Jonghee Yoo: "A study of short-time Periodic Variation of the 8B Solar Neutrino Flux at Super-Kamiokande"
Abstract: Super-Kamiokande(SK) is a real-time detector capable of measuring the exact time of solar neutrino events. This, combined with a relatively high yield of these events of roughly 15 per day, allows a search for short-time variations in the observed flux. Using all 1496 days of SK-I's solar data, we looked for periodic variations of the observed solar neutrino flux, and found no significant periodicity. The Lomb test was used to find possible periodicities in the measured fluxes of 10 day long samples.
Alexander Sherstnev: "Spin correlations in single top production in electron-gamma collisions"
Abstract: Spin correlations in single top production in electron-gamma collisions are analysed. Because of the unique V-A structure of the top interaction in the Standard Model with b-quark and W-boson the top quark is produced practically 90% polarized in the direction of incoming photon beam in the rest frame of the top. Also a comparison with single top production in hadron-hadron scattering is made.
Omer Yavas: "Future Lepton-Hadron Colliders "
Abstract: The main parameters of future lepton-hadron colliders are estimated. Namely, eRHIC, THERA and Linac*LHC based ep, photon-p, eA, photon-A and FEL photon-A colliders are considered. The physics serach potential of these machines is briefly discussed.
Michael Unger: "Measurement of the atmospheric muon spectrum from 40 to 2000 GeV/c with the L3+C detector"
Abstract: The L3+C experiment uses the precision muon spectrometer of the L3 detector at the e+e- collider LEP at CERN, Geneva, to measure the momentum of atmospheric muons.
Results on the absolute muon flux as a function of momentum and zenith angle are presented. The measurement covers momenta from 40 to 2000 GeV/c and and zenith angles from 0 to 60 degrees. The momentum and angular dependence of the muon charge ratio has also been measured between 40 to 600 GeV/c.
O.N. Shekhovtsova: "Radiative Events in DIS of Unpolarized Electrons by Tensor-polarized Deuterons"
Abstract: Deep Inelastic Scattering of unpolarized electrons by tensor-polarized deuterons with a tagged collinear photon, radiated from the initial electron, is considered. The cross section is derived in the Born approximation. The model-independent QED corrections to the Born cross section are also calculated using an approach based on the account of all essential Feynman diagrams.
Rudolf Faustov: "Hyperfine Splitting and Leptonic Decay Rates in Heavy Quarkonia"
Abstract: The hyperfine splitting in heavy quarkonia is considered in its relation to the leptonic decay rates with the account of relativistic and radiative corrections. The calculated decay rates agree well with the available experimental data, while the predicted etac(2S) mass is significantly smaller than the value measured recently by the Belle Collaboration.
Dmitriy Anipko: "Monte Carlo Simulation of Exclusive Channels in e+e- Annihilation at Low Energy"
Abstract: We have developed a software package for Monte Carlo simulation of exclusive channels in e+e- annihilation. The framework includes matrix elements for several mechanisms of multipion production calculated with the assumption of consequent two and three-body resonance decays. The matrix elements are written in a gauge-invariant shape. Presence of different isospin variations of a single production mechanism and their contribution to several charge variations of a single final state are accounted automatically. The software has extensible structure allowing to develop new matrix elements for different processes and to add them to the framework easily using late binding technique. The framework is developed in C++ programming language and runs under Linux operating system.
Borislav Pavlov: "CMS Resistive Plate Chambers - Tests and Results"
Abstract: The CMS Experiment will use Resistive Plate Chambers as a Dedicated Muon Trigger Detectors. Resistive Plate Chambers are Gaseous Parallel Plate Detectors comparable to that of a Scintillator (~1ns) and Good Spatial Resolution (~cm). The First 24 Resistive Plate Chambers for the Barrel Muon System of the CMS Experiment have been assembled and tested. A brief Description of the Cosmic Muon Telecope used for the Tests is given. The Detailed Studies of the Chamber Parameters (Efficiency, Cluster Size, Noise Rate and Dark Current) at Different High Voltages are Presented on the Poster.
