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Bit-string physics: A novel theory of everything

Description: We encode the quantum numbers of the standard model of quarks and leptons using constructed bitstrings of length 256. These label a grouting universe of bit-strings of growing length that eventually construct a finite and discrete space-time with reasonable cosmological properties. Coupling constants and mass ratios, computed from closure under XOR and a statistical hypothesis, using only {h_bar}, c and m{sub p} to fix our units of mass, length and time in terms of standard (meterkilogram-second) metrology, agree with the first four to seven significant figures of accepted experimental results. Finite and discrete conservation laws and commutation relations insure the essential characteristics of relativistic quantum mechanics, including particle-antiparticle pair creation. The correspondence limit in (free space) Maxwell electromagnetism and Einstein gravitation is consistent with the Feynman-Dyson-Tanimura ``proof.``
Date: August 1, 1994
Creator: Noyes, H.P.
Partner: UNT Libraries Government Documents Department

Neutrino interactions in the deuterium-neon 14 foot double bubble chamber

Description: We propose to study the interactions of high energy neutrinos in the 14 foot bubble chamber. The target chamber to be filled with Deuterium and the surrounding region filled with nearly pure Neon. An exposure of one million pictures is requested, in order to map out the s and t dependences of the basic interaction in which neutrinos participate.
Date: June 1, 1970
Creator: Barnes, V.E.; Carmony, D.D.; Christian, R.S.; Gaidos, J.; Garfinkel, A.F.; Gutay, L.J. et al.
Partner: UNT Libraries Government Documents Department

Searches for very rare decays of kaons

Description: The physics motivation for searches for very rare kaon decays, either forbidden or suppressed within the Standard Model, is briefly discussed. Simple arguments conclude that such searches probe possible new forces at a 200 TeV mass scale or constitute a precision test of the electroweak model. The examples of such processes are decays of K{sub L}{sup O}{yields}{mu}{sup {plus_minus}}e{sup {minus_plus}}, K{sup {plus}}{yields}{pi}{sup {plus}}{mu}{sup {plus}}e{sup {minus}}, K{sub L}{sup O}{yields}{mu}{sup {minus}}, and K{sup {plus}}{yields}{pi}{sup {plus}}{nu}{bar {nu}}. We present the current experimental status and describe the new efforts to reach sensitivities down to 1 part in 10{sup 12}. The discussion is focused on the experimental program at the Alternating Gradient Synchrotron at Brookhaven National Laboratory, where intense beams make such studies possible.
Date: December 1995
Creator: Lang, K.
Partner: UNT Libraries Government Documents Department

Gauge boson mass without a Higgs field: a simple model

Description: A simple, anomaly-free chiral gauge theory can be perturbatively quantized and renormalized in such a way as to generate fermion and gauge boson masses. This development exploits certain freedoms inherent in choosing the unperturbed Lagrangian and in the renormalization procedure. Apart from its intrinsic interest, such a mechanism might be employed in electroweak gauge theory to generate fermion and gauge boson masses without a Higgs sector. 38 refs.
Date: February 1, 1997
Creator: Nicholson, A.F. & Kennedy, D.C.
Partner: UNT Libraries Government Documents Department

Theoretical Studies in Heterogenous Catalysis: Towards a Rational Design of Novel Catalysts for Hydrodesulfurization and Hydrogen Production

Description: Traditionally, knowledge in heterogeneous catalysis has come through empirical research. Nowadays, there is a clear interest to change this since millions of dollars in products are generated every year in the chemical and petrochemical industries through catalytic processes. To obtain a fundamental knowledge of the factors that determine the activity of heterogeneous catalysts is a challenge for modern science since many of these systems are very complex in nature. In principle, when a molecule adsorbs on the surface of a heterogeneous catalyst, it can interact with a large number of bonding sites. It is known that the chemical properties of these bonding sites depend strongly on the chemical environment around them. Thus, there can be big variations in chemical reactivity when going from one region to another in the surface of a heterogeneous catalyst. A main objective is to understand how the structural and electronic properties of a surface affect the energetics for adsorption processes and the paths for dissociation and chemical reactions. In recent years, advances in instrumentation and experimental procedures have allowed a large series of detailed works on the surface chemistry of heterogeneous catalysts. In many cases, these experimental studies have shown interesting and unique phenomena. Theory is needed to unravel the basic interactions behind these phenomena and to provide a general framework for the interpretation of experimental results. Ideally, theoretical calculations based on density-functional theory have evolved to the point that one should be able to predict patterns in the activity of catalytic surfaces. As in the case of experimental techniques, no single theoretical approach is able to address the large diversity of phenomena occurring on a catalyst. Catalytic surfaces are usually modeled using either a finite cluster or a two-dimensionally periodic slab. Many articles have been published comparing the results of these two approaches. An ...
Date: October 1, 2008
Creator: Rodriguez,J.A. & Liu, P.
Partner: UNT Libraries Government Documents Department

