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MONOPONUCLEOSIS: the wonderful things that monopoles can do to nuclei if they are there

Description: In this talk we consider the wonderful things that monopoles can do to nuclei by examining nuclear physics in strong magnetic fields. We have seen that monopoles can bind nuclei. We shall investigate the following other possible processes: (1) mixing of singlet and triplet states of deuteron-like positornium; (2) production of a new kind of nuclear matter with nucleon moments oriented in the field; (3) catalysis of nuclear fission; (4) catalysis of nuclear fusion (with implications for solar neutrinos); and (5) enhancement of forbidden decays like triplet positronium, e.g., fission products.
Date: December 1, 1983
Creator: Lipkin, H.J.
Partner: UNT Libraries Government Documents Department

Multiquark exotics

Description: The question Are Anomalons Multiquark Exotics is discussed. It is concluded that so far there is no convincing experimental evidence for any multiquark exotic bound state nor for any exotic resonance. Except for the delta and S* there are no candidates for bound states and no firm theoretical predictions waiting to be tested. Exotic resonances may exist in the 1.5 to 2.0 GeV region and in the charmed sector, e.g., the charmed-strange exotics. The experimental search for multiquark resonances is still open and active. (WHK)
Date: January 1, 1983
Creator: Lipkin, H.J.
Partner: UNT Libraries Government Documents Department

Delta, iota and other meson spectroscopies

Description: This talk is given from the point of view of an experimentalist. Meson spectroscopy in the 1 to 3 GeV region is interesting because experiments exploring this region, in particular radiative psi decay, have found a rich structure of resonances too complicated to unravel with any one experiment, and not easily interpreted with any one theoretical model. None of the theoretical calculations predicting all kinds of interesting and exotic objects in this region is very convincing or reliable. Additional input from anti pp annihilation can be very useful in helping to find the answers to the following open questions: what exactly is this spectrum, what are the masses and quantum numbers of the resonances, as determined from analysis of data without theoretical prejudices; how is this spectrum described by QCD, is there evidence for new kinds of states like glue-balls, hybrids, axions, Higgses or multiquark exotics, and is there any evidence for new physics beyond QCD. 20 refs.
Date: May 1, 1986
Creator: Lipkin, H.J.
Partner: UNT Libraries Government Documents Department

Quarks and the spin of the proton for pedestrians

Description: The analysis of the EMC result on the quark contribution to the spin of the proton has caused considerable confusion and is unnecessarily complicated because of the use of SU(3) flavor symmetry to provide input on the proton wave function from hyperon decays. The basic physics can be seen by noting a clear inconsistency between the known result of the axial vector contribution to nucleon beta decay and the conventional quark-parton interpretation of the EMC result. 4 refs.
Date: January 1, 1988
Creator: Lipkin, H.J.
Partner: UNT Libraries Government Documents Department

Quarks, QCD (quantum chromodynamics) and the real world of experimental data

Description: The experimental evidence that supports quantum chromodynamics as the theory that describes how the quarks interact is briefly discussed. The indications of the existence of quarks are reviewed, and calculation of hadron masses is discussed. Additional evidence of hadron substructure as seen in the antiproton is reviewed. Arguments for the existence of color as the ''charge'' carried by quarks by which they interact are given. Hadron masses and the hyperfine interaction are presented, followed by more exotic quark systems and a study of multiquark systems. Weak interactions in the quark model are discussed. (LEW)
Date: July 1, 1987
Creator: Lipkin, H.J.
Partner: UNT Libraries Government Documents Department

Symmetry, topology and helicity in D/sub s/ /yields/ /omega//pi/ and D/sub s/ /yields/ /rho//pi/ decays

Description: Diagrams contributing to D/sub s/ /yields/ /omega//pi/ and D/sub s/ /yields/ /rho//pi/ decays are classified by topology as OZI-forbidden or disconnected, OZI-allowed or connected; by helicity as helicity-conserving, with helicity flips on both outgoing quark lines. The D/sub s/ /yields/ /omega//pi/ decay has an exotic final state and is forbidden for all annihilation diagrams which go via an intermediate state containing a single quark-antiquark pair and less than two additional gluons. It is also forbidden for helicity-conserving OZI-allowed diagrams, which are expected to be dominant and are allowed for D/sub s/ /yields/ /rho//pi/ decays. 3 refs.
Date: August 1, 1989
Creator: Lipkin, H.J.
Partner: UNT Libraries Government Documents Department

Monoponucleosis: the wonderful things that monopoles can do to nuclei if they are there

