blockus, D.; Bonvicini, G. et al.
System: The UNT Digital Library
Charm D production in e/sup +/e/sup -/ annihilation at 29 GeV (open access)

Charm D production in e/sup +/e/sup -/ annihilation at 29 GeV

Results are presented on the analysis of charm D Production from 300 pb/sup -1/ of data taken with the HRS Detector at PEP. The electroweak asymmetry is -8.4 +- 3.6% and R (D + D*) = 1.57 +- 0.17. Fragmentation functions for D/sup 0/, D/sup +/, D*/sup +/ production and the results of a search for the D** are given. 10 refs., 9 figs.
Date: January 1, 1986
Creator: Abachi, S.; Akerlof, C.; Baringer, P.; Blockus, D.; Brabson, B.; Brom, J. M. et al.
System: The UNT Digital Library
Limit on tau decay to 7-charged tracks (open access)

Limit on tau decay to 7-charged tracks

Using the complete data sample of 300 pb/sup -1/ from e/sup +/e/sup -/ collisions at 29 GeV, the HRS collaboration has searched for tau decay to 7 charged particles and any number of neutrals. No events were found. The corresponding upper limit to the branching ratio is B(tau ..-->.. 7..pi../sup + -/ + n..gamma.. + nu/sub tau/) < 3.8 x 10/sup -4/ at 90% confidence level. Using the final HRS data sample we also report updated branching ratios for tau ..-->.. 5..pi../sup + -/ + nu/sub tau/ and tau ..-->.. 5..pi../sup + -/ + ..pi../sup 0/ + nu/sub tau/.
Date: January 1, 1986
Creator: Abachi, S.; Akerlof, C.; Baringer, P.; Blockus, D.; Brabson, B.; Brom, J. M. et al.
System: The UNT Digital Library
Measurement of the D/sup 0/ meson lifetime (open access)

Measurement of the D/sup 0/ meson lifetime

We report the measurement of the lifetime of the D/sup 0/ meson. The direct observation of the decay vertex distribution in the process D/sup 0/ ..-->.. K/sup -/..pi../sup +/ was made using a vertex chamber installed in the HRS detector at PEP. The measured lifetime is found to be tau/sub D/sup 0// = .42 +- .09 +- .06ps. 5 refs., 4 figs.
Date: January 1, 1986
Creator: Abachi, S.; Akerlof, C.; Baringer, P.; Blockus, D.; Brabson, B.; Brom, J. M. et al.
System: The UNT Digital Library
Measurement of the electroweak asymmetry in the reaction e/sup +/e/sup -/. -->. tau/sup +/tau/sup -/ at 29 GeV (open access)

Measurement of the electroweak asymmetry in the reaction e/sup +/e/sup -/. -->. tau/sup +/tau/sup -/ at 29 GeV

This paper reports the electroweak asymmetry in the reaction e/sup +/e/sup -/ ..-->.. tau/sup +/tau/sup -/ at 29 GeV. The results came from data taken with the High Resolution Spectrometer at PEP corresponding to an integrated luminosity of 256 pb/sup -1/. The 7372 observed events give A/sub tau tau/ = -(4.4 +- 1.4 +- 0.5)%. Events selected in the central region of the detector measure a total cross section of R/sub tau tau/ = 1.06 +- 0.02 +- 0.04. 5 refs., 1 fig.
Date: June 1, 1986
Creator: Abachi, S.; Akerlof, C.; Baringer, P.; Blockus, D.; Brabson, B.; Brom, J. M. et al.
System: The UNT Digital Library
Multiplicity distributions in e/sup +/e/sup -/ annihilation at 29 GeV: a comparison with hadronic data (open access)

Multiplicity distributions in e/sup +/e/sup -/ annihilation at 29 GeV: a comparison with hadronic data

The charged particle multiplicity distributions for single jets in e/sup +/e/sup -/ annihilation at 29 GeV have been measured using the High Resolution Spectrometer at PEP. The shape of the distribution agrees well with a Poisson distribution. No correlation is observed between the multiplicities in the two jets of an event. For fixed values of the prong number of the total event, the multiplicity sharing between the two jets is in good agreement with a binomial distribution. These observations are contrasted to the results from soft hadronic collisions and conclusions are drawn about the nature of clusters. 21 refs., 4 figs.
Date: June 1, 1986
Creator: Abachi, S.; Akerlof, C.; Baringer, P.; Blockus, D.; Brabson, B.; Brom, J. M. et al.
System: The UNT Digital Library
lambda. production in e/sup +/e/sup -/ annihilations at 29 GeV (open access)

