A realistic lattice model is a fundamental basis for the operation of a synchrotron. In this study various beam-based measurements, including orbit response matrix (ORM) and BPM turn-by-turn data are used to verify and calibrate the lattice model of the Fermilab Booster. In the ORM study, despite the strong correlation between the gradient parameters of adjacent magnets which prevents a full determination of the model parameters, an equivalent lattice model is obtained by imposing appropriate constraints. The fitted gradient errors of the focusing magnets are within the design tolerance and the results point to the orbit offsets in the sextupole field as the source of gradient errors. A new method, the independent component analysis (ICA) is introduced to analyze multiple BPM turn-by-turn data taken simultaneously around a synchrotron. This method makes use of the redundancy of the data and the time correlation of the source signals to isolate various components, such as betatron motion and synchrotron motion, from raw BPM data. By extracting clean coherent betatron motion from noisy data and separates out the betatron normal modes when there is linear coupling, the ICA method provides a convenient means to measure the beta functions and betatron phase advances. It also …

Evidence from observational cosmology and astrophysics indicates that about one third of the universe is matter, but that the known baryonic matter only contributes to the universe at 4%. A large fraction of the universe is cold and non-baryonic matter, which has important role in the universe structure formation and its evolution. The leading candidate for the non-baryonic dark matter is Weakly Interacting Massive Particles (WIMPs), which naturally occurs in the supersymmetry theory in particle physics. The Cryogenic Dark Matter Search (CDMS) experiment is searching for evidence of a WIMP interaction off an atomic nucleus in crystals of Ge and Si by measuring simultaneously the phonon energy and ionization energy of the interaction in the CDMS detectors. The WIMP interaction energy is from a few keV to tens of keV with a rate less than 0.1 events/kg/day. To reach the goal of WIMP detection, the CDMS experiment has been conducted in the Soudan mine with an active muon veto and multistage passive background shields. The CDMS detectors have a low energy threshold and background rejection capabilities based on ionization yield. However, betas from contamination and other radioactive sources produce surface interactions, which have low ionization yield, comparable to that of …

The first measurement of the top-antitop production cross section in proton-antiproton collisions at {radical}s = 1.96 TeV using 243 pb{sup -1} of data collected with the D0 detector at Fermilab is presented. In this analysis, only the dielectron final state is considered. Five events are observed, and 0.93 background events are expected. The measured cross section, after accounting for the expected branching ratio to the dielectron channel, is {sigma}{sub t{bar t}} = 14.9{sub -7.0}{sup +9.4}(stat){sub -1.8}{sup +2.5}(syst) {+-} 1.0 (lumi) pb, which agrees with the predicted cross section for top quarks with a mass of 175 GeV. In addition, a first-pass at a measurement of the top mass using the neutrino-weighting method is presented. This measurement is also performed in the dielectron channel using the five events observed in the cross section measurement.

A measurement of the inclusive Z/{gamma}* {yields} {mu}{sup +}{mu}{sup -} cross section for M{sub {mu}{mu}} > 40 GeV at {radical}s = 1.96 TeV is presented. The measurement is performed using a data sample corresponding to an integrated luminosity of 147.7 pb{sup -1}, collected with the D0 detector at the Tevatron, Fermilab, between September 2002 and October 2003. A total of 14352 di-muon events are selected and a final result of {sigma}(Z/{gamma}*) = 327.8 {+-} 3.4(stat.) {+-} 8.4(syst.) {+-} 21.3(lumi.) pb is obtained. Correcting the number of di-muon events by a factor of 0.885 {+-} 0.015 for the contribution from pure {gamma}* exchange and Z/{gamma}* interference, the inclusive Z {yields} {mu}{sup +}{mu}{sup -} cross section is found to be: {sigma}(Z) = 290.1 {+-} 3.0(stat.) {+-} 7.4(syst.) {+-} 18.9(lumi.) pb. Finally, comparisons of W and Z boson p{sub T} distributions as measured with D0 during Run I of the Tevatron are compared to HERWIG and MC{at}NLO predictions. Relevant parameters in the simulations are tuned to obtain the best possible fit to the data. An excellent agreement is found for both HERWIG and MC{at}NLO.

