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Articles 1 - 30 of 83
Full-Text Articles in Physical Sciences and Mathematics
Limits On The Presence Of Scalar And Induced-Scalar Currents In Superallowed Beta-Decay, We Ormand, Ba Brown, Br Holstein
Limits On The Presence Of Scalar And Induced-Scalar Currents In Superallowed Beta-Decay, We Ormand, Ba Brown, Br Holstein
Barry R Holstein
Limits on the scalar and induced-scalar coupling constants are established from experimental ft values of superallowed Fermi transitions. The role of the uncertainties in the ft values is discussed, leading to minimal coupling strengths that can be extracted from ft values. The implications for the Kobayashi-Maskawa mixing angles are also discussed.
Long Range Electromagnetic Effects Involving Neutral Systems And Effective Field Theory, Br Holstein
Long Range Electromagnetic Effects Involving Neutral Systems And Effective Field Theory, Br Holstein
Barry R Holstein
We analyze the electromagnetic scattering of massive particles with and without spin wherein one particle (or both) is electrically neutral. Using the techniques of effective field theory, we isolate the leading long distance effects, both classical and quantum mechanical. For spinless systems results are identical to those obtained earlier via more elaborate dispersive methods. However, we also find new results if either or both particles carry spin.
Neutrino Physics, Wc Haxton, Br Holstein
Neutrino Physics, Wc Haxton, Br Holstein
Barry R Holstein
The basic concepts of neutrino physics are presented at a level appropriate for integration into elementary courses on quantum mechanics and/or modern physics
Klein's Paradox, Br Holstein
Klein's Paradox, Br Holstein
Barry R Holstein
Klein’s paradox is shown to be resolved by a careful consideration of Feynman’s picture of antiparticles as negative energy solutions traveling backward in time. Implications associated with the spin-statistics theorem are pointed out.
Electric-Dipole Moments Of Nuclei, Jf Donoghue, Br Holstein, Mj Musolf
Electric-Dipole Moments Of Nuclei, Jf Donoghue, Br Holstein, Mj Musolf
Barry R Holstein
Recent calculations by Sushkov, Flambaum and Khriplovich have suggested that the existence of the possibility of kaon exchange within nuclei allows nuclear electric dipole moments within the standard model to be enhanced substantially over those of nucleons. This suggestion is analysed carefully and it is found that the constraints of chiral symmetry, which were not correctly included in the earlier calculation, reduce this prediction substantially.
The Lifetime Of A Deeply Bound H Dibaryon And The Cygnus-X-3 Events, Jf Donoghue, Eugene Golowich, Br Holstein
The Lifetime Of A Deeply Bound H Dibaryon And The Cygnus-X-3 Events, Jf Donoghue, Eugene Golowich, Br Holstein
Barry R Holstein
The explanation of the Cygnus X-3 events which involves a strange-quark star emitting the doubly strange H dibaryon requires the H to have a lifetime of greater than ten years. We calculate the ΔS=2 H→ NN for an H bound below ΛN threshold, and find τHless, approximate6 days.
Fundamental Neutron Physics: Introduction And Overview Preface, Br Holstein
Fundamental Neutron Physics: Introduction And Overview Preface, Br Holstein
Barry R Holstein
In the 77 years since its discovery by Chadwick in 1932, the neutron has come to play an increasingly important role in contemporary physics. As the next to lightest baryon, it is, of course, one of the two primary components of the atomic nucleus and studies of isotopes (nuclei with varying numbers of neutrons but the same proton number) and of the neutron drip line are one of the important focuses of the recently approved radioactive beam machine to be built at Michigan State University. Precise knowledge of its ~900 second lifetime is crucial to determination of the time at …
Limit On 2nd Class Polar Vector Couplings In Semileptonic Weak-Interactions, Br Holstein
Limit On 2nd Class Polar Vector Couplings In Semileptonic Weak-Interactions, Br Holstein
Barry R Holstein
Although a great deal of experimental work has succeeded in limiting a possible second class axial coupling to about ten percent of the size of weak magnetism, published limits on the size of a possible second class polar vector current are one order of magnitude less sensitive. We summarize the present situation and demonstrate that muon capture provides the strictest present limit.
Symmetry-Tests And Standard Model Backgrounds, Br Holstein
Symmetry-Tests And Standard Model Backgrounds, Br Holstein
Barry R Holstein
No abstract provided.
Hot Curved Space And The Jeans Mass, Br Holstein
Hot Curved Space And The Jeans Mass, Br Holstein
Barry R Holstein
We construct the effective Lagrangian for a noninteracting scalar field at nonzero temperature in curved spacetime. Metric fluctuations are evaluated, resulting in an energy momentum tensor which has the form expected for an imperfect fluid. Such fluctuations are found to be unstable (for most values of the cosmological constant) with an exponential growth characterized by a Jeans mass squared which is twice the classical value.
