B. Klima

A fully relativistic bound-state equation is used to study the spectra (and leptonic widths) of charmonium, $b$-quarkonium, $D$ mesons, $F$ mesons, $B$ mesons, and mesons composed of light quarks. The short-distance behavior of the interaction is that of asymptotically free QCD, while the largedistance interaction is a linear confining one whose Lorentz nature is either pure scalar or an equal mixture of vector and scalar. Multiquark states are accounted for in an approximate manner. An interesting dependence of the quark masses on the Lorentz nature of the long-distance interaction and on the overall mass scale of the system is obtained.

We have formulated a relativistic two-body equation for quark-antiquark bound states using the expansion in intermediate states. We have used the asymptotically free QCD gluon exchange with either a scalar or equal vector and scalar linear potential. Using these we have fitted the upsilon, charmonium, D, F, ss, s-u, d and u, d quark mesons for the rho and above. We have also calculated relativistically their widths, singlet-triplet and P-state splittings.

We present a measurement of the top quark pair (tt¯) production cross section (σtt¯) in pp¯ collisions at a center-of-mass energy of 1.96 TeV using 230 pb−1 of data collected by the DØ detector at the Fermilab Tevatron Collider. We select events with one charged lepton (electron or muon), large missing transverse energy, and at least four jets, and extract the tt¯ content of the sample based on the kinematic characteristics of the events. For a top quark mass of 175 GeV, we measure σtt¯=6.7−1.3+1.4(stat)−1.1+1.6(syst)±0.4(lumi)pb, in good agreement with the standard model prediction.

We have measured the cross sections for e+e− → e+e−, e+e− → μ+μ−, e+e− → γγ and e+e− → hadrons in an energy scan at center of mass energies between 39.79 and 46.72 GeV in 30 MeV steps. New spinless bosons, whose existence has been postulated as a possible means to explain the anomalously large radiative width of the Z0 found at the CERN SPS pp collider, are ruled out in the scan region. The data are used to set limits on the couplings to lepton, photon and quark pairs of bosons with masses above 46.72 GeV.

A novel technique for both online and offline computation is presented. With this technique, a reconstruction analysis in elementary particle physics, otherwise prohibitively long, has been accomplished. It will be used online in an upcoming Fermilab experiment to reconstruct more than 100000 events per second and to trigger on the basis of that information. The technique delivers 40 gigaoperations per second, has a bandwidth on the order of gigabytes per second, and has a modest cost. An overview of the program, details of the system, and performance measurements are presented.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">&gt;</ETX>

In a study of collisions of 27.5 GeV/{ital c} protons in liquid hydrogen we have observed enhanced production of oppositely charged hadron pairs when the relative velocity of the two hadrons in the pair rest frame approaches {alpha}{ital c}. The scale and velocity dependence of the enhancement agree well with the effect of the attractive Coulomb interaction as described by the Gamow factor.

To impart hands-on training in physics analysis, CMS experiment initiated the concept of CMS Data Analysis School (CMSDAS). It was born over three years ago at the LPC (LHC Physics Centre), Fermilab and is based on earlier workshops held at the LPC and CLEO Experiment. As CMS transitioned from construction to the data taking mode, the nature of earlier training also evolved to include more of analysis tools, software tutorials and physics analysis. This effort epitomized as CMSDAS has proven to be a key for the new and young physicists to jump start and contribute to the physics goals of CMS by looking for new physics with the collision data. With over 400 physicists trained in six CMSDAS around the globe, CMS is trying to engage the collaboration in its discovery potential and maximize physics output. As a bigger goal, CMS is striving to nurture and increase engagement of the myriad talents, in the development of physics, service, upgrade, education of those new to CMS and the career development of younger members. An extension of the concept to the dedicated software and hardware schools is also planned, keeping in mind the ensuing upgrade phase.

The CMS Data Analysis School is an official event organized by the CMS Collaboration to teach students and post-docs how to perform a physics analysis. The school is coordinated by the CMS schools committee and was first implemented at the LHC Physics Center at Fermilab in 2010. As part of the training, there are a number of "short" exercises on physics object reconstruction and identification, Monte Carlo simulation, and statistical analysis, which are followed by "long" exercises based on physics analyses. Some of the long exercises go beyond the current state of the art of the corresponding CMS analyses.

CDF and D0 have published or submitted for publication eleven papers [1-11] that include direct experimental measurements of the top quark mass. Each experiment has found that the lepton+jets channel [1,5,6,9,10,11,12] gives the most precise result. However, CDF and D0 have also measured the top quark mass in other decay topologies. Both D0 [2,6] and CDF [3,4] have published additional results in the dilepton channels, while CDF [8] has published a result in the all-hadronic channel. Our aim in this note is to reduce the overall uncertainty on the top quark mass measurement by combining the most recent and final of these measurements [1,2,3,7,8]. This note combines the mass from the five separate measurements taking into account the statistical and systematic uncertainties as well as the correlations in the systematic uncertainties. The final Tevatron top mass based on Run 1 data is m{sub t} = 174.3 {+-} 3.2(stat) {+-} 4.0(syst) GeV/c{sup 2}. Combining the statistical and systematic uncertainties, the top mass is m{sub t} = 174.3 {+-} 5.1 GeV/c{sup 2}.