Armine Rostomyan: "Measurement of Transversity at HERMES"
Abstract: We present HERMES results on single spin asymmetry in the electroproduction of charged and neutral pions. Data was obtained with longitudinally polarized target and unpolarized positron beam as well as with the unpolarized target and polarized beam. In addition we will present status of experiment with transversely polarized target. These measurements allow to access various unknown chiral-odd and/or time-odd structure functions for the first time.
Javi Fernandez: "Final results from DELPHI on the searches for SM and MSSM Neutral Higgs bosons"
Abstract: These final results from DELPHI searches for the Standard Model SM Higgs boson, together with benchmark scans of the Minimal Supersymmetric Standard Model MSSM neutral Higgs bosons, used data taken at centre-of-mass energies between 200 and 209GeV with a total integrated luminosity of 224inv. pb.The data from 192 to 202GeV are reanalysed with improved b-tagging for MSSM final states decaying to four b-quarks. The 95% confidence level lower mass bound on the Standard Model Higgs boson is 114.1GeV. Mass limits are also given on the lightest scalar and pseudo-scalar Higgs bosons of the MSSM.
Marek Kowalski: "Search for exotic particles with the Amanda Neutrino Telescope"
Abstract: Data taken with the Amanda neutrino telescope between 1997 and 199 have been analyzed for signatures of exotic particles beyond the standard model. Relativistic magnetic monopoles would be characterized by a light output about 8000 times that of minimum ionizing muons. An excess of neutrinos from the center of the Earth or from the Sun would indicate annihilations of WIMPs which have been accumulated in these celestial bodies. We present the limits obtained and compare them to astrophysical bounds as well as to predictions made by Minimum Supersymmetric Models.
I. Marfin et al.:" Study of Boson Vertices at Photon Colliders in the Standard Model and Beyond"
Abstract: The quartic gauge boson vertices in WW- and WWZ- production in photon-photon scattering are investigated at TESLA kinematics. The Lorentz-invariant formulae of the considered vertices are obtained within various non-minimal gauge models of electroweak interaction. In addition, the main radiative effects to gg -> WW are included. The dependences of the cross sections on various anomalous constants given by the considered models are presented.
Carlos Garcia Canal et al.: "NLO Scale Dependence of Semi-Inclusive Processes"
Abstract: The O(alphas²) gluon-initiated QCD corrections tp one particle deep inelastic processes have explicitely been computed. In order to deal with the nontrivial singularity structure characteristic of these processes, we have implemented a general approach for the prescription of overlapping singularities and extended the results for the 3-particle final state angular integrals. By the replacement of the bare parton densities, fragmentation and fracture functions with the corresponding renormalized quantities we have explicitely verified the factorisation of collinear singularities, obtaining for the first time the relevant kernels of this order. We also derived the evolution equations for fracture functions valid at NLO. Regarding the phenomenological consequences of these correction, we have found that O(alphas²) contributions to the evolution equations are mild in most of the kinematical range. However, for small values of xB, this NLO contributions are as important or even larger than the alpha_s ones. This behaviour, at variance with the LO case, allows the non homogeneous effects in the evolution of fracture functions to be sizeable even at larger hadron momentum fractions, thus being relevant for the scale dependence in the cases of diffractive and leading baryon processes.
Sandra Horvat: "Precision Drift Chambers for the ATLAS Muon Spectrometer"
Abstract: ATLAS is a multi-purpose detector under construction to search for the Higgs sector and new physics at the Large Hadron Collider (LHC) at CERN. An important part of the detector is the Muon Spectrometer designed to measure muon momenta with 3-10% resolution over a wide momentum range (10 - 1000 GeV/c). The muon trajectories are measured by three stations of precision drift chambers, the monitored drift tube (MDT) chambers.
The MDT chambers consist of two triple- or quadruple-layers of drift tubes, filled with an Ar:CO2 gas mixture at 3 bar pressure. The drift tubes have to provide an average spatial resolution of 100 microns. In addition, the signal wires have to be positioned within the chamber with an accuracy of better than 20 microns. The chamber production is fully on the way with 70% of the chambers already being constructed. During the chamber assembly, the positioning of the signal wires is continuously monitored with elaborate mechanical and optical devices. The mechanical precision has been demonstrated by X-ray measurements at CERN.
