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Measurement of the Ratio of Branching Fractions Br(Bs -> Ds- pi+)/Br(B -> D- pi+) at CDF-II

Description: The measurement of B{sub s}{sup 0} mixing is one of the flagship analyses for the Run II B physics program. The sensitivity of the measurement to the frequency of B{sub s}{sup 0} oscillations strongly depends on the number of reconstructed B{sub s}{sup 0} mesons. They present the measurement of the ratio of branching fractions Br(B{sub s}{sup 0} {yields} D{sub s}{sup -}{pi}{sup +})/Br(B{sup 0} {yields} D{sup -}{pi}{sup +}), which directly influences the number of B{sub s}{sup 0} events availabl… more
Date: March 1, 2004
Creator: Furic, Ivan Kresimir
Partner: UNT Libraries Government Documents Department
open access

A Measurement of the Lifetime of the Lambda_b Baryon with the CDF Detector at the Tevatron Run II

Description: In March 2001 the Tevatron accelerator entered its Run II phase, providing colliding proton and anti-proton beams with an unprecedented center-of-mass energy of 1.96 TeV. The Tevatron is currently the only accelerator to produce {Lambda}{sub b} baryons, which provides a unique opportunity to measure the properties of these particles. This thesis presents a measurement of the mean lifetime of the {Lambda}{sub b} baryon in the semileptonic channel {Lambda}{sub b}{sup 0} {yields} {Lambda}{sub c}{s… more
Date: December 1, 2004
Creator: Unverhau, Tatjana Alberta Hanna & U., /Glasgow
Partner: UNT Libraries Government Documents Department
open access

Search for Excited or Exotic Electron Production Using the Dielectron + Photon Signature at CDF in Run II

Description: The author presents a search for excited or exotic electrons decaying to an electron and a photon with high transverse momentum. An oppositely charged electron is produced in association with the excited electron, yielding a final state dielectron + photon signature. The discovery of excited electrons would be a first indication of lepton compositeness. They use {approx} 202 pb{sup -1} of data collected in p{bar p} collisions at {radical}s = 1.96 TeV with the Collider Detector at Fermilab durin… more
Date: July 1, 2004
Creator: Gerberich, Heather Kay & U., /Duke
Partner: UNT Libraries Government Documents Department
open access

Tests of Enhanced Leading Order QCD in W Boson plus Jet Production in 1.96-TeV Proton-Antiproton Collisions

Description: The authors have studied the W + {ge} n jets process in Tevatron Run II experiment. The data used correspond to a total integrated luminosity of 72 pb{sup -1} taken from March 2002 through January 2003. The lowest order QCD predictions have been tested with a new prescription of the parton-jet matching, which allows to construct the enhanced LO phase space. According to this procedure, one gets unique results which do not depend on unphysical bias of kinematical cuts to avoid the collinear/infr… more
Date: January 1, 2004
Creator: Tsuno, Soushi
Partner: UNT Libraries Government Documents Department
open access

Improving Performance in a Global Logistics Company: Operational Performance Before and After Process Improvement

Description: The purpose of this study was to determine the effectiveness of an intervention designed to eliminate damage notification failures in a customer-specific standard operating procedure used by a global logistics company. Process maps identified locations in the process where damage notification failures could most likely occur. A revised process was designed overnight to eliminate as many notification failure points as possible. In addition, a job aid was included to help facilitate the process c… more
Date: December 2004
Creator: Dearman, Shawn Kale
Partner: UNT Libraries
open access

The Effects of Descriptive Praise on Instructional Control Over Varied and Stereotyped Play of a Five-Year-Old Boy

Description: This study investigated the effects of instructional cues on varied and stereotyped play responses of one typically developing 5-year-old child. Responses were observed across four sets of play materials: blocks, DUPLO® blocks, markers and paints. Training included praise contingent upon forms consistent with the instruction. Two instructions were each trained with corresponding instruction signs, "Try something different" (on blue paper) and "Do the same thing" (on yellow paper) for block and … more
Date: December 2004
Creator: Bank, Nicole L.
Partner: UNT Libraries

The Effects of Self-evaluation and Response Restriction on Letter and Number Reversal in Young Children.

