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An Advanced Hadron Facility: Prospects and applicability to antiproton production

Description: An Advanced Hadron Facility is designed to address physics problems within and beyond the Standard Model. High fluxes of secondary beams are needed for the requisite precision tests and searches for very rare decay modes of mesons and baryons. Such high fluxes at useful secondary energies are readily obtained from high intensity, intermediate energy proton beams, which are also well suited to antiproton production. If the AHF primary proton beam were merely dumped into a beam stop, it would produce on the order of 10/sup 19/ to 10/sup 20/ antiprotons per operating year. Current collection techniques are not likely to be capable of absorbing more than one part in 10/sup 3/ of this production. Thus, an AHF provides both the immediate possibility of collecting quantities of antiprotons substantially beyond those available from the LEF discussed at this meeting, and for significant increases in the available antiproton supply upon the development (at an AHF) of more efficient collection methods. The prospects are presently good for the completion of an AHF in the late 1990's.
Date: January 1, 1987
Creator: Goldman, T.
Partner: UNT Libraries Government Documents Department

Chiral symmetry and confinement

Description: Two principle features underlie the appearance of (approximate) chiral symmetry in hadronic systems. The first is that the conventional Dirac bispinor description of massless quarks hides the fact that this object is a direct sum of inequivalent representations of the Lorentz group. The second essential feature is that the dynamics must be chiral invariant as well. QCD satisfies this requirement by coupling equally to left and right chiral projections of the (nominally vector) color current (V /plus minus/ A) and so, to the separated components of the Dirac bispinor. The remainder of this paper describes these features.
Date: January 1, 1989
Creator: Goldman, T.
Partner: UNT Libraries Government Documents Department

Quark structure of nuclei

Description: The motivations for a direct description of nuclei in terms of quarks and gluons are discussed. A specific model implementing such a description is outlined. The importance of spin interactions for such descriptions is emphasized. Positive results, including a non-zero binding energy for a twelve quark system, are reported. Future plans and problems for refining the calculations are indicated. 18 refs.
Date: January 1, 1985
Creator: Goldman, T.
Partner: UNT Libraries Government Documents Department

Do nucleons dissolve

Description: A model is presented which describes multiquark, nuclear-like systems in a manner consistent with QCD, and with nuclear properties. Within the model, it is found that quasi-nucleon structures describe the minimum energy state of the system. This result is due to a balance between quarks lowering their kinetic energy by spreading out through the system, and lowering their color-magnetic spin-spin interaction energy by forming nucleon-like clusters. A strong core repulsion is evident, as is a realistic dip in the central matter density of the /sup 4/He-like, 12-quark system. 4 refs., 5 figs.
Date: January 1, 1985
Creator: Goldman, T.
Partner: UNT Libraries Government Documents Department

Family problems

Description: Even Grand Unified Theories may not explain the repetitive pattern of fermions in the Standard Model. The abysmal absence of dynamical information about these families is emphasized. The evidence that family quantum numbers exist, and are not conserved, is reviewed. It is argued that rare kaon decays may be the best means to obtain more information on this important question.
Date: January 1, 1984
Creator: Goldman, T.
Partner: UNT Libraries Government Documents Department

Parity violating total cross sections

Description: A diquark-quark scattering model for the parity-violating asymmetry in nucleon-nucleon scattering is described. Criticism of the model by Simonius and Unger is refuted. The strong energy dependence of the result, and the possibility of important non-valence contributions to the nucleon polarization, both support the need for further measurements at Fermilab and at Brookhaven energies. 9 refs., 7 figs.
Date: January 1, 1988
Creator: Goldman, T. & Preston, D.
Partner: UNT Libraries Government Documents Department

Gravitational properties of antimatter

Description: Quantum gravity is at the forefront of modern particle physics, yet there are no direct tests, for antimatter, of even the principle of equivalence. We note that modern descriptions of gravity, such as fibre bundles and higher dimensional spacetimes, allow violations of the commonly stated form of the principle of equivalence, and of CPT. We review both indirect arguments and experimental tests of the expected gravitational properties of CPT-conjugate states. We conclude that a direct experimental test of the gravitational properties of antimatter, at the 1% (or better) level, would be of great value. We identify some experimental reasons which make the antiproton a prime candidate for this test, and we strongly urge that such an experiment be done at LEAR. 21 references.
Date: January 1, 1985
Creator: Goldman, T. & Nieto, M.M.
Partner: UNT Libraries Government Documents Department

