There has been a recent growth in our faculty doing research at high energy accelerators. The newer additions include Prof. Andrew Lankford, who works with the D0 detector at Fermilab that co-discovered the top quark, at the Beijing electron-positron collider (BES), at the SLAC B factory, and with the ATLAS detector for the LHC. They also include Prof. William Molzon, who searches to verify new aspects of the weak interactions in higher order weak processes and for new physics in extremely rare K meson decays at the Brookhaven National Laboratory. These new group leaders have also added postdoctoral fellows, graduate students, and research physicists. Of the more senior faculty, Profs. Jonas Schultz and Mark Mandelkern have undertaken new experiments in charm quark mesons and anti-hydrogen at Fermilab, and at the Beijing high intensity electron-positron collider (BES). They are also part of the SLAC B factory (BABAR) collaboration.
U. C. Irvine also has a large and distinguished array of non-accelerator based elementary particle experimental research programs. The advances made in detection techniques of extra-terrestrial elementary particle phenomena, as for example the incredible observation of neutrinos from the Supernova 1987A by the Irvine-Michigan-Brookhaven detector, have opened astro-particle ``labs''of extreme energy, density and particle content for understanding new areas of particle physics not accessible to laboratory experiment.
The astro-particle experimental group has also grown recently with the addition of Prof. Gaurang Yodh, who works on CYGNUS and MILAGRO cosmic ray pointing experiments at the Los Alamos National Laboratory and on AMANDA. The other addition, Prof. Steve Barwick, is a leader in balloon cosmic ray experiments for NASA, on the Polar NSF program AMANDA for deep ice neutrino detection, and with MILAGRO.
The proton decay, solar neutrino, dark matter, atmospheric neutrino, and supernova detector group founded by Emeritus Prof. Fred Reines, and now led by Professor in Residence Henry Sobel and Research Professors William Kropp, Leroy Price, and Wojciech Gajewski, are now participating in Super-Kamiokanda, which has an order of magnitude increase in detection capability in these areas and will turn on in 1996.
New collaborations in reactor neutrino oscillation experiments in France have been started. The groundbreaking double beta decay detection by Research Professor Mike Moe have been continued to new nuclei and have set important limits on neutrino properties and conjectured Majorana neutrinos which are their own antiparticles, and Majoron bosons. Prof. Riley Newman has led in important gravity and fifth force experiments. These distinguished researchers have established UC Irvine as a world leader in the field of non-accelerator elementary particle experiment.
There are a total of about 40 particle experimenters at U. C. Irvine, including graduate students, postdoctoral researchers, and research professors in addition to the faculty. The program has attracted very substantial extramural funds for the support of research and graduate student research assistants.
Although the experimental results and the theories tested by them in this high energy program have no immediate applications, they help to build the basic knowledge on which future discoveries, inventions and developments will be based. In addition, students trained in these techniques go on to contribute centrally to important practical developments and applications. High energy students and practitioners have made important contributions in computer science, data reduction and analysis, scanning, and computer simulation techniques. These have led to seminal contributions and applications in areas as diverse as national defense and medical science (e.g., medical imaging). The work leading to higher energy accelerators has given a tremendous boost to the development of large scale applications of superconductivity. Indeed, the training of students in particle physics yields very significant direct and indirect benefits with regard to national needs.
Elementary Particle Theory
Professor Myron Bander: formulation of lattice (simplicial) quantum gravity; statistical mechanics and field theory; electroweak theory. He has twice served as Department Chair and has served as Dean of Physical Sciences.
Professor Herbert Hamber: quantum and statistical field theory, lattice Quantum Chromodynamics, perturbative and non-perturbative (lattice) gravity.
Professor Dennis Silverman: electroweak theory and $CP$ violation, including $B$ factory experiments, new physics models, and relativistic bound state equations for hadrons.
Two theory faculty have retired but pursue active research. Professor Emeritus Meinhard Mayer: mathematical physics, geometrical methods in field theory, development of a symbolic computing environment for mathematical physics, and wavelet analysis.
Professor Emeritus Gordon Shaw: studies of strange quark matter and searches for free quarks, models of neural networks, and effects of musical training on learning.
Our Ph. D. students have gone into faculty positions or positions with national laboratories, medical facilities, or the computer industry. The faculty in particle theory have instituted innovative courses in computational physics and in symbolic algebra on the computer. They teach a two quarter sequence in field theory (advanced quantum mechanics), and share teaching a three quarter graduate sequence in particle physics. They also teach courses in group theory and general relativity, in addition to the regular graduate and undergraduate courses.
Condensed matter physics has been, and is continuing to be, the major source of innovative high technology. Among the major technological devices so obtained are the transistor, solid state lasers, fiber optics, electro- and acousto-optics, liquid crystals, light emitting and detecting diodes, superconductivity, radiation sensors, surface catalysis, integration circuits, solid state memories, optical discs, magnetic tapes and discs.
