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Statistical Analyses of Scatterplots to Identify Important Factors in Large-Scale Simulations

Description: The robustness of procedures for identifying patterns in scatterplots generated in Monte Carlo sensitivity analyses is investigated. These procedures are based on attempts to detect increasingly complex patterns in the scatterplots under consideration and involve the identification of (1) linear relationships with correlation coefficients, (2) monotonic relationships with rank correlation coefficients, (3) trends in central tendency as defined by means, medians and the Kruskal-Wallis statistic, (4) trends in variability as defined by variances and interquartile ranges, and (5) deviations from randomness as defined by the chi-square statistic. The following two topics related to the robustness of these procedures are considered for a sequence of example analyses with a large model for two-phase fluid flow: the presence of Type I and Type II errors, and the stability of results obtained with independent Latin hypercube samples. Observations from analysis include: (1) Type I errors are unavoidable, (2) Type II errors can occur when inappropriate analysis procedures are used, (3) physical explanations should always be sought for why statistical procedures identify variables as being important, and (4) the identification of important variables tends to be stable for independent Latin hypercube samples.
Date: April 1, 1999
Creator: Kleijnen, J.P.C. & Helton, J.C.
Partner: UNT Libraries Government Documents Department

Statistical Analyses of Scatterplots to Identify Important Factors in Large-Scale Simulations, 2. Robustness of Techniques

Description: Procedures for identifying patterns in scatterplots generated in Monte Carlo sensitivity analyses are described and illustrated. These procedures attempt to detect increasingly complex patterns in scatterplots and involve the identification of (i) linear relationships with correlation coefficients, (ii) monotonic relationships with rank correlation coefficients, (iii) trends in central tendency as defined by means, medians and the Kruskal-Wallis statistic, (iv) trends in variability as defined by variances and interquartile ranges, and (v) deviations from randomness as defined by the chi-square statistic. A sequence of example analyses with a large model for two-phase fluid flow illustrates how the individual procedures can differ in the variables that they identify as having effects on particular model outcomes. The example analyses indicate that the use of a sequence of procedures is a good analysis strategy and provides some assurance that an important effect is not overlooked.
Date: March 24, 1999
Creator: Helton, J.C. & Kleijnen, J.P.C.
Partner: UNT Libraries Government Documents Department

Survey of sampling-based methods for uncertainty and sensitivity analysis.

Description: Sampling-based methods for uncertainty and sensitivity analysis are reviewed. The following topics are considered: (1) Definition of probability distributions to characterize epistemic uncertainty in analysis inputs, (2) Generation of samples from uncertain analysis inputs, (3) Propagation of sampled inputs through an analysis, (4) Presentation of uncertainty analysis results, and (5) Determination of sensitivity analysis results. Special attention is given to the determination of sensitivity analysis results, with brief descriptions and illustrations given for the following procedures/techniques: examination of scatterplots, correlation analysis, regression analysis, partial correlation analysis, rank transformations, statistical tests for patterns based on gridding, entropy tests for patterns based on gridding, nonparametric regression analysis, squared rank differences/rank correlation coefficient test, two dimensional Kolmogorov-Smirnov test, tests for patterns based on distance measures, top down coefficient of concordance, and variance decomposition.
Date: June 1, 2006
Creator: Johnson, Jay Dean; Helton, Jon Craig; Sallaberry, Cedric J. & Storlie, Curt B.
Partner: UNT Libraries Government Documents Department

Statistical Analyses of Scatterplots to Identify Important Factors in Large-Scale Simulations, 1: Review and Comparison of Techniques

Description: The robustness of procedures for identifying patterns in scatterplots generated in Monte Carlo sensitivity analyses is investigated. These procedures are based on attempts to detect increasingly complex patterns in the scatterplots under consideration and involve the identification of (i) linear relationships with correlation coefficients, (ii) monotonic relationships with rank correlation coefficients, (iii) trends in central tendency as defined by means, medians and the Kruskal-Wallis statistic, (iv) trends in variability as defined by variances and interquartile ranges, and (v) deviations from randomness as defined by the chi-square statistic. The following two topics related to the robustness of these procedures are considered for a sequence of example analyses with a large model for two-phase fluid flow: the presence of Type I and Type II errors, and the stability of results obtained with independent Latin hypercube samples. Observations from analysis include: (i) Type I errors are unavoidable, (ii) Type 11errors can occur when inappropriate analysis procedures are used, (iii) physical explanations should always be sought for why statistical procedures identify variables as being important, and (iv) the identification of important variables tends to be stable for independent Latin hypercube samples.
Date: March 24, 1999
Creator: Kleijnen, J.P.C. & Helton, J.C.
Partner: UNT Libraries Government Documents Department