The Reaction Gamma-Gamma-]Pi-0-Pi-0 And Chiral Loops, Jf Donoghue, Br Holstein, Yc Lin
The Reaction Gamma-Gamma-]Pi-0-Pi-0 And Chiral Loops, Jf Donoghue, Br Holstein, Yc Lin
Barry R Holstein
Two-photon production of a neutral-pion pair is uniquely predicted near threshold by the theory of chiral symmetry. The prediction vanishes at the tree level and is nonzero only at one-loop order, yielding a finite result without any unknown counterterms. In this paper we calculate the cross section for both on-shell and off-shell photons, as both cases can both be studied at e+e- storage rings. This reaction is the most accessible process which directly probes the loop structure of chiral-SU(2) symmetry.
Low-Energy Weak-Interactions Of Quarks, Jf Donoghue, Eugene Golowich, Br Holstein
Low-Energy Weak-Interactions Of Quarks, Jf Donoghue, Eugene Golowich, Br Holstein
Barry R Holstein
We review the progress that has been made in understanding weak interaction effects in hadrons. Our focus is on the quark model and its role in connecting hadronic processes with the underlying SU(2)L × U(1) weak interaction theory. Open questions, new techniques and future directions are also discussed.
Quantum-Mechanics In Curved Space, Jf Donoghue, Br Holstein
Quantum-Mechanics In Curved Space, Jf Donoghue, Br Holstein
Barry R Holstein
The quantum mechanical wave equation for a particle in a Schwarzschild metric is derived using general relativity in the linearized approximation. The significance of the various terms in the effective Hamiltonian is discussed and shown to be associated with the post‐Newtonian terms for the corresponding classical motion.
Mass Ratios Of The Light Quarks, Jf Donoghue, Br Holstein, D Wyler
Mass Ratios Of The Light Quarks, Jf Donoghue, Br Holstein, D Wyler
Barry R Holstein
We derive a consistent set of light quark mass ratios which are compatible with the available constraints of chiral symmetry treated to next-to-leading order. Also required as input is resonance saturation of a set of low-energy amplitudes, in particular for the pion and kaon electromagnetic mass difference. The results (md+mu)/ms=1/15.5, (md-mu)/ms=1/29 are modestly different from previous values, and resolve the long-standing puzzle of the η→3π decay rate.
Hadronic Parity Violation, Br Holstein
Hadronic Parity Violation, Br Holstein
Barry R Holstein
We review the state of hadronic parity violation and propose a program based on a new effective field theory potential which can resolve the present confusion.
Anions And Anomalies, M Bawin, Sa Coon, Br Holstein
Anions And Anomalies, M Bawin, Sa Coon, Br Holstein
Barry R Holstein
We analyze the recent claim that experimental measurements of binding energies of dipole-bound anions can be understood in terms of a quantum mechanical anomaly. The discrepancy between the experimental critical dipole moments and that predicted by the anisotropic inverse square potential of a static dipole precludes such an explanation. As has long been known, in the physical problem one must include rotational structure so that the long distance behavior changes from 1/r2 to 1/r4. In a simple model this can be shown to lead to a modification of the critical dipole moment of 20% or so, bringing it into agreement …
Strong Bounds On Weak Couplings, Jf Donoghue, Br Holstein
Strong Bounds On Weak Couplings, Jf Donoghue, Br Holstein
Barry R Holstein
Analysis of nonleptonic ΔS = 1 weak decays strongly restricts the possible size of right-handed weak couplings. Limits thus obtained are competitive with those obtained via other means.
Effective Effective Interactions, Br Holstein
Effective Effective Interactions, Br Holstein
Barry R Holstein
The use of effective field theory techniques allows the basic physics to be extracted from otherwise complex systems. We cite examples from quantum mechanics, condensed-matter physics, QCD, and quantum gravity.
Electromagnetic Simulation Of T Noninvariance In Nuclear Beta-Decay, Br Holstein
Electromagnetic Simulation Of T Noninvariance In Nuclear Beta-Decay, Br Holstein
Barry R Holstein
We calculate the simulation of T-violating correlations induced by final state electromagnetic interactions in nuclear beta decay. RADIOACTIVITY Nuclear beta decay, calculated final state Coulomb simulation of T violation.
How Large Is F-Pi, Br Holstein
How Large Is F-Pi, Br Holstein
Barry R Holstein
We note that the 93.1 MeV value of the pion decay constant used by most investigators is nearly a per cent too large due to the incomplete inclusion of radiative corrections in its extraction. The new value 92.4 MeV, when combined with the value of the nucleon axial coupling gA, gives improved agreement with the Gorger-Treiman relation.
Evidence For Su(3) Breaking In Cabibbo-Type Fits Of Semi-Leptonic Hyperon Decay, Jf Donoghue, Br Holstein
Evidence For Su(3) Breaking In Cabibbo-Type Fits Of Semi-Leptonic Hyperon Decay, Jf Donoghue, Br Holstein
Barry R Holstein
We analyze recent precision experiments involving semileptonic hyperon decay and demonstrate that there exists definite evidence for SU(3) breaking. The type of breaking observed is a difference in the D/(F+D) ratios in the ΔS=0 and ΔS=1 sectors, which is at variance with the simplest quark-model expectations. We comment on the relevance of symmetry breaking to the determination of weak mixing angles.
