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Dose commitments due to radioactive releases from nuclear power plant sites in 1992. Volume 14

Description: Population and individual radiation dose commitments have been estimated from reported radionuclide releases from commercial power reactors operating during 1992. Fifty-year dose commitments for a 1-year exposure from both liquid and atmospheric releases were calculated for four population groups (infant, child, teenager, and adult) residing between 2 and 80 km from each of 72 reactor sites. This report tabulates the results of these calculations, showing the dose commitments for both water and airborne pathways for each age group and organ. Also included for each of the sites is an estimate of individual doses, which are compared with 10 CFR Part 50, Appendix I, design objectives. The total collective dose commitments (from both liquid and airborne pathways) for each site ranged from a high of 3.7 person-rem to a low of 0.0015 person-rem for the sites with plants in operation and producing power during the year. The arithmetic mean was 0.66 person-rem. The total population dose for all sites was estimated at 47 person-rem for the 130-million people considered at risk. The individual dose commitments estimated for all sites were below the 10 CFR 50, Appendix I, design objectives.
Date: March 1, 1996
Creator: Aaberg, R.L. & Baker, D.A.
open access

Status of stable isotope enrichment, products, and services at the Oak Ridge National Laboratory

Description: The Oak Ridge National Laboratory (ORNL) has been supplying enriched stable and radioactive isotopes to the research, medical, and industrial communities for over 50 years. Very significant changes have occurred in this effort over the past several years, and, while many of these changes have had a negative impact on the availability of enriched isotopes, more recent developments are actually improving the situation for both the users and the producers of enriched isotopes. ORNL is still a major producer and distributor of radioisotopes, but future isotope enrichment operations conducted at the Isotope Enrichment Facility (IEF) will be limited to stable isotopes. Among the positive changes in the enriched stable isotope area are a well-functioning, long-term contract program, which offers stability and pricing advantages; the resumption of calutron operations; the adoption of prorated conversion charges, which greatly improves the pricing of isotopes to small users; SIO 9002 registration of the IEF`s quality management system; and a much more customer-oriented business philosophy. Efforts are also being made to restore and improve upon the extensive chemical and physical form processing capabilities that once existed in the enriched stable isotope program. Innovative ideas are being pursued in both technical and administrative areas to encourage the beneficial use of enriched stable isotopes and the development of related technologies.
Date: October 1, 1996
Creator: Aaron, W.S.; Tracy, J.G. & Collins, E.D.
open access

Color coherence in p pbar collisions at squareroot s = 1.8 TeV

Description: We report on two preliminary studies of color coherence effects on {ital p}{ital {anti p}} collisions based on data collected by the D{null} detector during the 1992-1993 and 1994-1995 runs at the Fermilab Tevatron collider at a center of mass energy {radical}s = 1. 8 TeV. Demonstration of initial-to-final state color interference effects is done in a higher energy region by measuring spatial correlations between the softer third jet and the second leading- {ital E}{sub {ital T}} jet in multi-jet events and in a lower energy regime by examining particle distribution patterns in W+Jet events. The data are compared to Monte Carlo simulations with different color coherence implementations and the predictions of an NLO parton level calculation.
Date: September 1, 1996
Creator: Abachi, S.
open access

The dijet mass spectrum and angular distributions with the D0 detector

Description: We present preliminary results from an analysis of dijet data collected during the 1994-95 Tevatron Collider run with an integrated luminosity of 91 pb{sup -1}. Measurements of dijet mass spectra and dijet angular distributions in {anti p}p collisions at {radical}s- = 1.8 TeV are compared with next-to-leading order QCD theory.
Date: July 1, 1996
Creator: Abachi, S.
open access

Direct photon measurements by the D{O} experiment

Description: We report a measurement of the cross section for production of isolated photons with transverse energy E{sub T} > 12 GeV in the central (absolute value of {eta} < 0.9) and forward (1.6 < absolute value of {eta} < 2.5) rapidity regions for {bar p}p collisions at center of mass energy {radical}s = 1.8 TeV, using an integrated luminosity of 13 pb{sup {minus}1}. The cross section is compared with a next-to-leading order (NLO) QCD calculation. We also present preliminary measurements of the center of mass scattering angle distribution and of the correlations between the rapidity of the photon and that of the leading jet in the event.
Date: July 1996
Creator: Abachi, S.
open access

A measurement of the ratio of W + 1 jet to W + 0 jets cross sections and comparisons to QCD

Description: A preliminary measurement of the ratio, R{sup 10}, of the production cross sections for W + 1 Jet and W + 0 Jets processes at {radical}s = 1,800 GeV by the D0 Collaboration is presented. A comparison of this ratio is made to next-to-leading order calculations and the implications of these comparisons, especially for the extraction of a value for the strong coupling constant {alpha}{sub s}(M{sub W}{sup 2}), are discussed.
Date: July 1996
Creator: Abachi, S.
open access