A research program in neutrino physics, cosmic rays and elementary particles. Progress report for Task A

Description: Physics interests of the group are focused primarily on tests of conservation laws and studies of fundamental interactions between particles. There is also a significant interest in astrophysics and cosmic rays. Task A consists of three experimental programs; a Double-Beta Decay study (currently at the Hoover Dam), a Reactor Neutrino program (until this year at Savannah River), and the IMB Proton Decay experiment in a Cleveland salt mine. Discussion of the research in each area is given.
Date: August 1, 1991
Creator: Reines, F. & Sobel, H.W.
Partner: UNT Libraries Government Documents Department

Prospects for strong interaction physics at ISABELLE. [Seven papers]

Description: Seven papers are presented resulting from a conference intended to stimulate thinking about how ISABELLE could be used for studying strong interactions. A separate abstract was prepared for each paper for inclusion in DOE Energy Research Abstracts (ERA). (PMA)
Date: January 1, 1977
Creator: Sidhu, D P & Trueman, T L
Partner: UNT Libraries Government Documents Department

Atomic processes in matter-antimatter interactions

Description: Atomic processes dominate antiproton stopping in matter at nearly all energies of interest. They significantly influence or determine the antiproton annihilation rate at all energies around or below several MeV. This article reviews what is known about these atomic processes. For stopping above about 10 eV the processes are antiproton-electron collisions, effective at medium keV through high MeV energies, and elastic collisions with atoms and adiabatic ionization of atoms, effective from medium eV through low keB energies. For annihilation above about 10 eV is the enhancement of the antiproton annihilation rate due to the antiproton-nucleus coulomb attraction, effective around and below a few tens of MeV. At about 10 eV and below, the atomic rearrangement/annihilation process determines both the stopping and annihilation rates. Although a fair amount of theoretical and some experimental work relevant to these processes exist, there are a number of energy ranges and material types for which experimental data does not exist and for which the theoretical information is not as well grounded or as accurate as desired. Additional experimental and theoretical work is required for accurate prediction of antiproton stopping and annihilation for energies and material relevant to antiproton experimentation and application.
Date: January 25, 1988
Creator: Morgan, D.L.
Partner: UNT Libraries Government Documents Department

Angle-averaged Compton cross sections

Description: The scattering of a photon by an individual free electron is characterized by six quantities: ..cap alpha.. = initial photon energy in units of m/sub 0/c/sup 2/; ..cap alpha../sub s/ = scattered photon energy in units of m/sub 0/c/sup 2/; ..beta.. = initial electron velocity in units of c; phi = angle between photon direction and electron direction in the laboratory frame (LF); theta = polar angle change due to Compton scattering, measured in the electron rest frame (ERF); and tau = azimuthal angle change in the ERF. We present an analytic expression for the average of the Compton cross section over phi, theta, and tau. The lowest order approximation to this equation is reasonably accurate for photons and electrons with energies of many keV.
Date: January 1, 1983
Creator: Nickel, G.H.
Partner: UNT Libraries Government Documents Department

Tidal disruption of a star by a supermassive black hole

Description: The analysis of stars in galactic nuclei that are captured and tidally disrupted by a black hole of mass > 10{sup 6} M{sub {circle dot}} requires the inclusion of general relativistic effects. We present the first numerical study of tidal breakup of a 1M{sub {circle dot}} main sequence star by a 10{sup 7} M{sub {circle dot}} black hole. We use a smoothed particle code to solve the hydrodynamic equations for a relativistic fluid in a static curved spacetime geometry to analyze, among other things, the fraction of the debris captured by the hole and the velocity of fragments escaping the hole.
Date: January 1, 1991
Creator: Laguna, P.; Miller, W.A. & Zurek, W.H.
Partner: UNT Libraries Government Documents Department

Shower counter resolution scaling

Description: The EM shower counter for the SDC detector has a resolution expression containing two stochastic terms plus a constant term. Recent measurements clarifying the sources of these terms are presented here. 3 refs., 4 figs.
Date: October 14, 1991
Creator: Kirk, T.B.W.
Partner: UNT Libraries Government Documents Department

