114313
Baryon octet magnetic moments to all orders in flavor breaking: An application to the problem of the strangeness in the nucleon
Using the general QCD parametrization (GP) we display the magnetic moments of the octet baryons including all flavor breaking terms to any order. The hierarchy of the GP parameters allows to estimate a parameter ${g}_{0}$ related to the quark loops contribution of the proton magnetic moment; its magnitude is predicted to be inside a comparatively small interval including the value given recently by Leinweber et al. from a lattice QCD calculation.
120916653
The relation between QCD and constituent quark models
120776511
The non-relativistic quark model
The classification scheme and decay properties of hadron states are investigated in the framework of the non relativistic quark model. The main successes and the unsolved difficulties of the model are presented indicating the future work which could be done to understand and exploit the non-relativistic quark ideas.РезюмеИсследованы схема классификации и распадные свойства адронов в рамках статической модели кварков. Изложены главные успехи и нерешенные проблемы модели, указывая задачи, которые должны быть решены для лучшего понимания и использования нерелятивистских идей.
14665617
Comment on "Chiral symmetry and the intrinsic structure of the nucleon"- by D.B.Leinweber,A.W.Thomas and R.D.Young
Some remarks are presented on a recent paper (Leinweber,Thomas and Young, Phys.Rev.Lett. 86, 5011, 2001). In particular a statement of the above paper on the fact that the ratio between the magnetic moments of proton and neutron should remain constant at -3/2, independent of the change of the quark mass is discussed on the basis of the general parameterization.
119592224
New Results in the Search of Quarks in Matter by the Magnetic Levitation Electrometer
Abstract The results of many runs performed levitating in succession several spheres without opening the levitation chamber show the existence of an additional (magneto-electric) force acting on the sphere. Ignoring this force in the analysis of the data produces “spurious” fractional charges.
124837005
SEARCH FOR QUARKS WITH THE FERROMAGNETIC LEVITATION ELECTROMETER
17683309
Parasitic energy loss in the LEP superconducting cavities
The energy loss of bunches in the LEP superconducting (SC) cavities has been determined by measuring the closed orbit as a function of current with the beam position monitors located at finite dispersion. This method has already been used in earlier experiments to determine the distribution of the longitudinal impedance of different parts of LEP. In the present experiment the energy loss in two straight sections, containing only SC cavities, was compared with that in sections having both copper cavities and SC cavities. The results confirm the impedance calculations for the two types of cavities. The accuracy of the measurements was considerably improved by determining simultaneously the orbits of bunches with different currents. At the same time with these beam-based impedance measurements, the power dissipation was observed directly by local temperature monitors in different elements: the inter-cavity bellows inside the cryostat, the warm intermodule bellows, and ferrite absorbers which were installed in two places to reduce the energy leaking out of cavities. These observations were correlated with the change of cryogenics power consumption, and showed an unexpected dependence of energy loss on beam energy.
55091650
Betatron function measurement at LEP using the BOM 1000 turns facility
A new method for measuring the beta function around LEP is presented. The method uses phase difference measurements between three adjacent beam position monitors to obtain the value for the beta function at the monitors and in their neighbourhood, e.g. at interaction points, electrostatic separators etc. The phase differences are obtained from measuring coherent betatron oscillations for 1024 turns at the 504 beam position monitors. After a discussion of the accuracy of the method the measured values for the beta function are compared with the theoretical values for different lattices. In regular parts of the lattice (e.g. arcs) the beating of the beta function measured using this method agrees well with the beating obtained by another method using a fit of the phase over 15 monitors.<<ETX>>
119009661
Determination of coupled-lattice properties using turn-by-turn data
A formalism for extracting coupled betatron parameters from multiturn, shock excited, beam position monitor data is described. The most important results are nonperturbative in that they do not rely on the underlying ideal lattice model. Except for damping, which is assumed to be exponential and small enough to be removed empirically, the description is symplectic. As well as simplifying the description, this leads to self-consistency checks that are applied to the data. The most important of these is a {open_quotes}magic ratio{close_quotes} of Fourier coefficients that is required to be a lattice invariant, the same at every beam position monitor. All formulas are applied to both real and simulated data. The real data was acquired June, 1992 at LEP as part of decoupling studies, using the LEP beam orbit measurement system. Simulated data, obtained by numerical tracking (TEAPOT) in the same (except for unknown errors) lattice, agrees well with real data when subjected to identical analysis. For both datasets, deviations between extracted and design parameters and deviations from self-consistency can be accounted for by noise and signal processing limitations. This investigation demonstrates that the LEP beam position system yields reliable local coupling measurements. It can be conservatively assumed that systems of similar design at the SSC and LHC will provide the measurements needed for local decoupling.
36021315
The detector safety system for LHC experiments
The Detector Safety System (DSS), currently being developed at CERN under the auspices of the Joint Controls Project (JCOP), will be responsible for assuring the protection of equipment for the four Large Hadron Collider (LHC) experiments. Thus, the DSS will require a high degree of both availability and reliability. After evaluation of various possible solutions, a prototype is being built based on a redundant Siemens PLC front-end, to which the safety-critical part of the DSS task is delegated. This is then supervised by a PVSS SCADA system via an OPC server. The PLC front-end is capable of running autonomously and of automatically taking predefined protective actions whenever required. The supervisory layer provides the operator with a status display and with limited online reconfiguration capabilities. Configuration of the code running in the PLCs will be completely data driven via the contents of a "configuration database." Thus, the DSS can easily adapt to the different and constantly evolving requirements of the LHC experiments during their construction, commissioning, and exploitation phases.
61569699
The RTC-a software support system for the control of the CERN SPS
The RTC (Run Time Coordinator) is described. It is a software support system designed for the SPS (Super Proton Synchrotron) control system to provide a run time environment for application software. It coordinates the execution of individual programs or processes and supervises the process control, i.e. process synchronization, interprocess communication, data transfer, and operator I/O (input/output). This supervision includes the control of processes distributed on a Unix-based network. A standard language independent data interface is part of the system. The system includes tools for data presentation, error logging, and contention resolution. Separating system-dependent features for the body of the application programs leads to high flexibility and simplifies the software development. The basic philosophy of the RTC is discussed and its implementation is described.<<ETX>>