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Full-Text Articles in Physics
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.
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.
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.
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.
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°.
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.
Wavefunction Renormalization And Nuclear Parity Nonconservation, Jf Donoghue, Br Holstein
Wavefunction Renormalization And Nuclear Parity Nonconservation, Jf Donoghue, Br Holstein
Barry R Holstein
It is argued that a recent calculation, which envisions a major role for a parity violating wave function renormalization term, predicts effects in a variety of low energy weak processes which are in contradiction to experiment. It is also shown that the physics of such renormalization terms are already included in previous work.
Long Distance Effects And Strangeness In The Nucleon, John Donoghue, Barry Holstein, Tobias Huber, Andreas Ross
Long Distance Effects And Strangeness In The Nucleon, John Donoghue, Barry Holstein, Tobias Huber, Andreas Ross
Barry R Holstein
We discuss the calculation of the strange magnetic radius of the proton in chiral perturbation theory. In particular, we investigate the low-energy component of the loop integrals involving kaons. We separate the chiral calculation into a low-energy part and a high-energy component through use of a momentum space separation scale. This separation shows that most of the chiral calculation comes from high energies where the effective field theory treatment is not valid. The resulting low-energy prediction is in better agreement with dispersive treatments. Finally, we briefly discuss magnetic moments and show how our techniques can help resolve an old puzzle …
Measurement Of The Weak Neutral Current Via Nuclear Parity Violation, Jf Donoghue, Br Holstein
Measurement Of The Weak Neutral Current Via Nuclear Parity Violation, Jf Donoghue, Br Holstein
Barry R Holstein
Present low-energy experiments which detect parity violation in nuclei are analyzed, and a consistent set of weak couplings is extracted. Using symmetries and the quark model, it is shown that a parity-violating weak-neutral-current contribution is required by the data, and we extract values sin2θW=0.0±0.4 or ρ=1.1±0.2, consistent with other determinations. The error quoted is statistical only, and does not include a possibly sizable theoretical uncertainty. On the other hand, if we assume the world-average values for ρ and θW, we can obtain from the data (with minimal quark-model assumptions) the matrix element of an operator which is closely related to …
Analysis Of Delta-S=1 Non-Leptonic Weak Decays And The Delta-I=1-2 Rule, Jf Donoghue, Eugene Golowich, Wa Ponce, Br Holstein
Analysis Of Delta-S=1 Non-Leptonic Weak Decays And The Delta-I=1-2 Rule, Jf Donoghue, Eugene Golowich, Wa Ponce, Br Holstein
Barry R Holstein
Current-algebra and quark-model methods are used to investigate hyperon and kaon transition amplitudes for various contributions to the weak nonleptonic Hamiltonian of the Weinberg-Salam model. Substantial enhancements are found for matrix elements of certain operators which are induced by quantum-chromodynamic radiative corrections and contain right-handed currents. These operators improve the agreement with experiment in most cases, although problems remain in P-wave hyperon amplitudes. In this approach, the ΔI=1/2 rule is understandable in both kaons and baryons under plausible assumptions.
Quark-Model Calculation Of The Weak Electric Coupling In Semi-Leptonic Baryon Decay, Jf Donoghue, Br Holstein
Quark-Model Calculation Of The Weak Electric Coupling In Semi-Leptonic Baryon Decay, Jf Donoghue, Br Holstein
Barry R Holstein
The weak electric form factor g2 is calculated in the nonrelativistic quark model (NRQM) and the MIT bag model for weak ΔS=1 semileptonic transitions. The bag-model result is g2/g1=0.30 with the NRQM result roughly twice this. Other weak transition form factors are tabulated, including expected SU(3)-breaking effects.
Direct Quark-Model Calculation Of Weak Nonleptonic Matrix-Elements, Jf Donoghue, Br Holstein
Direct Quark-Model Calculation Of Weak Nonleptonic Matrix-Elements, Jf Donoghue, Br Holstein
Barry R Holstein
It is shown how wave-packet techniques developed by Donoghue and Johnson may be utilized to calculate parity-violating nonleptonic hyperon decay amplitudes directly—without the use of current algebra and PCAC (partial conservation of axial-vector current).
The Principle Of Equivalence At Finite Temperature, Jf Donoghue, Br Holstein, Rw Robinett
The Principle Of Equivalence At Finite Temperature, Jf Donoghue, Br Holstein, Rw Robinett
Barry R Holstein
We demonstrate that the equivalence principle is violated by radiative corrections to the gravitational and inertial masses at finite temperature. We argue that this result can be attributed to the Lorentz noninvariance of the finite temperature vacuum.
The Van Der Waals Interaction, Br Holstein
The Van Der Waals Interaction, Br Holstein
Barry R Holstein
The interaction between two neutral but polarizable systems at separation R, usually called the van der Waals force, is discussed from different points of view. The change in character from 1/R6 to 1/R7 due to retardation is explained.