Review of experiments

Description: A study was made to examine the effects which raising the ISA from 200 x 200 GeV to 400 x 400 GeV would have on the ''canonical'' experiments. These were ''canonical'' in the sense that they span the full range of foreseeable physics and have served as topics in previous Summer Studies and Workshops which resulted in quite explicit hardware designs and experimental goals. The study results indicate that all of the ''canonical'' experiments survive. Some are actually improved, some are unaffected, and some require changes which are suggested. In general, the 90/sup 0/ experiments are relatively unaffected. The single arm small angle spectrometer, the wide aperture (FATS-WASP) spectrometer and the Coulomb interference experiment have the largest number of modifications suggested. No uniqueness to these solutions are claimed, and there may be more desirable radical approaches. It is, however, felt that the 400 x 400 GeV ISA not only permits the work on conceptual experiments from previous Summer Studies to be taken over entirely, but indicates areas of improvement in many of them. Specifics of the individual experiments are discussed.
Date: August 18, 1977
Creator: Chang, C.; Yodh, G.; Cutts, D.; Lanou, R.; Engels, E.; Kramer, M. et al.
Partner: UNT Libraries Government Documents Department

Experimental studies of elementary particle interactions at high energies. Technical progress report

Description: High energy physics research at Rockefeller University is discussed. Results of e/sup +/e/sup -/ pairs experiments at the CERN ISR are summarized along with particles associated with high p/sub T/ ..pi../sup 0/ triggers and direct single ..gamma.. rays. (GHT)
Date: January 1, 1980
Creator: Cool, R.L.
Partner: UNT Libraries Government Documents Department

Compton scattering

Description: The current status of Compton scattering, both experimental observations and the theoretical predictions, is examined. Classes of experiments are distinguished and the results obtained are summarized. The validity of the incoherent scattering function approximation and the impulse approximation is discussed. These simple theoretical approaches are compared with predictions of the nonrelativistic dipole formula of Gavrila and with the relativistic results of Whittingham. It is noted that the A/sup -2/ based approximations fail to predict resonances and an infrared divergence, both of which have been observed. It appears that at present the various available theoretical approaches differ significantly in their predictions and that further and more systematic work is required.
Date: May 1, 1979
Creator: Botto, D.J. & Pratt, R.H.
Partner: UNT Libraries Government Documents Department

Slow positron study of positronium formation and diffusion in crystalline and amorphous ice

Description: The aim of the present work has been to study the interaction of low energy positrons and of Ps with a molecular solid. As a first example we have chosen ice which has been extensively investigated both by conventional positron annihilation methods as well as by many other techniques. Unlike in metals, positrons injected into most molecular solids may have a certain probability to form Ps in the bulk of the material. The process by which Ps is formed in condensed molecular materials has been a matter of strong debate. According to the Ore model of Ps formation, which is recognized as being valid for low density gases, the positron during its slowing down picks off an electron from a molecule with which it simultaneously forms Ps. For energies below E/sub L/ = I-6.8 eV, where I is the lowest ionisation energy and 6.8 eV is the Ps binding energy in vacuum, this process is not energetically possible. Above an energy E/sub u/ approx. I the model predicts a reduction of the yield of stable Ps, because of rapid slowing down of the positron by ionisation or by splitting up again of a Ps atom which may have been formed. The energy range E/sub L/ less than or equal to E approximately less than E/sub u/ is the so-called Ore gap in gases. In the present work both crystalline and amorphous ice have been studied using positrons of energies in the range 0 to 4.5 keV. The experimental methods used were determination of the yields of 3..gamma..-annihilations as well as Doppler broadening measurements in the temperature range 45 to 150 K. The main results obtained were a determination of the Ps diffusion constant, and a demonstration that in the present experiments one contribution to the total Ps yield comes from ...
Date: October 1, 1984
Creator: Lynn, K.G.; Eldrup, M.; Vehanen, A. & Schultz, P.J.
Partner: UNT Libraries Government Documents Department

Signals from flavor changing scalar neutral currents at {mu}{sup +}{mu}{sup {minus}} colliders

Description: We illustrate the possibility of observing signals from Flavor Changing Neutral Currents, originating from the scalar sector of a Two Higgs Doublet Model. In particular, we focus on the tree level process {mu}{sup +}{mu}{sup {minus}} {yields} {bar t}c + {bar c}t, via scalar exchange in the s-channel, as a distinctive process for {mu}{sup +}{mu}{sup {minus}} colliders. 12 refs., 1 fig.
Date: January 19, 1996
Creator: Reina, L.
Partner: UNT Libraries Government Documents Department

High energy physics research. Final report, October 1, 1969--December 31, 1990

Description: The goal of this research was to understand the fundamental constituents of matter and their interactions. First, a brief history of the high energy research at Princeton University is presented. Next, the extensive research covered in this 21 year period is summarized. Finally, a list of all publications issued during this period is presented.
Date: May 1995
Partner: UNT Libraries Government Documents Department

