Particle states of Lattice QCD

We determine the degeneracy factor and the average particle mass of particles that produce the Lattice QCD pressure and specific entropy at zero baryon chemical potential. The number of states of the gluons and the quarks are found to converge above $T=$230 MeV to almost constant values, close to the number of states of an ideal Quark-Gluon Phase, while their assigned masses retain high values. The number of states and the average mass of a system containing quarks in interaction with gluons are found to decrease steeply with increase of temperature between $T \sim 150$ and 160 MeV, a region contained within the region of the chiral transition. The minimum value of the number of states within this temperature interval indicates that the states are of hadronic nature.Comment: 21 pages, 18 figure

The strange-quark chemical potential as an experimentally accessible "order parameter" of the deconfinement phase transition for finite baryon-density

We consider the change of the strange-quark chemical potential in the phase diagram of nuclear matter, employing the Wilson loop and scalar quark condensate order parameters, mass-scaled partition functions and enforcing flavor conservation. Assuming the region beyond the hadronic phase to be described by massive, correlated and interacting quarks, in the spirit of lattice and effective QCD calculations, we find the strange-quark chemical potential to change sign: from positive in the hadronic phase - to zero upon deconfinement - to negative in the partonic domain. We propose this change in the sign of the strange-quark chemical potential to be an experimentally accessible order parameter and a unique, concise and well-defined indication of the quark-deconfinement phase transition in nuclear matter.Comment: 22 pages, 14 figures within text, 2 figures(6,B3) as separate files. To be published in J.Phys.G: Nucl.&Part.Phys. G28 (2002

Model of Centauro and strangelet production in heavy ion collisions

We discuss the phenomenological model of Centauro event production in relativistic nucleus-nucleus collisions. This model makes quantitative predictions for kinematic observables, baryon number and mass of the Centauro fireball and its decay products. Centauros decay mainly to nucleons, strange hyperons and possibly strangelets. Simulations of Centauro events for the CASTOR detector in Pb-Pb collisions at LHC energies are performed. The signatures of these events are discussed in detail.Comment: 19 pages, LaTeX+revtex4, 14 eps-figures and 3 table

Physics at Very Small Angles with CASTOR at CMS

CASTOR is a small (56 cm diameter) quartz-tungsten Cerenkov calorimeter covering the small angles 0.2-0.6 deg (5.2<="eta"<=6.4) in CMS, a major experiment at the LHC. Particularly with heavy-ion reactions a substantial fraction of the total reaction energy goes into this large "eta" region. CASTOR will function as a part of CMS and also as an independent detector to search for special types of events in the far-forward region. It is divided into 16 azimuthal sectors, each with 18 longitudinal segments to allow identification of particles by their energy-loss profiles. The most forward segments are smaller to better characterize electromagnetic events

Performance Studies of Prototype II for the CASTOR forward Calorimeter at the CMS Experiment

We present results of the performance of the second prototype of the CASTOR quartz-tungsten sampling calorimeter, to be installed in the very forward region of the CMS experiment at the LHC. The energy linearity and resolution, as well as the spatial resolution of the prototype to electromagnetic and hadronic showers are studied with E=20-200 GeV electrons, E=20-350 GeV pions, and E=50,150 GeV muons from beam tests carried out at CERN/SPS in 2004. The responses of the calorimeter using two different types of photodetectors (avalanche photodiodes APDs, and photomultiplier tubes PMTs) are compared.Comment: 16 pages, 22 figs., submitted to EPJ-

Breakdown Resistance Analysis of Traction Motor Winding Insulation under Thermal Ageing

Stator inter-turn faults are among the most important electric motor failures as they progress fast and lead to catastrophic motor breakdowns. Inter-turn faults are caused due to the windings’ insulation degradation. The main stress which deteriorates the insulation is the thermal one. Proper understanding of how this stress influences the electrical properties of insulation over time may lead to reliable prognosis and estimation of the motor’s remaining useful life. In transport applications where reliability and safety come first it is a critical issue. In this paper, extensive experimental testing and statistical analysis of thin film insulation for traction motor windings has been performed under fixed thermal stress. The results indicate that for high thermal stress the electrical properties of the insulation material present a non-monotonic behavior thus proving the well-known and established Arrhenius law inadequate for modelling this type of problems and estimating the remaining useful life of thin film insulation materials