Composite particle production in relativistic Au+Au collisions at AGS: First results from the E866 forward spectrometer @ 2, 4, and 10.8 A{center_dot}GeV

Description: Particle spectra were measured for Au + Au collisions at 2, 4, and 10. 8 A{center_dot}GeV using the E866 spectrometers. Recent results on proton emission and composite particle production form the E866 forward spectrometer data taken in 1994 together with the first results from the 1995/6 AGS running period are presented. Preliminary results indicate a decrease in the coalescence scaling coefficient with increasing projectile energy and centrality.
Date: December 31, 1996
Creator: Ashktorab, K.
Partner: UNT Libraries Government Documents Department

A FORTRAN 77 Program and User's Guide for the Statistical Analyses of Scatterplots to Identify Important Factors in Large-Scale Simulations

Description: A description and user's guide are given for a computer program, PATTRN, developed at Sandia National Laboratories for use in sensitivity analyses of complex models. This program is intended for use in the analysis of input-output relationships in Monte Carlo analyses when the input has been selected using random or Latin hypercube sampling. Procedures incorporated into the program are based upon attempts to detect increasingly complex patterns in scatterplots and involve the detection of linear relationships, monotonic relationships, trends in measures of central tendency, trends in measures of variability, and deviations from randomness. The program was designed to be easy to use and portable.
Date: August 1, 1999
Creator: Helton, Jon C. & Shortencarier, Maichael J.
Partner: UNT Libraries Government Documents Department

Rank correlation plots for use with correlated input variables in simulation studies

Description: A method for inducing a desired rank correlation matrix on multivariate input vectors for simulation studies has recently been developed by Iman and Conover (SAND 80-0157). The primary intention of this procedure is to produce correlated input variables for use with computer models. Since this procedure is distribution free and allows the exact marginal distributions to remain intact, it can be used with any marginal distributions for which it is reasonable to think in terms of correlation. A series of rank correlation plots based on this procedure when the marginal distributions are normal, lognormal, uniform, and loguniform is presented. These plots provide a convenient tool for both aiding the modeler in determining the degree of dependence among variables (rather than guessing) and communicating with the modeler the effect of different correlation assumptions. 12 figures, 10 tables.
Date: November 1, 1980
Creator: Iman, R.L. & Davenport, J.M.
Partner: UNT Libraries Government Documents Department

Sensitivity analyses for total-system performance assessment

Description: As a follow-on to Sandia`s 1991 preliminary total-system performance assessment of the Yucca Mountain site, this paper presents results of some sensitivity analyses that were done using results from the 1991 study. Two conceptual models of unsaturated-zone flow and transport at Yucca Mountain were included in the study, including both aqueous and gaseous releases. The sensitivities are quite different for the two models. For the composite-porosity model, the results are most sensitive to groundwater percolation flux, gaseous transport time, container lifetime, and fuel-matrix-alteration rate. For the weeps model, the results are most sensitive to parameters used to characterize fracture flow (fracture aperture and fracture connectivity) and infiltration (percolation flux and weep-episode factor).
Date: December 31, 1992
Creator: Wilson, M.L.
Partner: UNT Libraries Government Documents Department

Landau damping in the improved SLC linac: A, The sensitivity to injection jitter

Description: In this report we study the effects of injection jitter on emittance growth, and hence on luminosity, in the improved linac with stronger focusing, and for the new bunch parameters. We consider both cases when Landau damping has been invoked, and when it has not been.
Date: April 1, 1988
Creator: Bane, K.L.F.
Partner: UNT Libraries Government Documents Department

Data display with the Q system

Description: The Q data-acquisition system for PDP-11 mini-computers at the Clinton P. Anderson Meson Physics Facility (LAMPF) provides experimenters with basic tools for on-line data display. Tasks are available to plot one- and two-parameter histograms on Tektronix 4000 series storage-tube terminals. The histograms to be displayed and the display format may be selected with simple keyboard commands. A task is also available to create and display live two-parameter scatter plots for any acquired or calculated quantities. Other tasks in the system manage the display data base, list display parameters and histogram contents on hardcopy devices, and save core histograms on disk or tape for off-line analysis. 8 figures.
Date: January 1, 1979
Creator: Oothoudt, M.A.
Partner: UNT Libraries Government Documents Department