The environment in which the chambers will be operated is characterized by high neutron and photon background with expected counting rates of up to 100 Hz/cm2. The performance of chambers from the serial production has been studied in a muon beam at varying photon irradiation rates of up to 183 Hz/cm2 at the gamma-ray irradiation facility at CERN. A silicon strip detector is used as an external reference in the beam. The average spatial resolution of 100 microns at low rates is degraded by 10 microns at the highest rates in ATLAS, to which 20% of the chambers will be exposed. The measurements also prove that an efficient track reconstruction will be possible in the muon spectrometer under the expected background rates.
Lutz Bornschein: "KATRIN - Direct measurement of neutrino masses in the sub-eV region"
Abstract: The main motivations for neutrino mass measurements come from cosmology and particle physics.Neutrinos with masses in the sub-eV range could play an important role as hot dark matter in theevolution of large scale structures of the universe, and a measurement of the absolute mass scaleof neutrinos could be decisive in selecting different neutrino mass models.
The Karlsruhe Neutrino Mass Experiment (KATRIN) is a next generation tritium beta decay experiment with a sub-eV neutrino mass sensitivity. KATRIN will allow to investigate the role of the neutrino hot dark matter and will also allow to discriminate between so-called hierachical and quasi-degenerated neutrino mass modells.
The key components of KATRIN comprise a windowless gaseous molecular tritium source, an electron transport and tritium recovery and retention system, a tandem spectrometer system based on the principle of magnetic adiabatic collimation combined with an electrostatic filter (MAC-E-Filter) and a solid state detector for beta counting. The over all length of the Experiment will be about 70m, the diameter of the spectroveter vessel will be 10m, the vacuum conditions inside the spectrometer must be better than 1E-11 mbar.
The status of the first components of the final KATRIN setup and results of first measurements with a vacuum test chamber will be shown. Furthermore an estimate for the sensitivity of KATRIN on the neutrino mass under realistic assumptions for systematic and statistic will be given.
Hubert Simma: "APE Computers for Simulations in Lattice Gauge Theory"
Abstract: We present the APE (Array Processor Experiment) project for the development of dedicated parallel computers for numerical simulations in lattice gauge theories. We describe the application of the APEmille machines in today's physics simulations at various sites in Europe, and present the architectural improvements and project status of the new machine generation, apeNEXT, which is being developed to provide multi-Tflops computing performance for simulations of Lattice QCD. Furthermore, we will give an overview about planned physics projects which will rely on the compute power of large apeNEXT installations.
Ullrich Schwanke: "Status of the H.E.S.S. Experiment"
Abstract: The High Energy Stereoscopic System (H.E.S.S.) is a new generation atmospheric Cherenkov detector dedicated to the study of non-thermal phenomena in the Universe. Its sensitivity is expected to be an order of magnitude better than that of existing telescope systems. The experiment is located in the Khomas Highland of Namibia and has started data-taking in June 2002. The first phase of the experiment consists of a square array of four telescopes two of which are already operational. Each telescope has a total mirror area of 107 m2 and shower images are recorded by a camera consisting of 960 photo-multipliers. The poster presentation provides an overview of the H.E.S.S. experiment and presents first results from the observation of TeV Gamma sources.
Joern Grosse-Knetter: "Construction and Tests of Modules for the ATLAS Pixel Detector"
Abstract: The ATLAS Pixel Detector is the innermost layer of the ATLAS tracking system. It significantly contributes to the ATLAS track and vertex reconstruction and the b-tagging capabilities of ATLAS. The detector consists of 2x6 cm2 n-on-n silicon sensors, subdivided into 46080 pixels which are connected individually to 16 front-end chips via "bumps". These chips are wire-bonded to a module control chip mounted on a kapton-flex-hybrid which is glued to the back-side of the pixel sensor. The module control chip communicates with the off-detector electronics via opto-links, whereas power is fed into the chips via cables connected to the flex-hybrid.