The research activities of the Condensed Matter Experimental Research Group covers a broad spectrum of topics of importance to the scientific and technological needs of the country.
Among the research activities of our group (Bron, Hopster, Parker, Rutledge, Taborek), the following are specifically cited in "Physics Through the 1990's -- Scientific Interfaces and Technological Application," published by National Academy of Sciences; in alphabetical order: acoustic waves, amorphous semiconductors, ballistic transport, coherent detection, condensed matter physics, crystal growth, electron transport, electron-electron loss spectroscopy, electron-hole plasma, grain boundaries, interface probes, interfaces, Langmuir-Blodgett films, laser physics, laser pulses (ultrashort), laser science, laser spectroscopy, lasers (mode locked), lasers (YAG), LEED, light emitting diodes, low temperature physics, magnetic optics recording, magnetic recording, magnetic resonance, metallic glasses Raman scattering, scanning tunneling microscopes, semiconductor physics, superconductivity, surface probes, surfaces, theory and modeling.
To achieve some of its goals the condensed matter group participates centrally and actively in the Institute for Surface and Interface Science (ISIS), which is an Organized Research Unit of the University of California.
An example of an exciting new program in experimental condensed matter re-search is that of Taborek and Rutledge, whose research spans a wide range from fundamental studies of phase transitions in quantum liquids to applied materials science and from processes near absolute zero, to high temperature flames and plasmas.
The growth of a film of one material on a substrate of a different material is a phenomenon known as wetting; understanding the wetting behavior of an interface is a fundamental problem in statistical physics and also of widespread practical importance. Taborek and Rutledge have recently discovered the first example of a new type of growth mode known as prewetting transition with superfluidity and solidification.
Recent exciting developments in materials science include the development of vapor phase methods of growing diamond films, and the discovery of a new phase of carbon, C60. Ongoing projects in Taborek's lab include the development of diagnostics for plasma jet deposition of diamond films, development of thermal and electrical characterization techniques for diamond and amorphous carbon, and the development of high current carbon ion beams based on plasmas generated from C60 vapor.
A collaboration of UCI faculty was recently funded (at the level of $700K/yr) to study metastable forms of doped solid hydrogen for possible use as a high energy density storage medium. Important issues in this work include the surface dynamics, sticking and growth mechanism of solid hydrogen, which is the most quantum mechanical solid. Techniques for doping hydrogen with energetic species using ion beams, and characterizing the resulting material using optical and thermal probes are under development.
The condensed matter theory group is involved in studies ranging from Superconductivity and magnetism to light scattering from random surfaces. White and Yu are studying the superconducting and magnetic properties of strongly correlated electron systems using numerical techniques. Yu is also working on properties of disordered systems, such as glasses. Dzyaloshinskii analyzes chaotic behavior in atoms in a strong magnetic field, while Mills studies the magnetic and scattering properties of this films. Maradudin's research examines enhanced backscattering of electromagnetic waves from random surfaces. Wallis is using first principles calculations to study surface phonon dispersion curves in metals.
Controlled thermonuclear fusion is an active interest of this group, involving both inertial and magnetic confinement fusion. There is an experimental program in inertial fusion with high density pinches, based on about 20 years of experience in this field. There is also an effort in magnetic confinement involving plasmas where almost all of the ions have high energy and their dynamics is therefore non-adiabatic. A strong theoretical effort exists at the present time (Rostoker, Chen) in this area.
Experimental work being pursued on fusion by Heidbrink includes research on two of the largest magnetic fusion facilities in the United States, the DIII-D tokamak in San Diego and the TFTR tokamak at Princeton University. Measurement of the transport of fast ions induced by plasma instabilities is one major area. Studies of confinement of fusion products in DIII-D, and the diffusion of deuterium and tritium beam ions in TFTR are part of this program.
Basic studies of plasma transport phenomena, diffusion and convection, including studies of nonlinear effects and turbulence, are pursued on campus by McWilliams (see McWilliams' Plasma Laboratory homepage) and Rynn using plasmas produced in the laboratory.
Work on the technology of particle beams has previously included several pro-grams on advanced accelerators. Currently there are experiments on high brightness elec-tron beam sources and intense pulsed sources of negative ions from which intense neutral beams can be made.
The above projects provide training for students in plasma, laser and accelerator physics for students who are preparing to address national needs in applied science im-mediately after getting their degrees.
The space-plasma/astrophysics theory group (Van Hoven, Chen) is engaged in research devoted to understanding basic plasma physics processes, with an emphasis on the processes underlying solar activity, such as solar flares and prominences, coronal heating and mass ejections, and the solar wind. Via high speed networks, we use supercomputers at the San Diego Supercomputer Center and at the National Magnetic Fusion Energy Computer Center. In the fall we will also begin using the newly acquired campus mini- supercomputer.