New phenomena results presented at the 1996 A.P.S. Division of Particles and Fields meeting

Description: This paper is a compendium of the D0 papers submitted to the 1996 Division of Particles and Fields meeting in Minneapolis/St. Paul, Minnesota. Each paper is reproduced here in full. The papers are: (1) a search for squarks and gluinos in the dielectron channel; (2) search for excited quarks decaying to two-jets with the D0 detector; (3) search for di-jet resonances produced in association with W bosons at D0; (4) search for first generation scalar leptoquarks at D0 detector; (5) search for SUSY gaugino production through the trilepton signature; (6) search for heavy neutral gauge bosons at D0.
Date: October 1, 1996
Creator: Abachi, S.
open access

Rapidity gaps between jets at D{O}

Description: We present studies of jet production via color-singlet events with low particle multiplicity between the jets. A preliminary study of the multiplicity in other regions of the color singlet events and the dependence of color-singlet exchange on jet transverse energy is also presented.
Date: July 1, 1996
Creator: Abachi, S.
open access

Results from a search for a neutral Scalar produced in association with a W boson in p pbar collisions at squareroot s = 1.8 TeV

Description: This paper presents a search for production of a hypothetical heavy particle {ital X} in association with a {ital W} boson. For the search presented here, the kinematics and acceptance are modelled under the assumption that the {ital X} particle has the spin and decay properties of the standard model Higgs boson with the modification that only {ital X} {r_arrow} {ital b}{ital {anti b}} decays are allowed. The {ital W} is required to decay via either the electron or muon mode. The complete D{null} 1992-1995 data set is used. This sample has an integrated luminosity of 100 pb{sup -1} and was taken at a center of mass energy of 1.8 TeV. Limits are placed on the number of associated production events and the production cross section.
Date: August 1, 1996
Creator: Abachi, S.
open access

Search for b {yields} X {mu} {sup +} {mu} {sup -} and B {sup 0} {yields} {mu} {sup +} {mu} {sup -} decays in p {anti p} Collisions at {radical} s= 1.8 TeV

Description: We have searched for the flavor-changing neutral current decays b {yields} X{mu}{sup +}{mu}{sup -} and B{sup 0} {yields} {mu}{sup +}{mu}{sup -} in p{anti p} collisions at {radical}s = 1.8 TeV with the D0 detector at Fermilab. Using our observed {mu}{sup +}{mu}{sup - } mass spectrum and the measured b production cross section we determine the 90% confidence limit for the branching fraction B(b {yields} s{mu}{sup +}{mu}{sup -}) < 3.6{times}10{sup -5}. For the exclusive, purely leptonic decay B{sup 0} {yields} {mu}{sup +}{mu}{sup -} we obtain a 90% confidence level limit B(B{sup 0} {yields} {mu}{sup +}{mu}{sup -}) < 8.0{times}10{sup -6}. 9 refs., 3 figs.
Date: August 1, 1996
Creator: Abachi, S.
open access

Small angle muon and b-quark production in p pbar collisions at squareroot s = 1.8 TeV

Description: We report on a measurement of small angle muon production (2.4 < {vert_bar}{ital y}{sup {mu}}{vert_bar} < 3.2) in {ital p}{ital {anti p}} collisions at {radical}s = 1.8 TeV with the D{null} detector at Fermilab. We have determined the fraction of the inclusive {mu} cross section in this region due to {ital b}-quark production and decay. Combining this measurement with our previously measured cross section in the central region, we calculate {ital d}{sigma}/{ital dy} for muons from {ital b} decay with {ital p}{sup {mu}}{sub T} > 5 GeV/c and {ital p}{sup {mu}}{sub T} > 8 GeV/c. These measurements are compared to next-to-leading order QCD calculations.
Date: August 1, 1996
Creator: Abachi, S.
open access

Hard single diffractive jet production at D0

Description: Preliminary results from the D{null} experiment on jet production with forward rapidity gaps in {ital p{anti p}} collisions are presented. A class of dijet events with a forward rapidity gap is observed at center-of-mass energies {radical}s = 1800 GeV and 630 GeV. The number of events with rapidity gaps at both center-of-mass energies is significantly greater than the expectation from multiplicity fluctuations and is consistent with a hard single diffractive process. A small class of events with two forward gaps and central dijets is also observed at 1800 GeV. This topology is consistent with hard double pomeron exchange.
Date: August 1, 1996
Creator: Abachi, S.; Abbott, B. & Abolins, M.
open access

Search for chargino-neutralino associated production via trileptonic final states with DO detector