lambda. production in e/sup +/e/sup -/ annihilations at 29 GeV

This paper presents measurements of the inclusive production cross sections of ..lambda.. baryons in e/sup +/e/sup -/ annihilations at ..sqrt..s = 29 GeV. The data sample corresponds to an integrated luminosity of 256 pb/sup -1/ collected with the High Resolution Spectrometer at PEP. Comparisons are made to the predictions of the Lund model. The data are well described using a strange diquark suppression parameter, (us/ud)/(s/d), of 0.89 +- 0.10/sub -0.16//sup +0.56/, and the measured ..lambda../sub c/ ..-->.. ..lambda.. + X branching ratio of 23 +- 10%. No polarization is observed in the ..lambda.. decays. 17 refs., 5 figs.
Date: May 1, 1986
Creator: Abachi, S.; Baringer, P.; Beltrami, I.; Bylsma, B.G.; DeBonte, R.; Koltick, D. et al.
System: The UNT Digital Library
Observation of tensor and scalar mesons produced in e/sup +/e/sup -/ annihilation at 29 GeV (open access)

Observation of tensor and scalar mesons produced in e/sup +/e/sup -/ annihilation at 29 GeV

The production of the tensor mesons, integral/sup 0/(1270) and K*/sup 0/(1430), and the scalar meson S(975) have been observed in e/sup +/e/sup -/ annihilation at 29 GeV center of mass energy, using data obtained with the HRS detector at the PEP storage ring. The mean multiplicities for meson momenta greater than 1450 MeV/c are <n/sub f/sup 0//> = 0.11 +- 0.04, <n/sub K*/sup 0/(1430)/> = 0.10 +- 0.06, and <n/sub S/> = 0.05 +- 0.02 per hadronic event. The fragmentation functions of the tensor mesons are in good agreement with the predictions of the Webber cluster model. The possibility of a large strange quark component in the S meson structure is suggested by the data.
Date: January 1, 1986
Creator: Abachi, S.; Baringer, P.; Bylsma, B. G.; DeBonte, R.; Koltick, D.; Loeffler, F. J. et al.
System: The UNT Digital Library
Physical inventory verification exercise for a highly enriched uranium fabrication facility (open access)

Physical inventory verification exercise for a highly enriched uranium fabrication facility

The International Atomic Energy Agency, in collaboration with the US Support Program (POTAS), has developed and conducted a training exercise simulating a physical inventory verification (PIV) at a highly enriched uranium (HEU) fabrication facility. This exercise is part of a series sponsored by the POTAS program, including PIVs at light-water reactors and plutonium fabrication facilities. The first HEU exercise took place in September 1985 at Los Alamos National Laboratory and a second is scheduled for Spring, 1987 at JRC, ISPRA. The main objectives of these exercises are: to provide the opportunity for inspectors to test and evaluate the use of nondestructive assay (NDA) equipment and computer software under conditions similar to those found during actual inspections; to use the data generated to evaluate different inspection procedures and strategies; and to exchange ideas on PIV procedures between the three operations divisions. Because the exercises are conducted in a neutral environment, free of the time pressure often found in actual inspections, it is possible for the inspectors to achieve the course objectives.
Date: January 1, 1986
Creator: Abedin-Zadeh, R. & Augustson, R.H.
System: The UNT Digital Library
Technology development for the design of shallow land burial facilities at semiarid sites (open access)

Technology development for the design of shallow land burial facilities at semiarid sites

The following topics are discussed: effectiveness of a moisture barrier, physical basis for capillary barriers, trench cap designs for long-term stabilization, biointrusion barrier testing, and joint DOE/NRC tracer migration experiment. (LM)
Date: January 1, 1986
Creator: Abeele, W. V.; Nyhan, J. W. & Drennon, B. J.
System: The UNT Digital Library
Exchange of bonded hydrogen in amorphous silicon by deuterium (open access)

Exchange of bonded hydrogen in amorphous silicon by deuterium

We show that bonded hydrogen in a-Si:H is readily exchanged by atomic deuterium when exposed to a deuterium plasma discharge. The effective diffusion coefficient for the D,H exchange 10/sup -14/ cm/sup 2//sec at 160/sup 0/C, is comparable to that of interstitial hydrogen in c-Si.
Date: December 1, 1986
Creator: Abeles, B.; Yang, L.; Leta, D.P. & Majkrzak, C.F.
System: The UNT Digital Library
NMR investigations of aging effects in palladium tritide (open access)

NMR investigations of aging effects in palladium tritide

Using pulsed NMR techniques, relaxation times for triton, proton, and /sup 3/He nuclei in recently synthesized PdH/sub x/ and PdT/sub x/ samples were measured as a function of temperature in the range 100 less than or equal to T less than or equal to 300/sup 0/K. Rigid lattice second moments (T approx. = 100/sup 0/K) were also determined. These results provide baseline information for an extended study of aging effects of PdT/sub x/. 6 refs., 7 figs., 2 tabs.
Date: January 1, 1986
Creator: Abell, G.C. & Attalla, A.
System: The UNT Digital Library
Influence of moisture on the behavior of aerosols (open access)

