Finite Temperature Meson Correlation Functions in HTL Approximation

We calculate temporal correlators and their spectral functions with meson quantum numbers in the deconfined phase of QCD using the hard thermal loop (HTL) approximation for the quark propagator. Although this approach does not result in a complete next-to-leading order perturbative calculation it takes into account important medium effects such as thermal quark masses and Landau damping in the quark-gluon plasma. We show that both effects lead to competing modifications of the free mesonic correlation functions. We find that correlators in scalar channels are only moderately influenced by the HTL medium effects, while the HTL-vertex corrections lead to divergent vector correlators.Comment: 14 pages, LaTeX2e File, 8 EPS-files, minor changes in abstract and text, to appear in Phys. Lett.

Brief Note: Morphological Variations of Cambarus (Cambarus) bartonii cavatus (Decapoda: Cambaridae) from Ohio, With a Diagnosis of the Ohio Form

Author Institution: Department of Zoology, The Ohio State Universit

An Illustrated Key to the Ohio Cambarus and Fallicambarus (Decapoda: Cambaridae) with Comments and a New Subspecies Record

Author Institution: Department of Zoology, The Ohio State UniversityAn illustrated taxonomic key is presented using structures of the chela and carapace to identify the 4 species and 2 subspecies of Cambarus, and one species of Fallicambarus known to occur in Ohio. Those forms broadly distributed throughout the state are C. (Lacunicambarus) diogenes diogenes Girard, a primary or secondary burrower; and C. (Cambarus) bartonii cavatus Hay, a secondary or tertiary burrower; the latter crayfish has not been previously recorded from the state. Species with restricted distributions are C. (C.) ortmanni Williamson, a primary or secondary burrower confined to the Ordovician region of southwestern Ohio; C. (C.) sciotensis Rhoades, a stream dweller occurring in the Scioto River, Little Scioto River, and tributaries of the Ohio River in Scioto and Lawrence counties; C. (C.) b, carinirostris Hay, a secondary or tertiary burrower frequenting streams of the Flushing Escarpment, Mahoning River, and Grand River drainages in eastern and northeastern Ohio; C. (Puncticambarus) robustus Girard, a stream inhabitant occupying primarily tributaries to Lake Erie and central and northern tributaries to the Ohio River, and F. (Creaserinus) fodiens (Cottle), a primary burrower occurring chiefly in the glaciated regions of northern Ohio. Species with broad distributions generally have a larger number of species as associates than those with restricted distributions

Damping Rate of a Hard Photon in a Relativistic Plasma

The damping rate of a hard photon in a hot relativistic QED and QCD plasma is calculated using the resummation technique by Braaten and Pisarski.Comment: 4 pages, REVTeX, 2 figures (not included), UGI-MT-94-0

Multiparticle production in the Glasma at NLO and plasma instabilities

We discuss the relation between multi-particle production in the Glasma at next-to-leading order and the physics of plasma instabilities.Comment: 4 pages, talk at Quark Matter 200

Field Theoretic Description of Ultrarelativistic Electron-Positron Plasmas

Ultrarelativistic electron-positron plasmas can be produced in high-intensity laser fields and play a role in various astrophysical situations. Their properties can be calculated using QED at finite temperature. Here we will use perturbative QED at finite temperature for calculating various important properties, such as the equation of state, dispersion relations of collective plasma modes of photons and electrons, Debye screening, damping rates, mean free paths, collision times, transport coefficients, and particle production rates, of ultrarelativistic electron-positron plasmas. In particular, we will focus on electron-positron plasmas produced with ultra-strong lasers.Comment: 13 pages, 7 figures, 1 table, published versio

The Quark-Gluon-Plasma Liquid

The quark-gluon plasma close to the critical temperature is a strongly interacting system. Using strongly coupled, classical, non-relativistic plasmas as an analogy, we argue that the quark-gluon plasma is in the liquid phase. This allows to understand experimental observations in ultrarelativistic heavy-ion collisions and to interpret lattice QCD results. It also supports the indications of the presence of a strongly coupled QGP in ultrarelativistic heavy-ion collisions.Comment: 8 pages, 2 figures, final version, to bepublished in J. Phys.

Elastic and thermodynamic properties of the shape-memory alloy AuZn

The current work reports on the elastic shear moduli, internal friction, and the specific heat of the B2 cubic ordered alloy AuZn as a function of temperature. Measurements were made on single-crystal and polycrystalline samples using Resonant Ultrasound Spectroscopy (RUS), semi-adiabatic calorimetry and stress-strain measurements. Our results confirm that this alloy exhibits the shape-memory effect and a phase transition at 64.75 K that appears to be continuous (second-order) from the specific heat data. It is argued that the combination of equiatomic composition and a low transformation temperature constrain the chemical potential and its derivatives to exhibit behavior that lies at the borderline between that of a first-order (discontinuous) and a continuous phase transition. The acoustic dissipation does not peak at the transtion temperature as expected, but shows a maximum well into the low-temperature phase. The Debye temeprature value of 219 K, obtained from the low-temperature specific heat data is in favorable agreement with that determined from the acoustic data (207 K) above the transition.Comment: 25 pages, 6 figures, submitted to Phys. Rev.