Two alternative measurements of the t{bar t} production cross section at {radical}s = 1.96 TeV in proton-antiproton collisions in the lepton+jets channel are presented. The t{bar t} production cross section is extracted by combining the kinematic event information in a multivariate discriminant. The measurement yields {sigma}{sub p{bar p} {yields} t{bar t} + x} = 5.13{sub -1.57}{sup +1.76}(stat){sub -1.10}{sup +0.96}(syst) {+-} 0.33 (lumi) pb in the muon+jets channel, using 229.1 pb{sup -1}, and in the combination with the electron+jets channel 226.3 pb{sup -1} {sigma}{sub p{bar p} {yields} t{bar t} + x} = 6.60{sub -1.28}{sup +1.37}(stat){sub -1.11}{sup +1.25}(syst) {+-} 0.43 (lumi) pb. The second measurement presented reconstructs explicitly secondary vertices to d lifetime b-tagging. The measurement combines the muon+jets and the electron+jets channel, using 158.4 pb{sup -1} and 168.8 pb{sup -1}, respectively: {sigma}{sub p{bar p} {yields} t{bar t} + x} = 8.24{sub -1.25}{sup +1.34}(stat){sub -1.63}{sup +1.89}(syst) {+-} 0.54 (lumi) pb.

In this dissertation, we measure the properties of the lowest-mass beauty baryon, {Lambda}{sub b}. Baryons are the bound states of three quarks. Protons and neutrons, constituents of atomic nuclei, are the most common baryons. Other types of baryons can be produced and studied in the high-energy collider environment. Three-body dynamics makes baryons composed of low mass quarks difficult to study. On the other hand, baryons with one heavy quark simplify the theoretical treatment of baryon structure, since the heavy quark can be treated the same way as the nucleus in the atom. The {Lambda}{sub b} is composed of u, d, and b quarks, where the b quark is much heavier than the other two. Although, it is accessible, little is known about {Lambda}{sub b}. In 1991, UA1 [1] reconstructed 9 {+-} 1 {Lambda}{sub b} {yields} J/{Psi}{Lambda} candidates. In 1996, ALEPH and DELPHI reconstructed the decay {Lambda}{sub b} {yields} {Lambda}{sub c}{sup +}{pi}{sup -} and found only 3-4 candidates [2, 3]. ALEPH measured a {Lambda}{sub b} mass of 5614 {+-} 21 MeV/c{sup 2}, while DELPHI measured 5668 {+-} 18 MeV/c{sup 2}, about 2 {sigma} higher. Subsequently, CDF-I observed 20 {Lambda}{sub b} {yields} J/{Psi}{Lambda} events [4], confirmed the existence of {Lambda}{sub b} unambiguously …

We present the results of a search for new particles decaying to tau pairs using the data corresponding to an integrated luminosity of 195 pb{sup -1} collected from March 2002 to September 2003 with the CDF detector at the Tevatron. Hypothetical particles, such as Z' and MSSM Higgs bosons can potentially produce the tau pair final state. We discuss the method of tau identification, and show the signal acceptance versus new particle mass. The low-mass region, dominated by Z {yields} {tau}{tau}, is used as a control region. In the high-mass region, we expect 2.8 {+-} 0.5 events from known background sources, and observe 4 events in the data sample. Thus no significant excess is observed, and we set upper limits on the cross section times branching ratio as a function of the masses of heavy scalar and vector particles.

High-precision measurements are made of Z boson production in proton-antiproton collisions at {radical}s = 1.96 TeV recorded by the Collider Detector at Fermilab, using the electron decay channel. The cross-section times branching ratio is measured to be {sigma}{sub Z} {center_dot} Br(Z {yields} e{sup +}e{sup -}) = (255.7 {+-} 2.4{sub stat} {+-} 5.2{sub sys} {+-} 15.2{sub lum})pb in a dataset of 194 pb{sup -1} collected between March 2002 and June 2003. This agrees well with theoretical predictions. The cross-section for W boson production in the electron channel has also been measured in the subset of this dataset of 72 pb{sup -1} collected up until January 2003. Using this smaller dataset the ratio of cross-sections is determined to be R {equivalent_to} {sigma}{sub W} {center_dot} Br(W {yields} e{nu})/{sigma}{sub Z} {center_dot} Br(Z {yields} ee) = 10.82 {+-} 0.18{sub stat} {+-} 0.16{sub sys}. Combining these results with measurements made in the muon channel gives R = 10.92 {+-} 0.15{sub stat} {+-} 0.14{sub sys} (e + {mu} channels), from which the branching ratio of the W to electrons and muons, and the total width of the W, have been extracted: Br(W {yields} {ell}{nu}) = 0.1089 {+-} 0.0022 ({ell} = e,{mu}); {Lambda}(W) = 2078.8 {+-} 41.4 MeV, …

