117874201
First Results from the TOTEM Experiment
Visitor from an external Institution.The ﬁrst physics results from the TOTEM experiment are here reported,concerning the measurements of the total, diﬀerential elastic, elastic and in-elastic pp cross-section at the LHC energy of√s = 7 TeV, obtained using theluminosity measurement from CMS. A preliminary measurement of the forwardcharged particle η distribution is also shown.PRESENTED AT
121853587
Predictions on the total cross-section and real part at LHC and SSC
Abstract An overall fit to the data on the total cross section and on the real part of the forward amplitude for p p and pp was performed using dispersion relations. The energy dependence of the total cross section was studied up to s = 100 TeV . Numerical predictions are presented for LHC and SSC energies.
122588297
Elastic partial-wave amplitude and poles of higher order
Starting from the usual formula for the elastic partial-wave scattering amplitude a new formal decomposition of the phase shift is given which leads to a new more general expression for energy-dependence exhibiting poles of higher order. This decomposition is in agreement with a multichannel decay model of unstable particles, which stands behind this approach.
44874120
Momentum-transfer dependence of the elastic-amplitude phase in high-energy hadron scattering.
The phase of the elastic-scattering amplitude is responsible for the probability distribution of events in the impact-parameter space. A rather steep increase of it around t = 0 can lead to a peripheral behavior of elastic collisions. The experimental data from the interference regions of hadronic and Coulomb scatterings have been shown to be fully consistent with such a peripherality. Other reasons supporting peripherality have been mentioned, also.
119975839
Impact parameter structure derived from elastic collisions
Impact parameter profiles derived from elastic scattering data within the framework of standard model cannot be regarded as definite being burdened by two defficiences: influenced strongly by an a priori (physically non-reasoned) assumption and by non-unique relation to elastic hadron amplitude. A mathematically consistent general model providing a unique relation is presented and some new formulas allowing to evaluate mean-square values of corresponding impact parameters (for elastic and inelastic processes directly from the t dependent amplitude) are introduced. Critical arguments against the mentioned a priori assumption are discussed as well.
122290860
The unstable system withN states and the propagator matrix with a pole of higher order
Starting from the general quantum-mechanical laws, the general form of the mass-matrix for a special unstable system withN states and of the propagator with higher order pole is derived.
110037616
The results of mass testing of the plastic streamer tubes for the DELPHI hadron calorimeter
Abstract The procedure and results of mass testing of plastic streamer tubes for the DELPHI hadron calorimeter are described in detail. The mass testing includes three stages: high voltage test and conditioning, X-ray test on radiation load capability and wire tension control in ready detectors. The productivity of the test workshop was 240 detectors per day at maximum. After testing of about 25 000 streamer tubes, 8% have been rejected on the ground of severe rejection criteria which exceed significantly the working conditions in the DELPHI experiment.
186674866
The First Three TILECAL Submodule Assembly in Prague
120268916
Experimental tests of neutron shielding for the ATLAS forward region
Abstract Experimental tests devoted to the optimization of the neutron shielding for the ATLAS forward region were performed at the CERN-PS with a 4 GeV/ c proton beam. Spectra of fast neutrons, slow neutrons and gamma rays escaping a block of iron (40×40×80 cm 3 ) shielded with different types of neutron and gamma shields (pure polyethylene – PE; borated polyethylene – BPE; lithium filled polyethylene – LiPE; lead; iron) were measured by means of plastic scintillators, a Bonner spectrometer, a HPGe detector and a slow neutron detector. Effectiveness of different types of shielding against neutrons and γ-rays were compared. The idea of a segmented outer layer shielding (iron, BPE, iron, LiPE) for the ATLAS forward region was also tested.
59500704
JINR (Dubna) and Prague Tier2 sites: Common experience in the WLCG grid infrastructure
The paper describes the cooperation of JINR specialists and Czech colleagues in the field of deployment and development of modern grid technologies within the framework of the WLCG global infrastructure project. Special attention is paid to the development and usage of monitoring systems.
121692314
Test of a compact Si-strip detector for the forward region in DELPHI
Abstract The DELPHI detector will be upgraded by a new silicon detector in the very forward region to fulfil the physics demands of the LEP200 program. This detector will cover the angular region between 10° and 25° with respect to the beam pipe and will have a two dimensional readout. The severe space restrictions in this region lead us to develop a new arrangement of detectors and electronic hybrids. In beam tests the layout of the detectors was optimised. Special attention was given to the charge loss in intermediate strips for detectors with large strip pitch. Beam test results obtained with different detector layouts, e.g. various implant widths, and different angle of the incident particles will be shown.