Discrete symmetries: A broken look at QCD

Description: The alphabet soup of discrete symmetries is briefly surveyed with a view towards those which can be tested at LISS and two particularly interesting cases are called out. A LISS experiment may be able to distinguish CP violation that is not due to the QCD {theta} term. The elements of a model of parity violation in proton-nucleon scattering, which is consistent with lower energy LAMPF and ANL results, are reviewed in the light of new information on diquarks and the proton spin fraction carried by quarks. The prediction that the parity violating total cross section asymmetry should be large at LISS energies is confirmed. The results of such an experiment can be used both to obtain new information about the diquark substructure of the nucleon and to provide bounds on new right-chiral weak interactions.
Date: August 1, 1996
Creator: Goldman, T.
Partner: UNT Libraries Government Documents Department

Inevitable'' dibaryons

Description: Two dibaryons, one with high strangeness, the other with the quantum numbers of a spin excitation of the deuteron, are found in essentially all models of QCD. Experimental proof that they are not produced at levels well below the predicted cross sections would require major revisions of our understanding of QCD. 14 refs., 4 tabs.
Date: January 1, 1991
Creator: Goldman, T.
Partner: UNT Libraries Government Documents Department

An active particle accelerator

Description: Although a static charge is difficult to maintain on macroscopic particles, it is straightforward to construct a small object with a regularly oscillating electric dipole moment. For objects of a given size, one may then construct an accelerator by appropriately matching the frequency and separations of an external array of electrodes to this size. Physically feasible size ranges, an accelerator design, and possible applications of such systems are discussed. 8 refs., 9 figs.
Date: January 1, 1991
Creator: Goldman, T.
Partner: UNT Libraries Government Documents Department

No-lost Theorem'' for parity violating nucleon-nucleon scattering experiments

Description: A purely left-chiral model of the weak interactions is used to show that the total parity-violating asymmetry in quark-quark scattering must grow with increasing energy. In the absence of other new physics, non-observation of a large asymmetry can therefore be used to infer an upper bound on the mass scale for new right-chiral weak vector bosons. Applying this idea to actual nucleon-nucleon scattering requires more involved calculations, as the dominant contribution appears to come from a component of diquark-quark scattering related to, but not identical to, wavefunction-mixing. Earlier criticism of this model by Simonius and linger is refuted, and a new calculation is proposed as an additional check on the result. Finally, we argue that the so-called 'spin crisis' does not affect our conclusions.
Date: January 1, 1993
Creator: Goldman, T.
Partner: UNT Libraries Government Documents Department

No strings attached potential vs. interaction energy in QCD

Description: In infrared-stable fixed-point field theories, the interaction energy of a test particle is proportional to the non-relativistic (heavy source) coordinate-space potential derived from the field strength produced by that source. This is no longer true in ultraviolet-stable fixed-point field theories (UVSFPFT) as they may not have a finite infrared fixed point. This leads to the possibility that UVSFPFTs may have quite conventional field strength distributions despite the unusual spatial dependence expected for the interaction energy.
Date: October 20, 1996
Creator: Goldman, T.
Partner: UNT Libraries Government Documents Department

PSEUDOSPIN SYMMETRY IN NUCLEI, SPIN SYMMETRY IN HADRONS

Description: Ginocchio argued that chiral symmetry breaking in QCD is responsible for the relativistic pseudospin symmetry in the Dirac equation, explaining the observed approximate pseudospin symmetry in sizable nuclei. On a much smaller scale, it is known that spin-orbit splittings in hadrons are small. Specifically, new experimental data from CLEO indicate small splittings in D-mesons. For heavy-light mesons we identify a cousin of pseudospin symmetry that suppresses these splittings in the Dirac equation, known as spin symmetry. We suggest an experimental test of the implications of spin symmetry for wave functions in electron-positron annihilation. We investigate how QCD can give rise to two different dynamical symmetries on nuclear and hadronic scales.
Date: August 1, 2000
Creator: PAGE, P.; GOLDMAN, T. & GINOCCHIO, J.
Partner: UNT Libraries Government Documents Department