Signals from flavor changing scalar interactions in extended models

Description: If on the one hand many predictions of the Standard Model seem to be in remarkable agreement with experiments, on the other hand the full consistency of the model needs still to be proved. In particular, given our present ignorance of the Higgs sector of the theory, extensions of the Standard Model scalar sector are worth considering. The simplest extension of adding one extra SU(2) doublet of scalar fields, i.e. the Two Higgs Doublet Model, generally introduces Flavor Changing Scalar Neutral Currents. The severe constraints imposed by the low energy physics of K and B mesons (K{sup 0} {minus} {bar K}{sup 0} and B{sup 0} {minus} {bar B}{sup 0} mixing in particular) have motivated the introduction of an unnatural discrete symmetry to avoid flavor changing scalar neutral currents. This assumption may be dropped in favor of a more natural one, which takes any flavor changing coupling to be proportional to the mass of the coupled quarks. The basic idea is that a natural hierarchy is provided by the observed fermion masses and this may be transferred to the couplings between fermions and scalar fields, even when they are not the ones directly involved in the mass generation mechanism. This report presents a Yukawa lagrangian that incorporates this assumption and describes experimental consequences, involving production of top and charm quark pairs, that would serve to test it. 9 refs., 2 figs.
Date: January 19, 1996
Creator: Reina, L.
Partner: UNT Libraries Government Documents Department

Critical review of a quantitative study of a specialty in high energy particle physics

Description: A review is made of the authors' series of quantitative, historical, and social studies of the weak interactions of elementary particles. A short intellectual history, the quantitative methodology, and a summary of the papers analyzing specific episodes in this field are presented. The social organization of the field is described, and an overall policy for resource management is discussed. 6 figures, 3 tables.
Date: January 1, 1980
Creator: White, D H & Sullivan, D
Partner: UNT Libraries Government Documents Department

Medium energy nuclear physics research

Description: This paper covers the following topics: Experiment 87-02: Threshold Electrodisintegration of the Deuteron at High Q{sup 2}; Measurement of the 5th Structure Function in Deuterium and {sup 12}C; Single-Particle Densities of sd-Shell Nuclei; Experiment 84-28: Transverse Form Factors of {sup 117}Sn; Experiment 82-11: Elastic Magnetic Electron Scattering from {sup 13}C; Experiment 89-09: Measurement of the Elastic Magnetic Form Factor of {sup 3}He at High Momentum Transfer; Experiment 89-15: Coincidence Measurement of the D(e,e{prime}p) Cross-Section at Low Excitation Energy and High Momentum Transfer; Experiment 87-09: Measurement of the Quadrupole Contribution to the N {yields} {Delta} Excitation; Experiment E-140: Measurement of the x-, Q{sup 2} and A-Dependence of R = {sigma}{sub L}/{sigma}{sub T}; PEP Beam-Gas Event Analysis: Physics with the SLAC TPC/2{gamma} Detector; Drift Chamber Tests at Brookhaven National Laboratory; Experiment PR-89-031: Multi-nucleon Knockout Using the CLAS Detector; Electronics Design for the CLAS Region 1 Drift Chamber; Color Transparencies in the Electroproduction of Nucleon Resonances; and Experiment PR-89-015: Study of Coincidence Reactions in the Dip and Delta-Resonance Regions.
Date: June 1, 1992
Creator: Peterson, G.A.; Dubach, J.F.; Hicks, R.S. & Miskimen, R.A.
Partner: UNT Libraries Government Documents Department

Electromagnetic interaction of colliding beams in storage rings

Description: When the beams cross each other in the intersecton region of a storage ring, two distinct effects occur. A particle of one beam may undergo a fundamental interaction with a particle of the other beam. The average number of such events is equal to the product of the machine luminosity and the particle-particle total cross section. It is, of course, these particle interactions which the experimental physicist studies. In contrast to what happens for these fundamental interactions, a particle of one beam passing through the interaction region will always be influenced by the electric and magnetic fields produced by the entire other beam. Clearly, this classical electromagnetic interaction between the two beams will perturb the motion of the particles circulating in the machine. It is the purpose of this paper to present the basic aspects of this beam-particle force. The effect of this electrical force is quite different in the case of continuous (unbunched) proton beams which cross each other at the angle (as in the ISR at CERN and in ISABELLE at Brookhaven), as compared to the case of electron-positron bunches which collide head on (as in the SPEAR II Ring and in PETRA and PEP).
Date: January 1, 1979
Creator: Herrera, J.C.
Partner: UNT Libraries Government Documents Department

Confinement and lattice gauge theory

Description: The motivation for formulating gauge theories on a lattice to study non-perturbative phenomena is reviewed, and recent progress supporting the compatibility of asymptotic freedom and quark confinement in the standard SU(3) Yang-Mills theory of the strong interaction is discussed.
Date: June 1, 1980
Creator: Creutz, M
Partner: UNT Libraries Government Documents Department