Search for rare muon and pion decay modes with the crystal box detector

Description: New experiental upper limits for the branching ratios of the lepton-family-number nonconserving decays ..mu../sup +/ ..-->.. e/sup +/..gamma.. and ..mu../sup +/ ..-->.. e/sup +/..gamma gamma.. are presented. A new determination of ..gamma.., the ratio of pion axial vector to vector form factors, from radiative pion decay is also reported. These results are from data taken with the Crystal Box detector at LAMPF. 11 refs., 7 figs.
Date: January 1, 1986
Creator: Piilonen, L.E.; Bolton, R.D.; Bowman, J.D.; Cooper, M.D; Frank, J.S.; Hallin, A.L. et al.
Partner: UNT Libraries Government Documents Department

High nuclear temperatures by antimatter-matter annihilation

Description: It is suggested that the quark-gluon phase be created through the use of antiproton or antideuteron beams. The first advantage to this method, using higher energy antiprotons than 1.5 GeV/c, is that the higher momenta antiprotons penetrate more deeply so that mesons produced are more nearly contained within the nucleus. Another advantage is that the annihilation products are very forward-peaked and tend to form a beam of mesons so that the energy density does not disperse very rapidly. Calculations were performed using the intranuclear cascade to try to follow the process of annihilation in some detail. The intranuclear cascade type calculation method is compared to the hydrodynamic approach. 8 refs., 8 figs. (LEW)
Date: January 1, 1985
Creator: Gibbs, W.R. & Strottman, D.
Partner: UNT Libraries Government Documents Department

Some calculator programs for particle physics. [LEGENDRE, ASSOCIATED LEGENDRE, CONFIDENCE, TWO BODY, ELLIPSE, DALITZ RECTANGULAR, and DALITZ TRIANGULAR codes]

Description: Seven calculator programs that do simple chores that arise in elementary particle physics are given. LEGENDRE evaluates the Legendre polynomial series ..sigma..a/sub n/P/sub n/(x) at a series of values of x. ASSOCIATED LEGENDRE evaluates the first-associated Legendre polynomial series ..sigma..b/sub n/P/sub n//sup 1/(x) at a series of values of x. CONFIDENCE calculates confidence levels for chi/sup 2/, Gaussian, or Poisson probability distributions. TWO BODY calculates the c.m. energy, the initial- and final-state c.m. momenta, and the extreme values of t and u for a 2-body reaction. ELLIPSE calculates coordinates of points for drawing an ellipse plot showing the kinematics of a 2-body reaction or decay. DALITZ RECTANGULAR calculates coordinates of points on the boundary of a rectangular Dalitz plot. DALITZ TRIANGULAR calculates coordinates of points on the boundary of a triangular Dalitz plot. There are short versions of CONFIDENCE (EVEN N and POISSON) that calculate confidence levels for the even-degree-of-freedom-chi/sup 2/ and the Poisson cases, and there is a short version of TWO BODY (CM) that calculates just the c.m. energy and initial-state momentum. The programs are written for the HP-97 calculator. (WHK)
Date: January 1, 1982
Creator: Wohl, C.G.
Partner: UNT Libraries Government Documents Department

Study of the radiative decay J/psi. -->. gamma. eta. pi. /sup +/. pi. /sup -/

Description: The Mark III collaboration has performed a high statistics study of the reaction J/psi ..-->.. ..gamma..eta..pi../sup +/..pi../sup -/, with two different final states of the eta, eta ..-->.. ..gamma gamma.. and eta ..-->.. ..pi../sup 0/..pi../sup +/..pi../sup -/. Both modes have a broad structure from 1.2 to 1.9 GeV/c/sup 2/ and two structures, which decay via delta/sup + -/..pi../sup - +/, delta/sup + -/ ..-->.. eta..pi../sup + -/, are identified at 1.28 and 1.39 GeV/c/sup 2/. No signal is observed in the iota(1440) signal region.
Date: February 1, 1987
Creator: Becker, J.J.; Blaylock, G.T.; Bolton, T.; Brown, J.S.; Bunnell, K.O.; Burnett, T.H. et al.
Partner: UNT Libraries Government Documents Department

