The Physics of the B Factories

This work is on the Physics of the B Factories. Part A of this book contains a brief description of the SLAC and KEK B Factories as well as their detectors, BaBar and Belle, and data taking related issues. Part B discusses tools and methods used by the experiments in order to obtain results. The results themselves can be found in Part C

Analysis on the Issue of East Financial Integration

在1997年金融危机发生后，东亚各国和地区意识到过分依赖外国的资金存在着巨大的风险。因此，为了避免对外国资金的过分依赖防止危机再次发生，东亚各国和地区通过完善金融体系，加强金融合作以推进金融一体化。 在此背景下，本文对东亚金融的一体化程度做出分析。本文对东亚各国和地区金融一体化的必要前提：东亚货币金融合作，东亚各国和地区资本市场放松管制情况、各国和地区的资本流动以及各国和地区股票及债券市场的发展进行了定性分析和描述，同时对各国投资与储蓄的相关性、各国消费者通过金融市场分散风险的程度、各国股票市场以及各国债券市场与两大国际市场间的联系，对东亚各国和地区金融市场一体化程度进行了实证分析。本文的研...East Asia has realized that it has great risk to depend on the foreign capital, after 1997 financial crisis. East Asia tried to improve the financial system and strengthen financial cooperation, so as to avoid the recurrence of financial crisis. This thesis tries to address the issue of the financial integration of East Asia. First of all, the basis of financial integration of East Asia was anal...学位：经济学博士院系专业：经济学院国际贸易系_世界经济学号：2005140292

MULTIPLICITY DEPENDENCE OF MEAN TRANSVERSE-MOMENTUM IN E+E- ANNIHILATIONS AT LEP ENERGIES

A strong increase of the mean transverse momentum [p(t)] with the number of charged particles n(ch) is observed in e+e- annihilations into hadrons at LEP energies, The effect resembles correlations observed in hadron-hadron interactions. In e+e- annihilations the [p(t)] and n(ch) correlations can be accounted for by gluon radiation

Observation of charge-ordering in particle production in hadronic Z(0) decay

Analysis of the rapidity structure of charge correlations in hadronic events from Z(0) decays gives evidence for chain-like charge-ordering of particle production along the thrust axis, as predicted by ‘QCD-motivated’ string-like fragmentation models. (C) 1997 Published by Elsevier Science B.V

SEARCH FOR SCALAR LEPTOQUARKS FROM Z(0) DECAYS

We have searched for pair produced scalar leptoquarks each decaying to a quark and a charged lepton in a sample of 116 000 hadronic Z0 events produced at LEP. No candidate was detected and cross section and branching ratio limits are set for the above process at 95% CL. Mass limits are found to be about 42 GeV/c2 depending only slightly on the models used and a coupling times branching ratio exclusion line is drawn for a scalar leptoquark with a free coupling. We have also probed the mass region above 45 GeV/c2 for a singly produced scalar leptoquark and set limits on the cross section and the coupling lambda(2)/4-pi up to 60 GeV

INCLUSIVE MEASUREMENTS OF THE K+/- AND P/(P)OVER-BAR PRODUCTION IN HADRONIC Z(0) DECAYS

This analysis, based on a sample of 170000 hadronic Z(0) decays, provides a measurement of the K-+/- and p/($) over bar p differential cross sections which is compared to string- and cluster fragmentation models. The total multiplicities for K-+/- and pip per hadronic event were found to be: N-K = 2.26 +/- 0.18 and N-p = 1.07 +/- 0.14. The positions xi* of the maxima of the differential cross sections as a function of xi = In(1/x(p)) for K-+/- and p/($) over bar p were determined to be 2.63 +/- 0.07 and 2.96 +/- 0.16 respectively. A comparison of the xi* values for various identified particles measured at LEP with the prediction of the Modified Leading Logarithm Approximation with Local Parton Hadron Duality model has been performed. The measured xi* position as a function of the hadron mass, after corrections due to particle decays, is in agreement with the model calculation

Search for neutral Higgs bosons in e(+)e(-) collisions at root s=183 GeV

Neutral Higgs bosons were searched for in the data collected by DELPHI at a centre-of-mass energy of 183 GeV, corresponding to an integrated luminosity of 54 pb(-1). The production of the lightest neutral Higgs boson with either an on-shell Z boson or a neutral pseudo-scalar Higgs boson was analysed. Lower limits at the 95% confidence level were obtained on the Higgs boson masses. The limits are 85.7 GeV/c(2) for the Standard Model Higgs boson and 74.4 GeV/c(2) for the scalar and 75.3 GeV/c(2) for the pseudo-scalar Higgs bosons as predicted by the minimal super-symmetric extension of the Standard Model with commonly used assumptions on the model parameters, plus the assumption that the mass of the pseudo-scalar boson is greater than 20 GeV/c(2). These results significantly improve the limits reached with previous data

Lambda(b) polarization in Z(0) decays at LEP

The longitudinal polarization of the Lambda(b) baryon is measured at the LEP e(+)e(-) collider by DELPHI. It is determined from the charged lepton and neutrino energy spectra in 249 +/- 19 Lambda(b) semileptonic decays reconstructed in approximate to 3.5 million hadronic Z(0) decays using Lambda(0)-lepton correlations. The measured polarization is: P-Lambda b = -0.49(-0.30)(+0.32)(stat.) +/- 0.17(syst.). (C) Elsevier Science B.V. All rights reserved

Measurements of the leptonic branching fractions of the tau

Data collected with the DELPHI detector from 1993 to 1995 combined with previous DELPHI results for data from 1991 and 1992 yield the branching fractions B(tau –> e nu<(nu)over bar>) = (17.877 +/- 0.109(stat) +/- 0.110(sys))% and B(tau –> mu nu<(nu)over bar>) = (17.325 +/- 0.095(stat) +/- 0.077(sys))%