Description: The purpose of this study was to evaluate the effects of a training package consisting of response restriction and the reinforcement of self-evaluation on letter reversal errors. Participants were 3 typically developing boys between the age of 5 and 7. The results indicated that the training package was successful in correcting reversals in the absence of a model during training and on application tests. These improvements maintained during subsequent follow-up sessions and generalized across t… more
Access: Restricted to UNT Community Members. Login required if off-campus.
Date: August 2004
Creator: Strickland, Monica Kathleen
Partner: UNT Libraries
open access

Order effects of variability-contingent and variability-independent point delivery: Effects on operant variability and target sequence acquisition.

Description: Previous research has shown that variability is a reinforceable dimension of operant behavior. Additionally, it has been demonstrated that learning is facilitated when variability in responding is high. In this research, variability was observed within an operant composed of any sequence of six left and right key presses. Variability was either a requirement for point delivery (VAR conditions) or points were delivered independent of variability (ANY conditions). Two groups of college undergradu… more
Date: May 2004
Creator: Lee, Coral Em
Partner: UNT Libraries
open access

Mediated Generalization of the Effect of Reprimands Across Two Topographies of Self-Injury

Description: This study sought to assess the effects of pairing a neutral stimulus with a reprimand contingent on occurrences of two topographies of problem behavior. Using a multiple baseline withdrawal with a nested multi-element design, contingencies were first applied to eye poking and, subsequently, to a second behavior, skin picking. In each case, the participant wore wristbands (a previously neutral stimulus) during treatment sessions. Results indicated that the reprimands were effective in decreasin… more
Date: May 2004
Creator: Kliethermes, Lana L.
Partner: UNT Libraries

The Effects of Parent Training on the Amount and Variety of Food Consumed By a Child with Autism.

Description: The current study assessed the effectiveness of a training package, delivered in the form of a manual, to teach a parent to increase the variety and amount of food consumed by her son. The participant was a 5-year-old boy with Pervasive Developmental Disorder and limited food consumption. A changing criterion design across two variables, variety of food and quantity of food, was used. Results were that the parent who used the manual, with limited assistance from the experimenter, did succeed in… more
Access: Restricted to UNT Community Members. Login required if off-campus.
Date: May 2004
Creator: VanKirk, Tessa Schreiber
Partner: UNT Libraries
open access

The Effects of Sign Language on the Vocal Responses of a Child with Autism.

Description: Sign language is an effective form of alternative communication for persons with autism and other developmental disabilities. Only a few studies have systematically measured the effects of sign language on the vocal responses of its users. This study employed a multiple baseline design to evaluate the effects of sign language on the vocal responses of a four-year-old boy with autism. Results indicate that a reinforcement contingency placed only on sign responses is inadequate for maintaining vo… more
Date: May 2004
Creator: Scarbro-McLaury, Jill
Partner: UNT Libraries
open access

Effects of Prompting and Fading Procedures to Establish Following the Line of Regard in A Child with Autism

Description: Children with autism show deficits in communication skills, including joint attention, a component of which is following the line of regard. Two experiments were conducted. The first experiment examined how prompting and fading procedures effected following the line of regard in a child with autism. The second experiment examined this effect on the child's learning the names of novel objects. One 10-year-old boy, with a primary diagnosis of autism, participated. A changing criterion design… more
Date: December 2004
Creator: Horr, Amy C.
Partner: UNT Libraries

Functional analysis and elimination of SIB in an olive baboon (Papio hamadryas anubis).