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This thesis describes a study of the production of high transverse momentum direct photons and {pi}{sup 0} mesons by proton beams at 530 and 800 GeV/c and {pi}{sup -} beams at 515 GeV/c incident on beryllium, copper, and liquid hydrogen targets. The data were collected by Fermilab experiment E706 during the 1990 and 1991-92 fixed target runs. The apparatus included a large, finely segmented lead and liquid argon electromagnetic calorimeter and a charged particle spectrometer featuring silicon strip detectors in the target region and proportional wire chambers and drift tubes downstream of a large aperture analysis magnet. The inclusive cross sections are presented as functions of transverse momentum and rapidity. The measurements are compared with next-to-leading order perturbative QCD calculations and to results from previous experiments.

The Forward Proton Detector (FPD) is a new sub-system of the D0 detector, a 5000 ton particle physics detector located at the Fermilab Tevatron proton-antiproton collider. The FPD was implemented for the Tevatron Run II and gives access to a wide range of diffractive scattering processes, where one or both of the beam particles remain intact. The analysis described in this thesis makes use of the dipole spectrometer of the FPD to tag outgoing antiprotons in events that have a dijet signature in the central D0 calorimeter. Properties of jets with a diffractive tag signature are compared to jets without such a signature yielding the first observation of tagged diffractive dijets at a 1.96 TeV center-of-mass energy.

In the absence of external forces, if the dynamics within an electron beam is dominated by its angular momentum rather than other effects such as random thermal motion or self Coulomb-repulsive force (i.e., space-charge force), the beam is said to be angular-momentum-dominated. Such a beam can be directly applied to the field of electron-cooling of heavy ions; or it can be manipulated into an electron beam with large transverse emittance ratio, i.e., a flat beam. A flat beam is of interest for high-energy electron-positron colliders or accelerator-based light sources. An angular-momentum-dominated beam is generated at the Fermilab/NICADD photoinjector Laboratory (FNPL) and is accelerated to an energy of 16 MeV. The properties of such a beam is investigated systematically in experiment. The experimental results are in very good agreement with analytical expectations and simulation results. This lays a good foundation for the transformation of an angular-momentum-dominated beam into a flat beam. The round-to-flat beam transformer is composed of three skew quadrupoles. Based on a good knowledge of the angular-momentum-dominated beam, the quadrupoles are set to the proper strengths in order to apply a total torque which removes the angular momentum, resulting in a flat beam. For bunch charge around 0.5 nC, …

A search for charged massive stable particles has been performed with the D0 detector at the Fermilab Tevatron. The signature is two particles reconstructed as muons, but with speed and invariant mass inconsistent with beam-produced muons. No excess of events is observed and limits are set on the production cross-section for pair-produced stable stau sleptons based on 390 pb{sup -1} of data. Limits vary from 0.06 pb to 0.62 pb, depending on the stau mass, and are the strictest Tevatron limits to date. Mass limits are also set for stable charginos. The limits are 140 GeV/c{sup 2} for a higgsino-like chargino and 174 GeV/c{sup 2} for a gaugino-like chargino. These are currently the best limits to date for stable charginos.

This dissertation describes a measurement of the mass of the top quark using events consistent with the hypothesis t{bar t} {yields} bW{sup +} {bar b}W{sup -} {yields} bl{sup +}{nu}{bar b}l{sup -}{bar {nu}}, where (l=e,{mu}). The events are obtained from nearly 230 pb{sup -1} of p{bar p} collision data collected by the D0 experiment between 2002 and 2004 during Run II. In this decay channel two neutrinos remain undetected. Extraction of the mass of the top quark by kinematic reconstruction is not possible because the event is under-constrained. Therefore, a dynamical likelihood method is developed to obtain the mass of the top quark. The mass of top quark obtained from the candidate events selected in the di-electron channel and the e{mu} channel is: 154.1 {sup +14.2}{sub -12.8}(stat.) {+-}6.6 (syst.) GeV.