Description: In this talk we consider the wonderful things that monopoles can do to nuclei by examining nuclear physics in strong magnetic fields. We have seen that monopoles can bind nuclei. We shall investigate the following other possible processes: (1) mixing of singlet and triplet states of deuteron-like positronium; (2) production of a new kind of nuclear matter with nucleon moments oriented in the field; (3) catalysis of nuclear fission; (4) catalysis of nuclear fusion (with implications for solar neutrinos); and (5) enhancement of forbidden decays like triplet positronium, e.g. fission products.
Date: January 1, 1983
Creator: Lipkin, H.J.
Partner: UNT Libraries Government Documents Department

Quasinuclear colored quark model for hadrons. [Lectures]

Description: Lectures are presented in which a quasinuclear constituent quark model in which constituent quarks are assumed to be made of constituent interacting with a two-body color-exchange logarithmic potential is considered. The color degree of freedom is discussed in detail. Some properties of the logarithmic potential and the definition of the quasinuclear model and its validity, and a comparison of some of its predictions with experiment are described. 31 references. (JFP)
Date: September 1, 1978
Creator: Lipkin, H.J.
Partner: UNT Libraries Government Documents Department

Magnetic monopoles and dipoles in quantum mechanics

Description: The force on and the energy of a ''di-monopole'', which is the limiting case of a dipole made from two monopoles at zero separation and finite magnetic moment, interacting with an externally fixed magnetic field resulting from an electric current, is considered. A model involving only a monopole is used to illustrate the physical principles involved when magnetic sources move in a solenoidal field whose source is an electric current. The problems encountered in Hamiltonian theory are discussed. 5 refs., 3 figs. (LEW)
Date: January 1, 1986
Creator: Lipkin, H.J. & Peshkin, M.
Partner: UNT Libraries Government Documents Department

Spins of cyons and dyons

Description: We examine the meaning of the angular momentum of cyons in some detail and compare the cyon case with the more familiar case of the dyon composed of a spinless electron bound by a scalar force to a spinless magnetic monopole. This treatment differs from others not primarily in its results, but in its central point that those results follow from very simple and general properties of the angular momentum in the electromagnetic field. 6 refs., 4 figs.
Date: January 1, 1985
Creator: Lipkin, H.J. & Peshkin, M.
Partner: UNT Libraries Government Documents Department

Stodolsky's theorem and neutrino oscillation phases-for pedestrians.

Description: Neutrino oscillations are experimentally observable only as a result of interference between neutrino states with different masses and the same energy. All interference effects between neutrino states having different energies are destroyed by the interaction between the incident neutrino and the neutrino detector. Erroneous results are frequently obtained by neglecting the neutrino-detector interactions.
Date: February 19, 2003
Creator: Lipkin, H. J.
Partner: UNT Libraries Government Documents Department

Theoretical summary of the 8th International Conference on Hadron Spectroscopy

Description: The Constituent Quark Model has provided a remarkable description of the experimentally observed hadron spectrum but still has no firm theoretical basis. Attempts to provide a QCD justification discussed at Hadron99 include QCD Sum Rules, instantons, relativistic potential models and the lattice. Phenomenological analyses to clarify outstanding problems like the nature of the scalar and pseudoscalar mesons and the low branching ratio for {psi} {prime} {r_arrow} {rho} {r_arrow} {pi} were presented. New experimental puzzles include the observation of {anti p}p {r_arrow} {phi}{pi}.
Date: November 15, 1999
Creator: Lipkin, H. J.
Partner: UNT Libraries Government Documents Department

Beauty for pedestrians toy models for CP violation and baryon asymmetry

Description: Why are particles different from antiparticles? C and P Violation - 1956; CP Violation - 1964. Why so little new experimental information in thirty years? Where has all the antimatter gone? Toy models are presented showing: (1) How CPT and {Delta}I = 1/2 make life difficult in kaon physics by requiring equal K{sup {plus_minus}} total widths and also equal partial widths to many exclusive channels. (2) How to understand and get around CPT restrictions. (3) How CP asymmetries can occur in exclusive partial widths and still add up to equal total widths. (4) Sakharov`s 1966 scenario for how CP Violation + proton decay can explain baryon asymmetry (5) How B physics can help.
Date: December 1, 1995
Creator: Lipkin, H.J.
Partner: UNT Libraries Government Documents Department

Search for new physics in D{+-} {r_arrow} K{sub s}X{+-} and D{+-} {r_arrow} K{sub s}K{sub s}K{+-}.