Description: Preliminary results from a search for the production of an associated lightest chargino, W{sub 1}, and second lightest neutralino, Z{sub 2}, pair with the D0 detector at Fermilab`s pp collider with {radical}s = 1.8 TeV are presented. Based on approximately 85 pb{sup -1} of data collected during the 1993-1995 Tevatron Runs we set a 95% C.L. upper limit on the chargino-neutralino cross section times branching fraction to any trileptonic final state ranging from 0.91 pb to 0.19 pb for wino masses ranging from 45 GeV/c{sup 2} to 96 GeV/c{sup 2}.
Date: September 1, 1996
Creator: Abachi, S.; Ahn, S.; Baldin, B. & Bhat, P.C.
open access

An application of robust parameter design using an alternative to Taguchi methods

Description: The factors of interest in designing a product or process can generally be classified into two categories, controllable and uncontrollable. Controllable (or control) factors represent those factors which can be regulated. Examples of control factors include: the choice of material, flow rates, processing pressures, times and temperatures. Uncontrollable (noise) factors are those that are either difficult, impossible or too expensive to control during actual production or use. Examples of noise factors are: environmental conditions such as ambient temperature or humidity, process parameters which are dictated by an outside source such as end user demand, and usage factors such as how long and at what temperature a consumer stores a product. As compared to the current Tagachi approach, a new design method which provides greater flexibility in the design of the experiment, utilize a more meaningful performance statistic, and lend itself to a better understanding of the product or process is described in this paper.
Date: November 1, 1996
Creator: Abate, M. L.; Morrow, M. C. & Kuczek, T.
open access

Radiative higgs boson decays H {yields} f{anti f}{gamma}

Description: Higgs boson radiative decays of the form H {r_arrow} f{ovr f}{gamma} are calculated in the Standard Model using the complete one-loop expressions for the decay amplitudes. Contributions to the radiative width from leptons and light quarks are given. We also present e{ovr e} invariant mass distributions for H {r_arrow} e{ovr e}{gamma}, which illustrate the importance of the photon pole contribution and the effects of the box diagrams. 4 refs., 6 figs.
Date: October 10, 1996
Creator: Abbasabadi, A.; Bowser-Chao, D.; Repko, W.W. & Dicus, D.A.
open access

Sulfur removal in advanced two stage pressurized fluidized bed combustion. Technical report, December 1, 1994--February 28, 1995

Description: The objective of this study is to obtain data on the rates and the extent of sulfation reactions involving partially sulfided calcium-based sorbents, and oxygen as well as sulfur dioxide, at operating conditions closely simulating those prevailing in the second stage (combustor) of Advanced Two-Stage Pressurized Fluidized-Bed Combustors (PFBC). In these systems the CO{sub 2} partial pressure generally exceeds the equilibrium value for calcium carbonate decomposition. Therefore, calcium sulfate is produced through the reactions between SO{sub 2} and calcium carbonate as well as the reaction between calcium sulfide and oxygen. To achieve this objective, the rates of reaction involving SO{sub 2} and oxygen (gaseous reactant); and calcium sulfide and calcium carbonate (solid reactants), will be determined by conducting tests in a pressurized thermogravimetric analyzer (HPTGA) unit. The effects of sorbent type, sorbent particle size, reactor temperature and pressure; and O{sub 2} as well as SO{sub 2} partial pressures on the sulfation reactions rate will be determined. During this quarter, samples of the selected limestone and dolomite, sulfided in the fluidized-bed reactor during last quarter, were analyzed. The extent of sulfidation in these samples was in the range of 20 to 50%, which represent carbonizer discharge material at different operating conditions. The high pressure thermogravimetric analyzer (BPTGA) unit has been modified and a new pressure control system was installed to eliminate pressure fluctuation during the sulfation tests.
Date: March 1, 1996
Creator: Abbasian, J.
open access

Advanced Low-Temperature Fluid Bed Sorbents

Description: This paper discusses the results obtained in an ongoing study geared towards developing advanced mixed-metal oxide sorbents for desulfurization of coal-derived fuel gases in the temperature range of 350 to 550{degrees}C. The paper focuses on the study related to the development of durable sorbents suitable for fluidized-bed application and addresses thermodynamic considerations, sulfidation kinetics, regenerability, and the physical and chemical characteristics of a number of novel sorbents.
Date: December 31, 1996
Creator: Abbasian, J.; Slimane, R. B. & Wangerow, J. R.
open access

Cost Effective Machining and Inspection of Structural Ceramic Components for Advanced High Temperature Application. Final CRADA Report for CRADA Number Y-1292-0151

