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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

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

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

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

EPR in B physics and elsewhere

Description: The application of Einstein-Podolsky-Rosen correlations in {Upsilon}(4s) {yields} B{anti B} decays to research in CP violation is the first and probably only use of EPR as a technique for research in new physics. Elsewhere highly sophisticated EPR projects question EPR and test its predictions to look for violations of quantum mechanics, hidden variables, Bell`s inequalities, etc.
Date: September 1, 1997
Creator: Lipkin, H.J.
Partner: UNT Libraries Government Documents Department

Pentaquark phenomenology

Description: Heavy flavor hadron scattering and bound states give experimental information otherwise unobtainable on effective (qq){sub 6} and ({anti q}q){sub 8} interactions. All constituent quark model successes in (uds) hadron spectroscopy depend only on (qq){sub 3*} and ({anti q}q){sub 1} interactions. Reliable vertex detectors open new pentaquark search directions. Any event in with a proton emitted from a secondary vertex indicates a particle decaying weakly by proton emission and the discovery of a new particle if its mass is higher than that of known charmed baryons. There is no combinatorial background and striking decay signatures like p{phi}{pi}{sup {minus}} are no longer needed.
Date: September 1, 1997
Creator: Lipkin, H.J.
Partner: UNT Libraries Government Documents Department