Description: Self injurious behavior (SIB), such as self-biting and head-banging, has been reported to occur in approximately 10% of captive, individually housed primates (Novak, Kinsely, Jorgensen, and Hazen, 1998). Accounts of the causes of SIB range from environmental to physiological. However, to date, no researchers have investigated the possible influence of social consequences, delivered by handlers and keepers, in the maintenance of SIB. There is only one research report showing that self-injury can… more
Access: Restricted to UNT Community Members. Login required if off-campus.
Date: August 2004
Creator: Dorey, Nicole R.
Partner: UNT Libraries
open access

The Effect of Response Preclusion on Stereotypy and Play in a Child with Autism.

Description: This study investigates the effectiveness of response preclusion on stereotypic behavior (climbing and licking) and on play for a child with autism. Data were collected on stereotypic responses, play behavior, and the types of play materials the participant contacted. Implementation of response preclusion was followed by both a decrease in stereotypic behavior as well as an increase in play behavior. Play behavior did not return to baseline levels of responding during reversals to baseline, a… more
Date: December 2004
Creator: Delgado, Veronica
Partner: UNT Libraries
open access

A measurement of the t anti-t production cross-section in proton anti-proton collisions at s**(1/2) = 1.96-TeV with the D0 detector at the Tevatron using final states with a muon and jets

Description: A preliminary measurement of the t{bar t} production cross section at {radical}s = 1.96 TeV is presented. The {mu}-plus-jets final state is analyzed in a data sample of 94 pb{sup -1} and a total of 14 events are selected with a background expectation of 11.7 {+-} 1.9 events. The measurement yields: {sigma}{sub p{bar p} {yields} t{bar t} + X} = 2.4{sub -3.5}{sup +4.2}(stat.){sub -2.6}{sup +2.5}(syst.) {+-} 0.3(lumi.) pb. The analysis, being part of a larger effort to re-observe the top quark in … more
Date: February 1, 2004
Creator: Klute, Markus
Partner: UNT Libraries Government Documents Department
open access

The Production Cross Sections of the Weak Vector Bosons in Proton Antiproton Collisions at s**(1/2) = 1.96-TeV and a Measurement of the W Boson Decay Width

Description: The theory that describes the fundamental particle interactions is called the Standard Model, which is a gauge field theory that comprises the Glashow-Weinberg-Salam model [1, 2, 3] of the weak and electromagnetic interactions and quantum chromodynamics (QCD) [4, 5, 6], the theory of the strong interactions. The discovery of the W [7, 8] and Z [9, 10] bosons in 1983 by the UA1 and UA2 collaborations at the CERN p{bar p} collider provided a direct confirmation of the unification of the weak and … more
Date: April 1, 2004
Creator: Varganov, Alexei Valerievich
Partner: UNT Libraries Government Documents Department
open access

Experimental and Numerical Investigation of the Role of Initial Condition of the Dynamics of Rayleigh-Taylor Mixing

Description: Experiments and direct numerical simulations have been performed to examine the effects of initial conditions on the dynamics of a Rayleigh-Taylor mixing layer. Experiments were performed on a water channel facility to quantify the interfacial and velocity perturbations initially present at the two-fluid interface in a small Atwood number mixing layer. The measurements have been parameterized for implementation in numerical simulations of the experiment, and two- and three-dimensional direct nu… more
Date: August 16, 2004
Creator: Mueschke, N
Partner: UNT Libraries Government Documents Department
open access

Search for first-generation leptoquarks in the jets and missing transverse energy topology in proton-antiproton collisions at center-of-mass energy 1.96 TeV

Description: The authors performed a search for the pair production of first-generation leptoquarks using 191 pb{sup -1} of proton-antiproton collision data recorded by the CDF experiment during Run II of the Tevatron. The leptoquarks are sought via their decay into a neutrino and quark, which yields missing transverse energy and several high-E{sub T} jets. Several control regions were studied to check the background estimation from Standard Model sources, with good agreement observed in data. In the leptoq… more
Date: March 1, 2004
Creator: Tsybychev, Dmitri
Partner: UNT Libraries Government Documents Department
open access

Measurement of the top pair production cross section at CDF using neural networks