Influence of moisture on the behavior of aerosols

The behavior of aerosols assumed to be characteristic of those generated during light water reactor (LWR) accident sequences and released into containment has been studied in the Nuclear Safety Pilot Plant (NSPP) located at the Oak Ridge National Laboratory (ORNL). It has been observed that in a saturated steam-air environment a change occurs in the shape of aerosol agglomerates of U/sub 3/O/sub 8/ aerosol, Fe/sub 2/O/sub 3/ aerosol, and mixed U/sub 3/O/sub 8/-Fe/sub 2/O/sub 3/ aerosol from branched-chain to spherical, and that the rate of reduction in the airborne aerosol mass concentration is increased relative to the rate observed in a dry atmosphere. The effect of a steam-air environment on the behavior of concrete aerosol is different. The shape of the agglomerated concrete aerosol is intermediate between branched-chain and spherical and the effect on the rate of reduction in airborne mass concentration appears to be slight. In a related project the shape of an agglomerated Fe/sub 2/O/sub 3/ aerosol was observed to change from branched-chain to spherical at, or near, 100% relative humidity.
Date: January 1, 1986
Creator: Adams, R. E.; Longest, A. W. & Tobias, M. L.
System: The UNT Digital Library
Criteria for the selection of nuclides for radioimmunotherapy (open access)

Criteria for the selection of nuclides for radioimmunotherapy

This report describes many factors that need to be considered if radioimmunotherapy is to become a commonplace reality. For beta-emitting radionuclides, two physical features of importance are half-life and energy, with the latter determining the range. These features must be matched to the pharmacokinetics of the carrier and the distribution of the radionuclide, both macroscopically and microscopically. Alpha-particle emitters could be considered for cells that are readily accessible to the labeled antibody and for populations that uniformly and constantly display the targeted antigen or idiotype, e.g., trafficking cells such as T or B lymphocytes. For cells that concentrate the radioactive label, the use of low-energy electrons should be examined. If the radionuclide is translocated to the nucleus, the Auger effect can be particularly lethal because of the high LET-like biological response. 15 refs., 3 figs., 2 tabs.
Date: January 1, 1986
Creator: Adelstein, S. J. & Kassis, A. I.
System: The UNT Digital Library
Test beam results for silicon microstrip detectors with VLSI read-out (open access)

Test beam results for silicon microstrip detectors with VLSI read-out

A telescope consisting of three silicon microstrip detectors has been tested in a high energy positron beam at SLAC. Each detector has trips with 25 micron pitch and is read out by two 128-channel NMOS integrated circuits (''Microplex''). Results on the signal-to-noise ratio, spatial resolution, and two-track separation are given.
Date: April 1, 1986
Creator: Adolphsen, C.; Litke, A.; Schwarz, A.; Turala, M.; Lueth, V.; Breakstone, A. et al.
System: The UNT Digital Library
New solution of the problem of EMP coupling on cables over ground of finite conductivity (open access)

New solution of the problem of EMP coupling on cables over ground of finite conductivity

This new solution replaces Dawson's Integral, in the old solution, by an infinite series. For typical EMP parameters, the solution is approximated by a double exponential function whose numerical constants are derived. Both forms of the new solution ae convenient for the calculation of the transient.
Date: January 1, 1986
Creator: Agouridis, D.C.
System: The UNT Digital Library
Polarized Proton Acceleration at the Brookhaven AGS (open access)

Polarized Proton Acceleration at the Brookhaven AGS

At the conclusion of polarized proton commissioning in February 1986, protons with an average polarization of 45%, momentum of 21.7 GeV/c, and intensity of 2 x 10/sup 10/ protons per pulse, were extracted to an external polarimeter at the Brookhaven AGS. In order to maintain this polarization, five intrinsic and nearly forty imperfection depolarizing resonances had to be corrected. An apparent interaction between imperfection and intrinsic resonances occurring at very nearly the same energy was observed and the correction of imperfection resonances using ''beat'' magnetic harmonics discovered in the previous AGS commissioning run was further confirmed.
Date: January 1, 1986
Creator: Ahrens, L. A.
System: The UNT Digital Library
Estimates of radionuclide release from glass waste forms in a tuff repository and the effects on regulatory compliance (open access)

Estimates of radionuclide release from glass waste forms in a tuff repository and the effects on regulatory compliance

