116487099
The trace of the energy momentum tensor and the lattice interaction measure at finite temperature
6925871
The effects of coloured quark entropy on the bag pressure
We study the effects of the ground state entropy of coloured quarks upon the bag pressure at low temperatures. The vacuum expectation values of the quark and gluon fields are used to express the interactions in the QCD ground state in the limit of low temperatures and chemical potentials. Apparently, the inclusion of this entropy in the equation of state provides the hadron constituents with an additional heat which causes a decrease in the effective latent heat inside the hadronic bag and consequently decreases the non-perturbative bag pressure. We have considered two types of baryonic bags, Δ and Ω−. In both cases we have found that the bag pressure decreases with the temperature. On the other hand, when the coloured quark ground state entropy is not considered, the bag pressure as conventionally believed remains constant for finite temperature.
115316476
Limiting particle density of a relativistic Fermi gas in a magnetic field
On etudie la densite totale de particules dans l'ensemble grand canonique d'un gaz de Fermi relativiste constitue de particules de spins 1/2 en presence d'un champ magnetique externe homogene constant
118943299
THE PHYSICAL PHASE OF DIMENSIONALLY REDUCED GAUGE-THEORIES
We investigate the relationship between the high-temperature deconfined phase of the SU(2) gauge theory to the phases of the corresponding three-dimensional adjoint Higgs model. For various temperatures we simulate the effective theory in a neighbourhood of the physical states, that is of those values of the coupling constants that describe the infrared behaviour of the four-dimensional theory and which have been calculated by applying dimensional reduction techniques. We show that the physical points belong to the confined phase of the SU(2) adjoint Higgs model.
18890188
The speed of sound in hadronic matter
We calculate the speed of sound cs in an ideal gas of resonances, whose mass spectrum is assumed to have the Hagedorn form ρ(m)∼m−aexp {bm}, which leads to singular behavior at the critical temperature Tc=1/b. With a=4 the pressure and the energy density remain finite at Tc, while the specific heat diverges there. As a function of the temperature, the corresponding speed of sound initially increases similarly to that of an ideal pion gas, until near Tc resonance effects dominate, which causes cs to vanish as (Tc−T)1/4. In order to compare this result to the physical resonance gas models, we introduce an upper cut-off M in the resonance mass integration. Although the truncated form still decreases somewhat in the region around Tc, the actual critical behavior in these models is no longer present.
116060740
THERMODYNAMICS OF A RELATIVISTIC FERMI GAS IN A STRONG MAGNETIC-FIELD
On etudie les proprietes thermodynamiques dans l'ensemble grand canonique pour un gaz ideal de spins-Y 2 relativiste contenant a la fois particules et antiparticules en presence d'un champ magnetique constant fort
9113100
Parameter optimization for the low frequency linacs in the NLC
In the present Next Linear Collider (NLC) design, S and L-band linacs are used to accelerate the beams to 10 GeV, where they are injected into the main X-band linacs. As injectors for the main accelerator, these linacs are required to deliver clean beams while being reliable and cost effective. These requirements set stringent tolerances on the design of the accelerators. There are two types of misalignment tolerances that are of great concern: cell-to-cell and structure-to-structure tolerances, which are dominated by long- and short-range wakefield effects, respectively. For a given lattice design, the structure-to-structure tolerance (which has strong impacts on girder configurations) is mainly determined by the global parameters such as the average iris size, the length and the type of the structure. This paper will discuss the optimization of the structure parameters to allow looser structure-to-structure tolerances; the cell-to-cell tolerance is related to the details of the single structure design and will not be addressed here. The optimization described here was based on a cost model for NLC and a wakefield scaling law for the tolerance estimations.
187201784
An Assembly Procedure for Drift Tube Chambers
120049678
Strength of the antineutrino-proton neutral-current interaction
Using the Fermilab 15-foot hydrogen bubble chamber exposed to a broad-band $\overline{\ensuremath{\nu}}$ and $\ensuremath{\nu}$ beam, we have studied the neutral-to-charged-current cross-section ratio $R$ for interactions on protons. The ratio ${R}^{\overline{\ensuremath{\nu}}p}$ is found assuming various forms of the neutral-current couplings. The data are consistent with the predictions of the Weinberg-Salam model and, assuming this model, we obtain ${R}^{\overline{\ensuremath{\nu}}p}=0.42\ifmmode\pm\else\textpm\fi{}0.13$.
108681531
A 2-MeV microwave thermionic gun
A high-gradient, S-band microwave gun with a thermionic cathode is being developed in a collaborative effort by AET, Varian, and SSRL. A prototype design using an upgraded Varian dispenser cathode mounted with thermal isolation directly in the first half-cell of a 1-1/2 cell, side-coupled, standing-wave cavity has been fabricated and is being tested. Optimization of the cavity shape and beam formation was done using SUPERFISH, MASK, and PARMELA. An overview of design details, as well as the status of in-progress beam tests, will be presented. 9 refs., 6 figs.
123045321
Evidence for local compensation of transverse momentum in pp collisions at 200 and 300 GeV/c
Evidence is presented for local compensation of transverse momentum in pp collisions at 200 and 300 GeV/c. The data are compared with a model which contains no dynamical transverse-momentum correlations. These data are used to determine a lower bound on the slope of the Pomeranchuk trajectory. (AIP)