A modular system to provide high speed simultaneous measurements of pulse area and time-of-flight for photomultiplier signals is described. By requiring a minimum pulse size and a time-of-flight signal within a gate before recording either measurement, the system achieves several advantages over other techniques. In particular, since no time is wasted reading channels without useful information, readout speed is enhanced. The system permits accurate measurements at rates exceeding 10 MHz per channel and can be read out without excessive dead time at rates up to approximately 100 kHz. Data storage problems are also reduced. Both pulse area and time-of-flight are measured using 128 bins (7 bits). Costs are less than $40 US per channel. Other advantages and design features are discussed.

and rapid reduction at 60/sup 0/C. Thus, the rate-limiting step at 26 or 40/sup 0/C was not the rate of formation of nitrous acid, which is assumed to be the active reducing species.

A. Makes any warranty or representation,exp ressed or implied, with respect to the accuracy, completencia, or ulaefulne88 of the fnformation

first emphasized. Systematic surveys, together with information accruing from process development, have extended the ranges of extractions that can be correlated in usefully generalized patterns, which in turn should accelerate the development of new applications. However, many more areas remain to be surveyed before the many pertinent variables will have been covered. New amines of all classes have become available at commercial, development, or researchsample levels, while a few previously promising amines have become less available. Descriptions and current sources are reviewed. (auth)

The emergence and progress of the COVID-19 pandemic has raised a number of issues, including the determinants of health that are (potentially) at risk for the spread and progression of the disease and may exacerbate regional health inequalities. The aim of this paper is to analyse demographic indicators (proportion of population aged 65 years and over and life expectancy) and indicators of health intervention (number of beds and number of doctors/1000 inhabitants) in relation to the COVID-19 diseases (proportion of infected and mortality of those infected with COVID-19 virus in districts of the Czech Republic). Data from 2020 and 2021 are analysed using correlation analysis (Pearson correlation coefficient), factor and cluster analysis. The results show that there is a moderate relationship between the proportion of infected persons and COVID-19 mortality. Factor analysis showed that the higher the proportions of persons aged 65 years and over, the higher the values of proportion of infected persons and the number of deaths (mortality). A favourable position in the evaluated indicators is in the cluster of districts of Brno-město and Ostrava-město, while an unfavourable position was identified in the cluster of districts of Český Krumlov, Domažlice, Jeseník, Prachatice, Rakovník, Rokycany and Tachov. The location of the districts and the indicators of health intervention create regional differentiations and cause health inequalities.

Highlights of the experimental results presented at the 39th Rencontres du Moriond on ``QCD and High Energy Hadronic Interactions'', which was held in La Thuile, Italy on Mar. 28 - Apr. 4, 2004 are briefly summarised.

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The results on the measurements of the top-quark mass, based on the data collected by the Tevatron experiments CDF and DO at Fermilab during Run I from 1992 to 1996, are summarized. The combination of the published results, taking correlated uncertainties properly into account, is presented. The resulting world average for the mass of the top quark is: $M_t = 178.0 \pm 4.3 GeV/c^2$, where the total error of consists of a statistical part of $2.7 GeV/c^2$ and a systematic part of $3.3 GeV/c^2$.

Recent results on top quark physics with the D0 experiment in pp collisions at {radical}s = 1.8 TeV are reported. The direct measurement of the top quark mass uses single lepton and dilepton events, giving the result m{sub top} = 172.1 {+-} 7.1 GeV/c{sup 2} . The measurement of the t{anti t} production cross section includes analyses from 9 top decay channels: dilepton, electron and neutrino, single leptons with and without b tagging, and all-jets (t{anti t} {r_arrow} b jets). The authors measured the t{anti t} production cross section to be 5.9 {+-} 1.7 pb at m{sub top} = 172.1 GeV/c{sup 2}. Preliminary results on a search for charged Higgs production in top events are presented.

We have searched for the pair production of first generation scalar leptoquarks using the full data set (123 pb**-1) collected with the D0 detector at the Fermilab Tevatron during 1992-1996. We observe no candidates, consistent with the expected background. We combine these new results from the ee + jets and enu + jets channels with the published nunu + jets result to obtain a 95% CL upper limits on the LQ pair production cross section as a function of mass and beta, the branching ratio to a charged lepton and a quark. Comparing to the NLO theory predictions, we set 95% CL lower limits on the LQ mass of 225, 204, and 79 GeV/c**2 for beta=1, 1/2, and 0, respectively. The results of this analysis rule out an interpretation of the excess of high Q**2 events at HERA as leptoquarks with LQ mass below 200 GeV/c**2 for values of beta &gt; 0.4.