Using the data collected with the D0 detector at {radical}s = 1.96 TeV with integrated luminosities of about 180 pb{sup -1}, we have measured the ratio of inclusive cross sections for p{bar p} {yields} Z + b-jet to p{bar p} {yields} Z + jet production. The inclusive Z + b-jet reaction is an important background to searches for the Higgs boson in associated ZH production at the Fermilab Tevatron collider and is sensitive to the b quark content of the proton. This thesis describes our measurement which is performed using the dimuon decay channel of the Z boson, i.e. Z {yields} {mu}{sup +}{mu}{sup -}. The ratio in the dimuon channel is measured to be 1.86 {+-} 0.44(stat){sub -0.28}{sup +0.24}(syst)% for hadronic jets with transverse momenta p{sub T} > 20 GeV/c and pseudorapidities |{eta}| < 2.5, consistent with next-to-leading order predictions of the standard model. This measurement is also combined with the result of the same ratio using the dielectron decay of the Z boson, and the combined measurement of the ratio of cross-sections yields 2.11 {+-} 0.41(stat){sub -0.25}{sup +0.22}(syst)%. In addition to our measurement, we also study optimization procedures for the search of Z({mu} {bar {mu}})+b{bar b} signal at D0. …

We present measurements of the inclusive Drell-Yan e{sup +}e{sup -} differential cross section (d{sigma}/dM{sub e{sup +}e{sup -}}) and forward-backward asymmetry (A{sub FB}) as a function of the dielectron invariant mass over the range 70-400 GeV/c{sup 2}. The data sample consists of 177.3 pb{sup -1} of p{bar p} collisions at {radical}s = 1.96 TeV collected by the D0 detector. The results are consistent with the predictions of the standard model.

The MiniBooNE neutrino beam and detector at Fermilab are used to study the production of neutral current {pi}{sup 0} events. The cross sections for neutrino interactions with mineral oil (CH{sub 2}) are reported for resonantly produced and coherently produced single {pi}{sup 0} events. We measure a resonant single {pi}{sup 0} cross section of {sigma}({nu}{sub {mu}} N {pi}{sup 0}) = (0.0129 {+-} 0.0011(stat.) {+-} 0.0043(syst.)) x 10{sup -36} cm{sup 2}/CH{sub 2} at a mean neutrino energy of 1.26 GeV. We measure a coherent single {pi}{sup 0} cross section of {sigma}({nu}{sub {mu}} A {yields} {nu}{sub {mu}} A {pi}{sup 0}) = (0.00077 {+-} 0.00016 (stat.) {+-} 0.00036 (syst.)) x 10{sup -36} cm{sup 2}/CH{sub 2} at mean neutrino energy 1.12 GeV.

This thesis illustrates a complete study of the doubly and singly Cabibbo suppressed decays D{sup +} and D{sub s}{sup +} {yields} K{sup +} {pi}{sup -}{pi}{sup +}. Data for this analysis have been collected by the fixed-target high-energy photoproduction experiment FOCUS at Fermilab. The authors have selected the D{sup +} and D{sub s}{sup +} samples with cuts to obtain a sufficiently high statistics, a good signal to noise ratio and, at the same time, eliminate possible contaminations from the more copious and favored decays. The D{sup +} yield consists of 189 {+-} 24 events, with a signal to noise ratio {approx} 1; the D{sub s}{sup +} yield is 567 {+-} 31 and the signal to noise ratio is {approx} 2.5. The authors have measured {Lambda}(D{sup +} {yields} K{sup +}{pi}{sup -}{pi}{sup +})/{Lambda}(D{sup +} {yields} K{sup -}{pi}{sup +}{pi}{sup +}) = 0.0065 {+-} 0.0008 {+-} 0.004 and {Lambda}(D{sub s}{sup +} {yields} K{sup +}{pi}{sup -}{pi}{sup +})/{Lambda}(D{sub s}{sup +} {yields} K{sup +}K{sup -}{pi}{sup +}) = 0.127 {+-} 0.007 {+-} 0.014, improving the previous determinations of a factor of 2 and 5, respectively. The author has also performed a Dalitz plot analysis for both decays. The amplitude analysis for D{sub s}{sup +} {yields} K{sup +}{pi}{sup -}{pi}{sup +} …

This thesis presents a measurement of the t{bar t} cross section in the all-jets channel, measured in p{bar p} collisions at a center of mass energy of 1.96 TeV, using data collected with the D0 detector. The dataset used for this analysis has an integrated luminosity equivalent to L = 162.5 {+-} 10.6 pb{sup -1}. A t{bar t} cross section measurement is a test of the Standard Model predictions for heavy quark production, and the first step towards measurements of the mass and other properties of the top quark. The presented measurement of the cross section for the process p{bar p} {yields} t{bar t} uses the decay channel where both top quarks decay to quarks. The top quark first decays to a b quark and a W boson, and then, for this particular channel, the W boson decays hadronically. Hence, events with six energetic quarks are expected, which ideally leads to events with six jets. These so called all-jets events have a significantly larger branching fraction than other t{bar t} decay channels. The large branching fraction in the all-jets channel means that a significant sample of t{bar t} candidates can be extracted, which can subsequently be used for studies of …