Electromagnetic Self-Energies Of Pseudoscalar Mesons And Dashen Theorem, Jf Donoghue, Br Holstein, D Wyler
Electromagnetic Self-Energies Of Pseudoscalar Mesons And Dashen Theorem, Jf Donoghue, Br Holstein, D Wyler
Barry R Holstein
The calculation of the electromagnetic mass shifts of π, K mesons is studied using a model incorporating chiral symmetry and vector dominance. Significant SU(3) breaking to Dashen's theorem is found, allowing a resolution of the long-standing discrepancy between the quark-mass ratio (md-mu)/ms found from η→3π decay and that from the K+-K0 mass difference.
Chiral Loops In Pi-0,Eta-0-]Gamma-Gamma And Eta-Eta' Mixing, Jf Donoghue, Br Holstein, Ycr Lin
Chiral Loops In Pi-0,Eta-0-]Gamma-Gamma And Eta-Eta' Mixing, Jf Donoghue, Br Holstein, Ycr Lin
Barry R Holstein
We compute the one-loop corrections to the Wess-Zumino Lagrangean governing π0, η8→γγ. The SU(3) relation between the two decay rates receives modifications of order mK2lnmK2, as does the Gell-Mann-Okubo mass formula. A consistent picture of η-η′ mixing emerges from both the two-photon widths and the mass matrix, however with a mixing angle θ≈-20° instead of the usual θ≈-10°.
Dispersive Effects In D0-Dbaro Mixing, Jf Donoghue, Eugene Golowich, Br Holstein, J Trampetic
Dispersive Effects In D0-Dbaro Mixing, Jf Donoghue, Eugene Golowich, Br Holstein, J Trampetic
Barry R Holstein
We estimate the size of dispersive effects in ΔC=2 interactions and find that they represent in fact the dominant components of D0-D¯0 mixing. The box diagram is suppressed by several orders of magnitude due to the small values of light-quark masses. Crucial to this argument is a discussion of how the Glashow-Iliopoulos-Maiani mechanism works in the dispersive sector.
Subnuclear Structure - Nucleons Just Yield To Pressure, Br Holstein
Subnuclear Structure - Nucleons Just Yield To Pressure, Br Holstein
Barry R Holstein
No abstract provided.
Light Baryon Magnetic Moments And N ->Delta Gamma Transition In A Lorentz Covariant Chiral Quark Approach, A Faessler, T Gutsche, Br Holstein, Ve Lyubovitskij, D Nicmorus, K Pumsa-Ard
Light Baryon Magnetic Moments And N ->Delta Gamma Transition In A Lorentz Covariant Chiral Quark Approach, A Faessler, T Gutsche, Br Holstein, Ve Lyubovitskij, D Nicmorus, K Pumsa-Ard
Barry R Holstein
We calculate magnetic moments of light baryons and N→Δγ transition characteristics using a manifestly Lorentz covariant chiral quark approach for the study of baryons as bound states of constituent quarks dressed by a cloud of pseudoscalar mesons.
Nuclear Parity Violation 1984 - An Optimists Perspective, Br Holstein
Nuclear Parity Violation 1984 - An Optimists Perspective, Br Holstein
Barry R Holstein
The present theoretical understanding of nuclear parity nonconservation is assesssed. Using the quark model to calculate weak couplings and empirical values obtained in s-d nuclei we determine sin2thetaw=0.33±0.19. Unfortunately, the error bars here are purely statistical and do not include a substantial ``systematic'' uncertainty associated with the theory.
Hadronic Parity Violation: Past, Present, And Future, Br Holstein
Hadronic Parity Violation: Past, Present, And Future, Br Holstein
Barry R Holstein
The history of hadronic parity violation is reviewed, from its beginning in 1957 to the present time. The current state of the subject is shown to be confused and a program to resolve this dilemma, including theoretical calculations using effective theoretic methods together with new low energy experiments in low A systems, is proposed.
Temperature Measured By A Uniformly Accelerated Observer, Jf Donoghue, Br Holstein
Temperature Measured By A Uniformly Accelerated Observer, Jf Donoghue, Br Holstein
Barry R Holstein
By use of elementary quantum‐mechanical arguments we demonstrate how an observer with uniform acceleration a perceives himself as immersed in a heat bath of temperature kT=aℏ/2πc.
The Stability Of Hot Curved Space, Ps Gribosky, Jf Donoghue, Br Holstein
The Stability Of Hot Curved Space, Ps Gribosky, Jf Donoghue, Br Holstein
Barry R Holstein
The propagator is evaluated for the situation of a non-interacting scalar field at non-zero temperature in curved space-time. The coincidence limit is taken and the corresponding effective Lagrangian is constructed. Fluctuations are determined using a background metric which satisfies the Einstein equations. The resulting energy-momentum tensor is found to be that for an imperfect fluid. Metric fluctuations are found to be unstable (for most values of the cosmological constant) with an exponential growth characterized by a Jeans mass squared which is twice the classical value. Comparisons with previous calculations are also made.