Description: In the Tevatron accelerator at Fermilab protons and antiprotons are collided at a 1.96 TeV center of mass energy. CDF and D0 are the two experiments currently operating at the Tevatron. At these energies top quark is mostly produced via strong interactions as a top anti-top pair (t{bar t}). The top quark has an extremely short lifetime and according to the Standard Model it decays with {approx} 100% probability into a b quark and a W boson. In the ''lepton+jets'' channel, the signal from top pa… more
Date: November 1, 2004
Creator: Marginean, Radu
Partner: UNT Libraries Government Documents Department
open access

Search for Gauge Mediated Supersymmetry in the gamma gamma missing ET Channel

Description: We present results on a search for Gauge Mediated Supersymmetry in the di-photon final state using Run II data collected by the D0 Experiment at the Fermilab Tevatron Collider. We discuss event selection, Standard Model backgrounds, and the lower limits on the lightest neutralino and chargino masses resulted from this analysis.
Date: December 1, 2004
Creator: Kesisoglou, Stilianos Isaak & U., /Brown
Partner: UNT Libraries Government Documents Department
open access

Mass spectrum analysis of K- pi+ from the semileptonic decay D+ --> K- pi+ mu+ nu

Description: The Higgs mechanism preserves the gauge symmetries of the Standard Model while giving masses to the W, Z bosons. Supersymmetry, which protects the Higgs boson mass scale from quantum corrections, predicts at least 5 Higgs bosons, none of which has been directly observed. This thesis presents a search for neutral Higgs bosons, produced in association with bottom quarks. The production rate is greatly enhanced at large values of the Supersymmetric parameter tan {beta}. High-energy p{bar p} collis… more
Date: March 1, 2004
Creator: Massafferri Rodrigues, Andre & /Rio de Janeiro, CBPF
Partner: UNT Libraries Government Documents Department
open access

Measurement of the W + gamma Production in Proton - Anti-proton Collisions at s**(1/2) = 1.96-TeV

Description: The authors present a measurement of the {bar p}p {yields} W{gamma} + X {yields} e{nu}{gamma} + X production cross section using data form the Collider Detector at Fermilab. The p{bar p} collisions were provided by the Tevatron Collider at a center of mass energy of 1.96 TeV. Electroweak theory includes the trilinear vector boson coupling, WW{gamma}, which contributes to the e{nu}{gamma} final state. The electron decay channel of the W provides a clean sample to study the production of diboson … more
Date: October 1, 2004
Creator: Kirby, Michael H. & U., /Duke
Partner: UNT Libraries Government Documents Department
open access

A Measurement of the production cross section of top-antitop pairs in proton-antiproton collisions at a center of mass of 1.96 TeV using secondary vertex b-tagging.

Description: A measurement of the t{bar t} pair production cross section is presented using 162 pb{sup -1} of data collected by the CDF experiment during Run II at the Tevatron. t{bar t} events in the lepton+jets channel are isolated by identifying electrons and muons, reconstructing jets and transverse missing energy, and identifying b jets with a secondary vertex tagging algorithm. The efficiency of the algorithm is measured in a control sample using a novel technique that is less dependent on the simulat… more
Date: December 1, 2004
Creator: Bachacou, Henri
Partner: UNT Libraries Government Documents Department
open access

Measurement of the t anti-t production cross-section at s**(1/2) = 1.96-TeV using lifetime tagging

Description: A measurement of the t{bar t} production cross section in the lepton+jets channels with the D0 detector at {radical}s = 1.96 TeV using the lifetime-tagging techniques is presented. The t{bar t} cross section is estimated from the combination of the e+jets and {mu}+jets channels. The obtained result {sigma}{sub t{bar t}} = 7.47{sub -1.14}{sup +1.22}(stat){sub -1.03}{sup +1.65}(syst) {+-} 0.49(lumi) pb is consistent with the Standard Model expectation.
Date: July 1, 2004
Creator: Khanov, Alexander
Partner: UNT Libraries Government Documents Department
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