This paper discusses preliminary estimates of the release of radionuclides from waste packages containing glass-based waste forms under the expected conditions at Yucca Mountain. These estimates can be used to evaluate the contribution of waste package performance toward meeting repository regulatory restrictions on radionuclide release. Glass waste will be held in double stainless steel canisters. After failure of the container sometime after the 300 to 1000 year containment period, the open headspace in these cans will provide the only area where standing water can accumulate and react with the glass. A maximum release rate of 0.177 g/m{sup 2} x year or 1.3 grams per year was obtained. Normalized loss of 1.3 grams per year corresponds to 0.08 parts in 100,000 per year of the 1660 kg reference weight of DWPF glass.
Date: April 1, 1986
Creator: Aines, R. D.
System: The UNT Digital Library
Insider Protection: A Report Card (open access)

Insider Protection: A Report Card

Enhanced security measures against external threats (e.g., terrorists, criminals) have been implemented at most facilities that handle special nuclear material, classified information, or other assets critical to national security. Attention is not focussing on insider protection, and safeguards managers are attempting to provide balanced protection against insider and outsider threats. Potential insider threats include attempts by facility employees to steal special nuclear material (SNM), to cause a radiological hazard to the public, to sabotage critical facilities, or to steal property or classified information. This paper presents a report card on the status of insider protection at Department of Energy and Nuclear Regulatory Commission-licensed facilities, with emphasis on SNM theft. We discuss the general trends in insider protection and the limitations of protection measures currently in use. We also discuss the most critical needs for improved procedures, technology, analytical tools, and education for safeguards personnel.
Date: January 1, 1986
Creator: Al-Ayat, R. A. & Judd, B. R.
System: The UNT Digital Library
Safeguards Evaluation Method for Evaluating Vulnerability to Insider Threats (open access)

Safeguards Evaluation Method for Evaluating Vulnerability to Insider Threats

As protection of DOE facilities against outsiders increases to acceptable levels, attention is shifting toward achieving comparable protection against insiders. Since threats and protection measures for insiders are substantially different from those for outsiders, new perspectives and approaches are needed. One such approach is the Safeguards Evaluation Method. This method helps in assessing safeguards vulnerabilities to theft or diversion of special nuclear meterial (SNM) by insiders. The Safeguards Evaluation Method-Insider Threat is a simple model that can be used by safeguards and security planners to evaluate safeguards and proposed upgrades at their own facilities. The method is used to evaluate the effectiveness of safeguards in both timely detection (in time to prevent theft) and late detection (after-the-fact). The method considers the various types of potential insider adversaries working alone or in collusion with other insiders. The approach can be used for a wide variety of facilities with various quantities and forms of SNM. An Evaluation Workbook provides documentation of the baseline assessment; this simplifies subsequent on-site appraisals. Quantitative evaluation is facilitated by an accompanying computer program. The method significantly increases an evaluation team's on-site analytical capabilities, thereby producing a more thorough and accurate safeguards evaluation.
Date: January 1, 1986
Creator: Al-Ayat, R. A.; Judd, B. R. & Renis, T. A.
System: The UNT Digital Library
Measurement of the fission cross section of /sup 238/Pu (open access)

Measurement of the fission cross section of /sup 238/Pu

The fission cross sections of /sup 238/Pu have been measured from 0.1 eV to 80 keV energy range using the Rensselaer Intense Neutron Spectrometer. The cross sections were normalized to the /sup 235/U ENDF/B-V data broadened to the resolution of the Rensselaer Intense Neutron Spectrometer system. The fission areas and widths were determined for the resolved low-energy resonances. The ENDF/B-V fission cross sections for the /sup 238/Pu isotope are, in general, not in good agreement with the measured cross sections and a new evaluation is recommended. The observations of structure in the unresolved fission cross sections is suggestive of the existence of intermediate structure. 18 refs., 1 fig., 1 tab.
Date: July 1, 1986
Creator: Alam, B.; Block, R. C.; Slovacek, R. E. & Hoff, R. W.
System: The UNT Digital Library
Effect of chain rigidity on conductivity of conjugated polymers (open access)

Effect of chain rigidity on conductivity of conjugated polymers

There are several ways to introduce processability to conjugated polymers, and one of them is discussed here. The basic approach involves the introduction of flexible centers in a conjugated backbone with a periodicity that allows the existence of conjugated sequences characterized by an electron mobility high enough to result in electronic conduction upon oxidation or reduction. The process consists of the use of AsF/sub 5/ as a polymerization catalyst, and AsF/sub 3/ as a non-conventional medium for the reaction. The Lewis acid coupling reactions, via which the polymerization occurs, result in soluble materials. Characteristics of the materials obtained by polymerizing acetylene and some aromatic compounds are discussed.
Date: January 1, 1986
Creator: Aldissi, M.
System: The UNT Digital Library