Description: This Cooperative Research and Development Agreement (CRADA) was a mutual research and development (R and D) effort among the participants to investigate a range of advanced manufacturing technologies for two silicon nitride (Si{sub 3}N{sub 4}) ceramic materials. The general objective was to identify the most cost-effective part manufacturing processes for the ceramic materials of interest. The focus was determining the relationship between material removal rates, surface quality, and the structural characteristics of each ceramic resulting from three innovative processes. These innovated machining processes were studied using silicon nitride advanced materials. The particular (Si{sub 3}N{sub 4}) materials of interest were sintered GS-44 from the Norton Company, and reaction-bonded Ceraloy 147-3. The processes studied included the following activities: (1) direct laser machining; (2) rotary ultrasonic machining; and (3) diamond abrasive grinding, including both resinoid and vitreous-bonded grinding wheels. Both friable and non-friable diamond types were included within the abrasive grinding study. The task also conducted a comprehensive survey of European experience in use of ceramic materials, principally aluminum oxide. Originally, the effort of this task was to extend through a prototype manufacturing demonstration of selected engine components. During the execution of this program, however changes were made to the scope of the project, altering the goals. The Program goal became only the development of assessment of their impacts on product strength and surface condition.
Date: November 29, 1996
Creator: Abbatiello, L. A. & Haselkorn, M.
open access

Quasi-free ({ital e,e`p}) reactions: the first look from CEBAF

Description: Coincidence cross sections for ({ital e,e{sup `}p}) quasi-elastic scattering were measured at CEBAF with high statistical precision for C, Fe, and Au targets for 0.6 {lt} Q{sup 2} {lt} 3.3 GeV{sup 2}. {ital E{sub m}} and {ital P{sub m}} distributions obtained from a preliminary analysis are in reasonable agreement with prior data from SLAC, The preliminary results are compared with a PWIA calculation to determine the nuclear transparency as a function of Q{sup 2} and A. A. Rosenbluth analysis to extract the longitudinal and transverse cross sections from these data is anticipated.
Date: November 1, 1996
Creator: Abbott, D.; Amatuoni, T. & Armstrong, C.
open access

Results from Sage

Description: The Russian-American Gallium Solar Neutrino Experiment (SAGE) is described. Beginning in September 1992, SAGE II data were taken with 55 tons of Ga and with significantly reduced backgrounds. The solar neutrino flux measured by 31 extractions through October 1993 is presented. The result of 69 {+-} 10 +5/{minus}7 SNU is to be compared with a Standard Solar Model prediction of 132 SNU.
Date: April 1, 1996
Creator: Abdurashitov, J. N.; Gavrin, V. N. & Girin, S. V.
open access

J/{psi} and {psi}{prime} production at CDF

Description: This paper presents measurements of the J/{psi} and {psi}{prime} production cross sections in p{ovr p} collisions at {radical}s = 1.8 TeV. The cross sections are measured in the kinematic region P{sub T} {gt} 5 GeV/c, {vert_bar}{eta}{vert_bar} {lt} 0.6 using the dimuon decay channel. The fraction of events from B decays is measured and used to calculate the J/{psi} and {psi}{prime} cross sections from B decay. The fraction of J/{psi} events from {chi}{sub c} decays is also measured and used to calculate the J/{psi} cross section from direct production. 11 refs., 5 figs., 1 tab.
Date: July 1, 1996
Creator: Abe, F.
open access

Measurement of the B+ and B0 Lifetimes With Topological Vertexing at SLD

Description: The lifetimes of the B{sup +} (B{sub u}) and B{sup 0} (B{sub d}) mesons have been measured using a sample of 150,000 hadronic Z{sup 0} decays collected by the SLD experiment at the SLC between 1993 and 1995. The analysis reconstructs the decay length and charge of the B meson using a novel topological technique. This method results in a high statistics sample of 6,033 (3,665) charged (neutral) vertices. The ratio of B{sup +}:B{sup 0} decays in the charged (neutral) sample is 1.8:1 (1:2.3).
Date: July 1, 1996
Creator: Abe, K.; Abe, K. & Abt, I.
open access

Measurement of the Z{sup 0}-Lepton Coupling Asymmetries A{sub l}

Description: The authors present direct measurements of the Z{sup 0}-lepton coupling asymmetries, A{sub e}, A{sub {mu}}, and A{sub {tau}}. It is based on a data sample selected from 170 k Z{sup 0} decays collected by the SLD detector. The Z`s are produced by collisions of polarized e{sup {minus}} with unpolarized e{sup +} bunches at SLC. The couplings are extracted from the measurement of the left-right forward-backward asymmetry for each lepton species. The preliminary results (using information from all leptonic data for A{sub e}) are: A{sub e} = 0.148 {+-} 0.016, A{sub {mu}} = 0.102 {+-} 0.033 and A{sub {tau}} = 0.190 {+-} 0.034.
Date: July 22, 1996
Creator: Abe, K.; Abe, K. & Abt, I.
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