LESSONS FROM HADRON PHENOMENOLOGY

Description: Meson spectra can be well approximated by a specific form of a nonlinear Regge trajectory which is consistent with a finite number of bound states. This may have important consequences for experiment, and may be a hint for the theory.
Date: August 1, 2000
Creator: BRISUDOVA, M.; BUAKOVSKY, L. & GOLDMAN, T.
Partner: UNT Libraries Government Documents Department

Theoretical research relevant to medium energy upgrades and experiments

Description: This is the final report of a three-year, Laboratory-Directed Research and Development (LDRD) project at the Los Alamos National Laboratory (LANL). This work provides theoretical research results for sources of pions, neutrons, neutrinos and heavy ions. The authors have undertaken specific calculations in neutrino-nucleus scattering and to analyze constraints on exotic decays relevant to the study of neutrino oscillations. They have also performed calculations regarding neutrino cosmology and astrophysics relevant to the experimental study of neutrino masses. They analyzed the constraints of data on T-violation in neutron decay and the nucleon-nucleon (NN) interaction which will be important for the understanding of experiments with cold and ultra-cold neutrons. They completed several specific calculations which were essential to predict (pion, kaon) hypernuclear production and pion-induced reactions studying baryonic resonances. They also calculated the nuclear spectroscopy of nuclei far from stability that can be studied experimentally.
Date: July 1, 1996
Creator: Goldman, T.; Benesh, C. & Carlson, J.
Partner: UNT Libraries Government Documents Department

Inevitable'' dibaryons

Description: However, the widest variation in effects arises from the color magnetic spin-spin (CMSS). In fact, since it tends to oppose quark delocalization by introducing new repulsive interactions (for example, between color-6 pairs of quarks), most dibaryon predictions are highly sensitive to the CMSS. What I want to discuss here are a few that are not sensitive, and, indeed, where the CMSS and quark delocalization act in concert to enhance binding.
Date: January 1, 1991
Creator: Goldman, T.
Partner: UNT Libraries Government Documents Department

Quantum gravity and new forces

Description: The quantum-gravity-inspired phenomenology for gravitational forces is described. New gravitational phenomena, qualitatively similar to those attributed to the so-called )openreverse arrowquotes)fifth-force)closereverse arrowquotes) are to be expected. The parameters of a model with these features have been constrained by the geophysical tests of the inverse-square law of Stacey, et al. This model is then able to explain the apparent discrepancies between the recent resuilts of Thieberger and of Adelberger and collaborators. A striking new prediction of the model is that antiprotons should experience a substantially larger gravitational acceleration than normal matter. Gravitational red-shift experiments are also proposed as tests for the new forces. 12 refs.
Date: January 1, 1988
Creator: Hughes, R.J.; Goldman, T. & Nieto, M.M.
Partner: UNT Libraries Government Documents Department

Non-Newtonian gravitational forces and the Greenland ice-sheet experiment

Description: The results of an experiment to test Newton's Inverse-Square Law of Gravitation in the Greenland ice-cap were announced recently. The anomalous gravity gradient which was found can be explained either by an unrecognized anomaly in the density of the rocks under the ice sheet, or by the existence of a non-Newtonian component of the gravitational force. Here we focus on the latter possibility, and find that the force would be attractive, with a strength between about 2.4% and 3.5% that of Newtonian gravity, and a range between about 225 m and 5.4 km. 11 refs.
Date: January 1, 1989
Creator: Hughes, R.J.; Goldman, T. & Nieto, M.M.
Partner: UNT Libraries Government Documents Department

Nuclear-like states of quark matter

Description: In a world with only one flavor of light quark, QCD suggests that the low energy states of quark matter are similar to nuclei, but are not well represented as collections of baryons. Except for the existence of open nucleon channels, the same would be true for the actual, two-light-flavor world. 3 refs.
Date: January 1, 1986
Creator: Goldman, T.; Schmidt, K.E. & Stephenson, G.J. Jr.
Partner: UNT Libraries Government Documents Department

Red-shift experiments and non-Newtonian gravitational forces

Description: The contribution of scalar non-Newtonian gravitational forces to the gravitational red-shifts is derived. The constraints imposed on scalar couplings by red-shift experiments are shown to be not competitive with those imposed by geophysical inverse-square-law experiments. 7 refs.
Date: January 1, 1989
Creator: Hughes, R.J.; Goldman, T. & Nieto, M.M.
Partner: UNT Libraries Government Documents Department