Kaon Decays And A Determination Of The Scale Of Chiral Symmetry, Jf Donoghue, Eugene Golowich, Br Holstein
Kaon Decays And A Determination Of The Scale Of Chiral Symmetry, Jf Donoghue, Eugene Golowich, Br Holstein
Barry R Holstein
Using effective chiral Lagrangians, we consider the occurrence of quadratic terms in the ΔI=1/2 K→3π matrix element. The inclusion of higher-derivative Lagrangians leads to a significant improvement over the usual current-algebra analysis. This allows an extraction directly from experimental data of Λχ, a measure of the scale of chiral symmetry. We give an operational definition of the chiral scale, and find Λχ≈1 GeV. The issue of uncertainty in the phenomenological determination of the B parameter is clarified.
Chiral Anomaly And Gamma 3 Pi, Br Holstein
Chiral Anomaly And Gamma 3 Pi, Br Holstein
Barry R Holstein
Measurement of the γ3π process has revealed a possible conflict with what should be a solid prediction generated by the chiral anomaly. We show that inclusion of appropriate energy-momentum dependence in the matrix element reduces the discrepancy.
Quantum Gravitational Corrections To The Nonrelativistic Scattering Potential Of Two Masses, Nej Bjerrum-Bohr, Jf Donoghue, Br Holstein
Quantum Gravitational Corrections To The Nonrelativistic Scattering Potential Of Two Masses, Nej Bjerrum-Bohr, Jf Donoghue, Br Holstein
Barry R Holstein
We treat general relativity as an effective field theory, obtaining the full nonanalytic component of the scattering matrix potential to one-loop order. The lowest order vertex rules for the resulting effective field theory are presented and the one-loop diagrams which yield the leading nonrelativistic post-Newtonian and quantum corrections to the gravitational scattering amplitude to second order in G are calculated in detail. The Fourier transformed amplitudes yield a nonrelativistic potential and our result is discussed in relation to previous calculations. The definition of a potential is discussed as well, and we show that the ambiguity of the potential under coordinate …
Overview Of Hadronic Parity Violation, Br Holstein
Overview Of Hadronic Parity Violation, Br Holstein
Barry R Holstein
The subject of hadronic parity violation is nearly fifty years old, but a good deal of uncertainty remains, despite many efforts both theoretical and experimental. A brief summary of the field is presented and a plan is proposed for new experimental work which, when combined with a new theoretical tack based on effective field theory, should lead to resolution of the present difficulties.
The Delta-S=2 Matrix Element For K0-Kbar0 Mixing, Jf Donoghue, Eugene Golowich, Br Holstein
The Delta-S=2 Matrix Element For K0-Kbar0 Mixing, Jf Donoghue, Eugene Golowich, Br Holstein
Barry R Holstein
We use SU(3) and PACAC to relate the ΔS = 2 matrix element Image Full-size image (1K) to experimental information on the Image contribution to K → 2π. Our results is Image which is about 33% of the vacuum insertion value.
Components Of A Chiral Coefficient, Jf Donoghue, Br Holstein
Components Of A Chiral Coefficient, Jf Donoghue, Br Holstein
Barry R Holstein
One of the coefficients that parametrizes the chiral Lagrangian of QCD is expressible in terms of a sum rule for which the integrand is known from experiment. We confront two model calculations of this coefficient with the behavior of the data. The model related to vector dominance reproduces the sumrule behavior very well, whereas a one-loop chiral quark model calculation fails badly. The sum rule allows one to identify those ingredients which are needed to make the quark method more realistic.
Chiral Symmetry And The Large-Nc Limit In Kl4 Decays, C Riggenbach, J Gasser, Jf Donoghue, Br Holstein
Chiral Symmetry And The Large-Nc Limit In Kl4 Decays, C Riggenbach, J Gasser, Jf Donoghue, Br Holstein
Barry R Holstein
The treatment of kaon decays using chiral symmetry yields predictions for thè form factors in K→ππeν. In addition, the large-Nc limit of QCD implies that a particular combination of low-energy constants should be suppressed. We present the chiral predictions for Kl4 decays at next-to-leading order in the energy expansion. By combining the phenomenologies of Kl4 and ππ scattering, we test these predictions and provide a determination of the parameters in the chiral Lagrangian of QCD.
Long-Distance Chiral Contributions To The Kl-Ks Mass Difference, Jf Donoghue, Eugene Golowich, Br Holstein
Long-Distance Chiral Contributions To The Kl-Ks Mass Difference, Jf Donoghue, Eugene Golowich, Br Holstein
Barry R Holstein
We use chiral symmetry to calculate the very long distance contributions to the KL–KS mass difference. We determine that the dominant effect arises from the two-pion dispersive contribution, which by itself produces a large result comparable to or greater than the experimental mass difference (with the correct sign). Some contributions from intermediate distance are also estimated and could be significant. These conclusions reinforce the need, first pointed out by Wolfenstein, to include an additive parameter to account for the long distance contributions in phenomenological studies of the KL–KS mass difference. This parameter may be determined from the data if the …