A search for associated chargino neutralino pair production is performed in the trilepton decay channel q{bar q} {yields} {tilde {chi}}{sub 1}{sup {+-}} {tilde {chi}}{sub 2}{sup 0} {yields} {ell}{sup {+-}} {nu} {tilde {chi}}{sub 1}{sup 0} {mu}{sup {+-}} {mu}{sup {-+}} {tilde {chi}}{sub 1}{sup 0}, using data collected with the D0 detector at a center-of-mass energy of 1.96 TeV at the Fermilab Tevatron Collider. The data sample corresponds to an integrated luminosity of {approx}300 pb{sup -1}. A dedicated event selection is applied to all samples including the data sample and the Monte Carlo simulated samples for the Standard Model background and the Supersymmetry signal. Events with two muons plus an additional isolated track, replacing the requirement of a third charged lepton in the event, are analyzed. Additionally, selected events must have a large amount of missing transverse energy due to the neutrino and the two {tilde {chi}}{sub 1}{sup 0}. After all selection cuts are applied, 2 data events are found, with an expected number of background events of 1.75 {+-} 0.34 (stat.) {+-} 0.46 (syst.). No evidence for Supersymmetry is found and limits on the production cross section times leptonic branching fraction are set. When the presented analysis is considered in combination with …

The D0 detector underwent a major upgrade to maximize its ability to fully exploit Run II at the Fermilab Tevatron, the world's highest energy collider. The upgrade included a completely new central tracking system with an outer scintillating fiber tracker and an inner silicon vertex detector all within a 2T superconducting solenoid. This thesis describes the development of high level trigger algorithms including vertexing, impact parameter significance and invariant mass, that utilize tracks from these detectors. One of the main physics goals of Run II is the observation of B{sub s} oscillations. This measurement, which cannot be performed at the B factories, will significantly constrain the ''unitarity triangle'' associated with Cp violation and so probe the Standard Model of particle physics. Furthermore this is an interesting measurement as the study of mixing in meson systems has a long history for revealing new physics. The second part of this thesis presents a study of the hadronic decay B{sub s} {yields} D{sub s}{pi}. This important mode provides the best proper time resolution for B{sub s} mixing and is reconstructed for the first time at D0. Projections on the sensitivity to B{sub s} oscillations are then presented.

The new trigger processor, the Silicon Vertex Tracking (SVT), has dramatically improved the B physics capabilities of the upgraded CDF II Detector; for the first time in a hadron collider, the SVT has enabled the access to non-lepton-triggered B meson decays. Within the new available range of decay modes, the B{sub s}{sup 0} {yields} D{sub s}{sup -}{pi}{sup +} signature is of paramount importance in the measurement of the {Delta}m{sub s} mixing frequency. The analysis reported here is a step towards the measurement of this frequency; two where our goals: carrying out the absolute calibration of the opposite side flavor taggers, used in the {Delta}m{sub s} measurement; and measuring the B{sub d}{sup 0} mixing frequency in a B {yields} D{pi} sample, establishing the feasibility of the mixing measurement in this sample whose decay-length is strongly biased by the selective SVT trigger. We analyze a total integrated luminosity of 355 pb{sup -1} collected with the CDF II Detector. By triggering on muons, using the conventional di-muon trigger; or displaced tracks, using the SVT trigger, we gather a sample rich in bottom and charm mesons.

In this thesis two searches for electroweak single top quark production with the CDF experiment have been presented, a cutbased search and an iterated discriminant analysis. Both searches find no significant evidence for electroweak single top production using a data set corresponding to an integrated luminosity of 162 pb{sup -1} collected with CDF. Therefore limits on s- and t-channel single top production are determined using a likelihood technique. For the cutbased search a likelihood function based on lepton charge times pseudorapidity of the non-bottom jet was used if exactly one bottom jet was identified in the event. In case of two identified bottom jets a likelihood function based on the total number of observed events was used. The systematic uncertainties have been treated in a Bayesian approach, all sources of systematic uncertainties have been integrated out. An improved signal modeling using the MadEvent Monte Carlo program matched to NLO calculations has been used. The obtained limits for the s- and t-channel single top production cross sections are 13.6 pb and 10.1 pb, respectively. To date, these are most stringent limits published for the s- and the t-channel single top quark production modes.