Recent results on top quark physics with the D0 experiment in pbar-p collisions at sqrt(s) = 1.8 TeV for an integrated luminosity of 125 pb**-1 are reported. The direct measurement of the top quark mass uses single lepton and dilepton events, giving the result m(top) = 172.1 +/- 7.1 GeV/c**2. The measurement of the t-tbar production cross section includes analyses from 9 top decay channels: dilepton (t-tbar --> e+mu, e+e, and mu+mu), electron and neutrino (t-tbar --> e+nu), single leptons (t-tbar --> e + jets, t-tbar --> mu + jets) with and without b tagging, and all-jets (t-tbar --> 6 jets). We measure the t-tbar production cross section to be 5.9 +/- 1.7 pb at m(top) = 172.1 GeV/c**2. Combining the D0 and the CDF measurements of the top quark mass and combining their t-tbar cross sections, in both cases taking into account error correlations, yields unofficially sigma(t-tbar) = 6.7 +/- 1.3 pb at an averaged top quark mass of m(top) = 173.8 +/- 5.2 GeV/c**2. Preliminary results on a search for charged Higgs production in top events, t --> Higgs + b, are presented.

Recent results on top quark physics with the D0 experiment in pbar-p collisions at sqrt(s) = 1.8 TeV for an integrated luminosity of 125 pb**-1 are reported. The direct measurement of the top quark mass uses single lepton and dilepton events, giving the result m(top) = 172.1 +/- 7.1 GeV/c**2. The measurement of the t-tbar production cross section includes analyses from 9 top decay channels: dilepton (t-tbar --&gt; e+mu, e+e, and mu+mu), electron and neutrino (t-tbar --&gt; e+nu), single leptons (t-tbar --&gt; e + jets, t-tbar --&gt; mu + jets) with and without b tagging, and all-jets (t-tbar --&gt; 6 jets). We measure the t-tbar production cross section to be 5.9 +/- 1.7 pb at m(top) = 172.1 GeV/c**2. Combining the D0 and the CDF measurements of the top quark mass and combining their t-tbar cross sections, in both cases taking into account error correlations, yields unofficially sigma(t-tbar) = 6.7 +/- 1.3 pb at an averaged top quark mass of m(top) = 173.8 +/- 5.2 GeV/c**2. Preliminary results on a search for charged Higgs production in top events, t --&gt; Higgs + b, are presented.

The D0 collaboration reports on the observation of the Standard Model top quark in p{anti p} collisions at {radical}s = 1.8 TeV at the Fermilab Tevatron. The authors have searched for t{anti t} production with an integrated luminosity of approximately 50 pb{sup {minus}1} in the dilepton and single-lepton decay channels, with and without tagging of b quark jets. They observe 17 events with an expected background of 3.8 {+-} 0.6 events. The probability for an upward fluctuation of the background to produce the observed signal is 2 {times} 10{sup {minus}6} (equivalent to 4.6 standard deviations). The kinematic properties of the excess events are consistent with top quark decay. They measure the top quark mass to be 199{sub {minus}21}{sup +19} (stat.) {sub {minus}21}{sup +14} (syst.) GeV/c{sup 2} and its production cross section to be 6.4 {+-} 2.2 pb. D0 also sees a hadronic W mass peak (W {yields} jj) in the t{bar t} data events. Preliminary results from multivariate analyses and from the t{bar t} data events. Preliminary results from multivariate analyses and from the t{bar t} {yields} all-jets channel are discussed. Preliminary determination of the top quark mass using dilepton events yields 145 {+-} 25 (stat.) {+-}20 (syst.) GeV/C{sup 2}.

The D0 collaboration has searched for Top quark production at [radical][bar s] = 1.8 TeV in p[bar p] collisions at Fermilab using a data sample corresponding to an integrated luminosity of 1.1 pb[sup [minus] 1], collected during the 1992 Tevatron run. We report the preliminary results of a search for t[bar t] production in which the Top quark decays to a W boson plus ab quark where one W decaying leptonically and the other decaying hadronically. Future prospects for extending the search for Top in the lepton plus jets channel are discussed.

This brief talk will present the very preliminary results of an ongoing data analysis of the data from BNL E766. BNL E766 was an experiment to study heavy particle spectroscopy in np(15−24 GeV) and pp interactions (28 GeV). The following discussion pertains to the pp → ppKsoKπ run. (AIP)

This brief talk will present the very preliminary results of an ongoing data analysis of the data from BNL E766. BNL E766 was an experiment to study heavy particle spectroscopy in np(15/minus/24 GeV) and pp interactions (28 GeV). The following discussion pertains to the pp /r arrow/ ppK/sub s//sup o/K..pi.. run. (AIP)