The position of the pixel detector near the interaction point requires excellent radiation hardness, mechanical and thermal robustness, good long-term stability, all combined with a low material buget. The pre-production phase of such pixel modules has nearly finished, yielding fully functional modules. The module construction as well as results obtained with the operation of pixel modules in the lab and in test beams are presented.
Ermanno Imbergamo et al.: "Relevant Results from the NA48 Experiment"
Abstract: We report relevant results from the NA48 experiment at the CERN SPS. NA48 was proposed in 1990 to study direct CP violation in K0--> pipi to a level of accuracy sufficient to resolve the inconclusive status left by the previous measurements performed by NA31 and E731. In 2002 NA48 published the final result. Small modifications to the experimental setup have allowed NA48 to go forward with an extensive investigation of K0 rare decays and hyperon decays. Some results are already available and reported here together with the main one.
F. Mandl et al.: "New CKM-related Studies on b-Decays in the DELPHI Experiment at LEP"
Abstract: The e-e+ collider LEP, running at sqrt{s} = m(Z0), has been a copious source of b-hadrons produced in decays Z --> bb. We present recent studies using about 4 millions hadronic Z decays acquired by the DELPHI detector between 1992 and 2000. They rely on efficient particle identification, precise track and vertex reconstruction and sophisticated data analysis algorithms. Presented are: a new measurement of the CKM matrix element Vcb in the semileptonic exclusive decays B0d --> D*+ l- nu; a new measurement of the B0d barB0d oscillation frequency Delta (md); and searches by three methods for B0s -barB0s oscillations, yielding new lower limits on Delta(ms).
H Hakobyan et al.: "Investigation of preshower Detector response in the CMS Experiment"
Abstract: One of the main goals of the LHC collider at CERN is the discover of the low mass neutral Higgs boson. The Preshower is a high granularity detector located in front of the crystal Endcap calorimeter in the CMS experiment.It allows to improve the separation of real photons from background particles(neutral pions). The objective of a current work is a calculation of the Preshower detector with CMSIM package and investigation of its linear response. The preshower response is very linear for the case of single photons and linearity is becoming worse with increasing the number of initial particles.
L. Gutay: "Experimental Evidence for Deconfined Quark-Gluon Hadronic Matter in p antip Collisions at 1.8 TeV"
Abstract: We observed the formation of a new deconfined Quark-Gluon state of hadronic matter in the central plato (((( 3.5 region. Using Bjorken's 1D expansion model we conceptually break the process into three steps: in the collider coordinate system at t=0, a high initial energy density (i, high initial temperature Ti and initial entropy Si system is formed. This initial system executes a one-dimensional isentropic expansion during which it's temperature and energy density drop to a universal final values Tf and (f where the Q-G system reconfines into hadrons. We measured the deconfined hadronic volumes, 4.4 < V < 13 fm3, produced by a one-dimensional (1D) expansion. Both the expansion volume V and the energy of the deconfined system E are proportional to the charged particle pseudorapidity density dNc/d(, which we measured to be in the interval: 6.75 < dNc/d(<20.2. The hadronization temperature is Tf=179.5(5 (syst) MeV and the hadronization energy density is (f= 1.1(0.26 (stat) GeV/f3. These measured, presumably universal, reconfinement parameters correspond to an excitation of 24.8 (6.2 (stat) quark-gluon degrees of freedom and three-fold increase in the number of inelastic collisions.
Manjit Kaur: "Measurement of the Strong Coupling Constant at e+e- Annihilations at LEP"
Abstract: Results are presented from a study of the structure of high energy hadronic events recorded in L3 detector at cms energies larger than 192 GeV. The distribution of several event shape variables are calculated to resummed O(alphas2) QCD calculations. The strong coupling constant is determined at three average centre-of-mass energies. These measurements combined with previous L3 measurements at lower energies, demonstrate the running of alpha_s as exected in QCD and yield alphas(mz)= 0.1227 +- 0.0012 +- 0.0058.
M. Czakon: "Full Two Loop Electroweak Corrections to the Muon Decay Lifetime"
Abstract: The two loop fermionic corrections to the muon decay lifetime are recalculated leading to a result, which corrects the previously available value. Together with the recently evaluated bosonic part, this gives the full electroweak contribution at the two loop level.
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