From the neutron to three light neutrino species: Some highlights from sixty years of particle physics

Description: I consider the beginning to modern particle physics to be in 1932--33, when James Chadwick discovered the neutron at Cambridge, England, and Carl Anderson discovered the positron in Pasadena, California. I leave out the discoveries of the electron by J. J. Thomson, the nucleus and the proton by Ernest Rutherford, as well as the photon introduced by Albert Einstein and the neutrino as hypothesized by Wolfgang Pauli, as having occurred before my time.'' I was thus able to follow -- and sometimes participate in -- all the developments of modern particle physics. The story I will tell is as the unfolding of the field looked; to me -- an experimental particle physicists. As with Rashomon, this is as I see it. To get a different point of view, and no doubt there are many, you need different observer. One might ask, what did I know about physics in the 1930s, anyway It so happens that I did hear abut Chadwick's discovery at the time, mainly because my brother Maurice was working with him in 1934 on the photo-disintegration of the deuteron, and on the first good measurement of the neutron mass. I will concentrate on the thirty years, 1930 to 1960 which includes Dick Dalitz' important early contributions. I will then skip most of the next thirty years for lack of time, and end up with the study of the Z{sup 0} in e{sup +}e{sup {minus}} annihilation. For more details, and explicit references to published papers, I will refer the reader to a recent book by Robert Cahn and myself.
Date: July 1, 1990
Creator: Goldhaber, G.
Partner: UNT Libraries Government Documents Department

p anti p collider physics: summary talk

Description: Progress is very briefly summarized in these areas: Drell-Yan production of W and Z; inclusive spectra of jets; angular distribution of two jet final states; Dalitz plot analysis of three jet final states; interior structure of jets; minijets; issues and relevent data in soft-collision physics; structure of the pomeron; W, Z, and electroweak theory; heavy quark physics; extinct exotica; extant exotica, including monojets, the top quark, and possibly anomalous same-sign isolated dimuons. Future directions are anticipated for the Sp anti pS, Tevatron I, instrumentation and detectors, group theory, and the physics at SSC energies. 39 refs., 18 figs. (LEW)
Date: June 1, 1985
Creator: Bjorken, J.D.
Partner: UNT Libraries Government Documents Department

Recent results on D meson decays from the MARK III

Description: The MARK III Collaboration recently completed the analysis of a number of decay modes of charged and neutral D mesons produced in electron-positron collisions near the peak of the psi(3770) resonance at SLAC's SPEAR storage ring. The mesons were produced nearly at rest in pairs, either D/sup +/D/sup -/ or D/sup 0/ anti D/sup 0/, at a center-of-mass energy below the threshold for DD production. The unique kinematics of the production allow us to isolate the charmed meson signal clearly and unambiguously. The data were collected with the MARK III Spectrometer, a large solid angle magnetic detector. Our data sample corresponds to an integrated luminosity of approximately 9.3 inverse picobarns. New results will be presented on the absolute branching ratios of D mesons into hadronic final states, branching ratios for three body decays via pseudoscalar-vector intermediate states, and branching ratios for Cabibbo allowed and Cabibbo suppressed decays. Inclusive and exclusive branching ratios for the semi-leptonic decays of D mesons will be presented, as well as the first measurement of the vector form factor in the decay D/sup 0/ ..-->.. K/sup -/e/sup +/, nu, evidence for interference in D/sup +/ decays, and new information on the contributions of W exchange diagrams to D/sup 0/ decays.
Date: October 1, 1985
Creator: Coward, D.H.
Partner: UNT Libraries Government Documents Department

Recent results for Mark III

Description: This paper presents recent results from the Mark III detector at SPEAR, in the open charm sector. The first topic discussed is the reanalysis of the direct measurement of the D hadronic branching fractions, where a detailed study has been made of the Cabibbo suppressed and multi-..pi../sup 0/'s D decays backgrounds in the double tag sample. Next, the Dalitz plot analysis of the D decays to K..pi pi.. is presented, leading to the relative fractions of three-body versus pseudoscalarvector decays. 7 refs., 5 figs.
Date: December 1, 1987
Creator: Brient, J.C.
Partner: UNT Libraries Government Documents Department

