QCD Phase Transitions, Volume 15 (open access)

QCD Phase Transitions, Volume 15

The title of the workshop, ''The QCD Phase Transitions'', in fact happened to be too narrow for its real contents. It would be more accurate to say that it was devoted to different phases of QCD and QCD-related gauge theories, with strong emphasis on discussion of the underlying non-perturbative mechanisms which manifest themselves as all those phases. Before we go to specifics, let us emphasize one important aspect of the present status of non-perturbative Quantum Field Theory in general. It remains true that its studies do not get attention proportional to the intellectual challenge they deserve, and that the theorists working on it remain very fragmented. The efforts to create Theory of Everything including Quantum Gravity have attracted the lion share of attention and young talent. Nevertheless, in the last few years there was also a tremendous progress and even some shift of attention toward emphasis on the unity of non-perturbative phenomena. For example, we have seen some efforts to connect the lessons from recent progress in Supersymmetric theories with that in QCD, as derived from phenomenology and lattice. Another example is Maldacena conjecture and related development, which connect three things together, string theory, super-gravity and the (N=4) supersymmetric gauge …
Date: March 20, 1999
Creator: Schaefer, T. & Shuryak, E.
Object Type: Article
System: The UNT Digital Library
Initial State Temperature and Degrees of Freedom in SPS A+A Collisions (open access)

Initial State Temperature and Degrees of Freedom in SPS A+A Collisions

A dramatic rise in the heat capacity <font face="symbol">e</font>T<sup>4</sup> of high-temperature nuclear/QGP matter has been a long-standing prediction in high-energy heavy-ion physics, but is difficult to verify directly. Initial-state energy densities, measured through calorimetery, and limits on initial-state temperature, inferred through measurement of high-P<sub>T</sub> direct photons, can be combined to provide a nearly model-independent lower limit on the beat capacity of initial-state matter in A+A collisions at the CERN-SPS. This is the most direct evidence to date for the rise in the heat capacity, and the implied new degrees of freedon, in high-temperature nuclear matter.
Date: March 20, 1999
Creator: Stankus, P.
Object Type: Article
System: The UNT Digital Library
Measurement of the Electron Affinities of Indium and Thallium (open access)

Measurement of the Electron Affinities of Indium and Thallium

The electron affinities of indium and thallium were measured in separate experiments using the laser-photodetachment electron spectroscopy technique. The measurements were performed at the University of Nevada, Reno. Negative ion beams of both indium and thallium were extracted from a cesium-sputter negative ion source, and mass analyzed using a 90{sup o} bending magnet. The negative ion beam of interest was then crossed at 90{sup o} with a photon beam from a cw 25-Watt Ar{sup +} laser. The resulting photoelectrons were energy analyzed with a 160{sup o} spherical-sector spectrometer. The electron affinity of In({sup 2}P{sub 1/2}) was determined to be 0.404 {+-} 0.009 eV and the electron affinity of thallium was determined to be 0.377 {+-} 0.013 eV. The fine-structure splittings in the ground states of the negative ions were also determined. The experimental measurements will be compared to several recent theoretical predictions.
Date: March 20, 1999
Creator: Thompson, J. S.; Carpenter, D. L.; Covington, A. M.; Williams, W. W.; Kvale, T. J. & Seely, D. G.
Object Type: Article
System: The UNT Digital Library
PARTON SATURATION, PRODUCTION, AND EQUILIBRATION IN HIGH ENERGY NUCLEAR COLLISIONS (open access)

PARTON SATURATION, PRODUCTION, AND EQUILIBRATION IN HIGH ENERGY NUCLEAR COLLISIONS

Deeply inelastic scattering of electrons off nuclei can determine whether parton distributions saturate at HERA energies. If so, this phenomenon will also tell us a great deal about how particles are produced, and whether they equilibrate, in high energy nuclear collisions.
Date: March 20, 1999
Creator: Venugopalan, R.
Object Type: Article
System: The UNT Digital Library
Manufacturable CuIn(Ga)Se{sub 2}-based solar cells via development of co-sputtered CuInSe{sub 2} absorber layers (open access)

Manufacturable CuIn(Ga)Se{sub 2}-based solar cells via development of co-sputtered CuInSe{sub 2} absorber layers

Yield and reproducibility remain issues in CuIn(Ga)Se{sub 2} (CIGS) photovoltaic module fabrication. While small-area cells (&lt;1 cm{sup 2}) over 18% efficient have been reported, the best large-area manufactured devices (&gt;1 ft{sup 2}) are 11% efficient with about 60% yield. If improvements in large-area manufacturing can accomplish 15% efficiency and 90% yield, the result is a doubling in throughput leading to a reduction in cost per watt of over 50%. The challenge now facing the photovoltaics industry is to bring the efficiencies of small-area cells and large-area industrial modules closer together and to raise manufacturing yields.
Date: March 20, 1999
Creator: Eisgruber, Dr. Ingrid
Object Type: Report
System: The UNT Digital Library