Description: Direct CP violation beyond the standard model can be produced in charged D decays to final states with a K{sub S} by small new physics contributions to the transitions D{sup +} {r_arrow} K{sup 0}X{sup +}, where X{sup +} denotes any positively charged hadronic state or transitions D{sup +} {r_arrow} K{sup 0}{bar K}{sup 0}K{sup (*)+}, denotes any positive strange state. These transitions are doubly-Cabibbo suppressed and color suppressed in the standard model and branching ratios are experimentally observed to be suppressed by two orders of magnitude relative to the allowed D{sup +} {r_arrow} {bar K}{sup 0}X{sup +} or D{sup +} {r_arrow} {bar K}{sup 0}{bar K}{sup 0}K{sup (*)+}, branching ratio. An even smaller new physics contribution might produce an observable CP asymmetry in D{sup {+-}} {r_arrow} K{sub S}X{sup {+-}} or D{sup {+-}} {r_arrow} K{sub S}K{sub S}K{sup (*){+-}} decays. Since such asymmetries are easily checked in the early stages of any charm production experiment, it seems worth while to check them before the opportunity is lost in later stages of the analysis, even if no theoretical model predicts such an asymmetry.
Date: November 9, 1998
Creator: Lipkin, H. J.
Partner: UNT Libraries Government Documents Department

Quantum mechanics of neutrino oscillations - hand waving for pedestrians.

Description: Why Hand Waving? All calculations in books describe oscillations in time. But real experiments don't measure time. Hand waving is used to convert the results of a ''gedanken time experiment'' to the result of a real experiment measuring oscillations in space. Right hand waving gives the right answer; wrong hand waving gives the wrong answer. Many papers use wrong handwaving to get wrong answers. This talk explains how to do it right and also answers the following questions: (1) A neutrino which is a mixture of two mass eigenstates is emitted with muon in the decay of a pion at rest. This is a ''missing mass experiment'' where the muon energy determines the neutrino mass. Why are the two mass states coherent? (2) A neutrino which is a mixture of two mass eigenstates is emitted at time t=0. The two mass eigenstates move with different velocities and arrive at the detector at different times. Why are the two mass states coherent? (3) A neutrino is a mixture of two overlapping wave packets with different masses moving with different velocities. Will the wave packets eventually separate? If yes, when?
Date: December 22, 1998
Creator: Lipkin, H. J.
Partner: UNT Libraries Government Documents Department

Problems at the interface between heavy flavor physics, QCD and hadron spectroscopy.

Description: The following subjects are discussed in this report: (1) Pentaquark--why it is important and how new technologies (vertex detectors) suggest drastically different approaches form the search used by Ashery et al.; (2) problems in B decays with implications for heavy quark decays to excited light quark states like the Al; (3) problems in B and D decays to final states including {eta} and {eta}{prime} indicating that standard quark mixing might not hold; (4) possible contributions of hybrid quarkonium states to B decays; (5) heavy flavor decays to {omega}{tau} which disagree with conventional expectations; and (6) possible new spin effects in {Lambda}{sub b} decay and the effect on the lifetime difference between the {Lambda}{sub b} and B mesons.
Date: December 12, 1997
Creator: Lipkin, H. J.
Partner: UNT Libraries Government Documents Department

Problems in communication between heavy flavor experiment and hadron spectroscopy.

Description: The implications of hadron spectroscopy are generally overlooked both by experimenters presenting results and theorists making predictions. Two examples are (1) possible effects of nodes in wave functions of final state mesons produced in B decay; (2) dependence of predictions for B decays into final states containing {eta} or {eta}{prime} on models and mixing angles for these states.
Date: December 12, 1997
Creator: Lipkin, H. J.
Partner: UNT Libraries Government Documents Department

Puzzles in hyperon, charm and beauty physics.

Description: Puzzles awaiting better experiments and better theory include: (1) the contradiction between good and bad SU(3) baryon wave functions in fitting Cabibbo theory for hyperon decays, strangeness suppression in the sea and the violation of the Gottfried Sum rule--no model fits all; (2) Anomalously enhanced Cabibbo-suppressed D{sup +} {yields} K*{sup +} (s{bar d}) decays; (3) anomalously enhanced and suppressed B {yields} {eta}{prime} X decays; (4) the OZI rule in weak decays; (5) Vector dominance (W {yields} {pi}, {rho}, a{sub 1}, D{sub s}, D*{sub s}) in weak decays; (6) puzzles in doubly-cabibbo-suppressed charm decays; and (7) problems in obtaining {Lambda} spin structure from polarization measurements of produced {Lambda}'s.
Date: October 21, 2002
Creator: Lipkin, H. J.
Partner: UNT Libraries Government Documents Department

New puzzles in nonleptonic B and D decays

Description: Exclusive charged B decays show an unexplained enhancement in low-lying channels which must be reversed in other channels to equalise charged and neutral lifetimes. One suggested explanation involves decay modes with excited mesons like the a{sub 1}. The anomalous behavior of decay modes of D and B mesons into final states containing the {eta} and {eta}{prime} mesons is discussed.
Date: September 1, 1997
Creator: Lipkin, H.J.
Partner: UNT Libraries Government Documents Department