Status and first results of Brookhaven Experiment 780: A search for K/sub L//sup 0/. -->. mu + e and K/sub L//sup 0/. -->. e + e

Description: We report on the progress of a search for the rare decays K/sub L//sup 0/ ..-->.. ..mu.. + e and K/sub L//sup 0/ ..-->.. e + e underway at the Brookhaven National Laboratory AGS. Analysis of data collected in February and May of 1987 yields the preliminary limit: BR(K/sub L//sup 0/ ..-->.. ..mu.. + e), BR(K/sub L//sup 0/ ..-->.. e + e) < 7 x 10/sup -9/. Prospects are discussed for the running period scheduled to begin in January of 1988.
Date: October 1, 1987
Creator: Greenlee, H.B.; Kasha, H.; Mannelli, E.; Mannelli, M.; Schaffner, S.; Schmidt, M.P. et al.
Partner: UNT Libraries Government Documents Department

Nucleon-nucleon resonances

Description: The experimental techniques related to NN resonance measurements are described. The technique used is the good geometry transmission experiment. The basic idea is to measure the difference in the attenuation factor for the corresponding difference between the total cross sections of N + N interactions for forward and reverse momentum as a function of the solenoid current. 26 references. (JFP)
Date: January 1, 1979
Creator: Auer, I.P.
Partner: UNT Libraries Government Documents Department

New results for rare muon decays

Description: Branching-ratio limits obtained with the Crystal Box detector are presented for the rare muon decays ..mu.. ..-->.. eee, ..mu.. ..-->.. e..gamma.., and ..mu.. ..-->.. e..gamma gamma... These decays, which violate the conservation of separate lepton-family numbers, are expected to occur in many extensions to the standard model. We found no candidates for the decay ..mu.. ..-->.. eee, yielding an upper limit for the branching ratio of B/sub ..mu..3e/ < 3.1 x 10/sup -11/ (90% C.L.). A maximum-likelihood analysis of the ..mu.. ..-->.. e..gamma.. candidates yields an upper limit of B/sub ..mu..e..gamma../ < 4.9 x 10/sup -11/ and an analogous analysis of ..mu.. ..-->.. e..gamma gamma.. candidates gives an upper limit of B/sub ..mu..e..gamma gamma../ < 7.2 x 10/sup -11/. These results strengthen the constraints on models that allow transitions between lepton families.
Date: January 1, 1986
Creator: Mischke, R.E.; Bolton, R.D.; Bowman, J.D.; Cooper, M.D.; Frank, J.S.; Hallin, A.L. et al.
Partner: UNT Libraries Government Documents Department

Increased statistics in. pi. /sup -/p. -->. phi phi n and the status of glueball production

Description: The statistics for the OZI forbidden reaction ..pi../sup -/p ..-->.. phi phi n have been doubled to a total of 6658 events, allowing extension of the phi phi partial wave analysis. A three-pole K-matrix fit was also obtained and Breit Wigners parameters deduced. Mass spectra, amplitudes from the partial wave analysis, and Argand diagrams for each wave are given. (LEW)
Date: January 1, 1987
Creator: Lindenbaum, S.J.; Etkin, A.; Foley, K.J.; Hackenburg, R.W.; Longacre, R.S.; Love, W.A. et al.
Partner: UNT Libraries Government Documents Department

Crystal Ball results on tau decays

Description: This report reviews measurements and upper limit determinations for a number of exclusive 1-prong tau decay modes using the Crystal Ball detector. These results are important input to the apparent discrepancy between the topological and sum-of-exclusive branching fractions in 1-prong tau decays.
Date: October 1, 1987
Creator: Lowe, S.T.
Partner: UNT Libraries Government Documents Department

Detection and study of new heavy particles through jet identification

Description: A solution to the problem of the identification of an arbitrary number of jets in high energy collisions is reviewed. Some of the applications of this solution to the study of the electroweak interactions are illustrated through two examples: the detection and analysis of top quarks, and the detection of charged Higgs or pseudo Goldstone bosons, in e/sup +/e/sup -/ reactions. Although these two examples involve e/sup +/e/sup -/ initial states, the jet identification method described in this paper could be used in the analysis of any reaction involving jets.
Date: January 1, 1981
Creator: Babcock, J.B.
Partner: UNT Libraries Government Documents Department