Showing papers on "Pseudoscalar published in 1978"
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TL;DR: In this article, it was pointed out that a global U(1) symmetry, introduced in order to preserve the parity and time-reversal invariance of strong interactions despite the effects of instantons, would lead to a neutral pseudoscalar boson, the "axion", with mass roughly of order 100 keV to 1 MeV.
Abstract: It is pointed out that a global U(1) symmetry, that has been introduced in order to preserve the parity and time-reversal invariance of strong interactions despite the effects of instantons, would lead to a neutral pseudoscalar boson, the "axion," with mass roughly of order 100 keV to 1 MeV. Experimental implications are discussed.
4,138 citations
TL;DR: In this article, the color gauge theory of strong interactions without arbitrary adjustment of parameters is analyzed and several possibilities are identified, including one which would give a remarkable new kind of very light, long-lived pseudoscalar boson.
Abstract: The requirement that P and T be approximately conserved in the color gauge theory of strong interactions without arbitrary adjustment of parameters is analyzed. Several possibilities are identified, including one which would give a remarkable new kind of very light, long-lived pseudoscalar boson.
3,878 citations
CERN1
TL;DR: In this article, the minimal set of auxiliary fields of supergravity is defined, needed to close the supergravity algebra, and the invariant action is shown to be invariant to a scalar, a pseudoscalar and a world vector field.
360 citations
TL;DR: Lower bounds on the mass of a light scalar (Higgs) or pseudoscalar (axion) particle are found in three ways: (1) by requiring that their effect on primordial nucleosynthesis not yield a deuterium abundance outside present experimental limits, (2) that the photons from their decay thermalize and not distort the microwave background, and (3) that their emission from helium burning stars (red giants) not disrupt stellar evolution as mentioned in this paper.
Abstract: Lower bounds on the mass of a light scalar (Higgs) or pseudoscalar (axion) particle are found in three ways: (1) by requiring that their effect on primordial nucleosynthesis not yield a deuterium abundance outside present experimental limits, (2) by requiring that the photons from their decay thermalize and not distort the microwave background, and (3) by requiring that their emission from helium-burning stars (red giants) not disrupt stellar evolution. The best bound is from (3); it requires the axion or Higgs-particle mass to be greater than about 0.2 MeV.
160 citations
01 Apr 1978
TL;DR: Lower bounds on the mass of a light scalar (Higgs) or pseudoscalar (axion) particle are found in three ways: (1) by requiring that their effect on primordial nucleosynthesis not yield a deuterium abundance outside present experimental limits, (2) that the photons from their decay thermalize and not distort the microwave background, and (3) that their emission from helium burning stars (red giants) not disrupt stellar evolution as mentioned in this paper.
Abstract: Lower bounds on the mass of a light scalar (Higgs) or pseudoscalar (axion) particle are found in three ways: (1) by requiring that their effect on primordial nucleosynthesis not yield a deuterium abundance outside present experimental limits, (2) by requiring that the photons from their decay thermalize and not distort the microwave background, and (3) by requiring that their emission from helium-burning stars (red giants) not disrupt stellar evolution. The best bound is from (3); it requires the axion or Higgs-particle mass to be greater than about 0.2 MeV.
128 citations
TL;DR: In this paper, the mass of the η c meson is calculated by means of QCD sum rules, and the spectrum of the 0 − states of charmonium contains a single prominent resonance, like the J/ψ in the case of vector states, not 2.83.
85 citations
TL;DR: In this paper, the superfluid state of fermion-antifermion fields is generalized to include higher orbital and spin states, and the concept that the basic (unmanifest) FME-ANTIFMion interaction can lead to a multiplicity of manifest interactions seems to provide a basis for a unified field theory.
Abstract: The superfluid state of fermion-antifermion fields developed in our previous papers is generalized to include higher orbital and spin states. In addition to single-particle excitations, the system is capable of having real and virtual bound or quasibound composite excitations which are akin to bosons of spinJP equal to0−, 1−, 2+, etc. These pseudoscalar, vector, and tensor bosons can be massive or massless and provide the vehicles for strong, electromagnetic, weak, and gravitational interactions. The concept that the basic (unmanifest) fermion-antifermion interaction can lead to a multiplicity of manifest interactions seems to provide a basis for a unified field theory.
29 citations
TL;DR: In this article, a model for gloun jet fragmentation based on QCD was considered, where the fast hadrons in the jet are produced by the sequential reaction gluon → q q q → hadrons.
28 citations
TL;DR: In this article, an explicit formula for the beta-ray angular distribution by taking into account the radiative corrections, Coulomb corrections of the finite-size nucleus, weak magnetism, induced pseudoscalar, second-class induced tensor, and contributions of the d-wave leptons was made.
20 citations
TL;DR: In this article, the authors studied the production of K∗±(892) and KS0 in pp annihilations at 0.76 GeV/c. Longitudinal and transverse momentum distributions are presented.
19 citations
TL;DR: For arbitrary-spin fields new tensor and pseudotensor interactions arise while for spin-1/2 fields the theory reduces to Cartan's equations, apart from a reduction in the spin-spin coupling constant as mentioned in this paper.
Abstract: The Einstein-Cartan theory of gravitation is generalized by the addition of the most general action which is bilinear in the antisymmetric part of the connection and linear in the Levi-CIvita density and hence contains both scalar and pseudoscalar contributions. For arbitrary-spin fields new tensor and pseudotensor interactions arise while for spin-1/2 fields the theory reduces to Cartan's equations, apart from a reduction in the spin-spin coupling constant.
TL;DR: In this article, a universal confining interaction which increases linearly with the distance between the quarks and treating exactly the asymptotic freedom constraint on αs was proposed.
TL;DR: In this paper, the chirality functions in one or more ligand parameters representing pseudoscalar molecular properties are decompose as linear combinations in the elementary chiral functions of a suitable module basis.
Abstract: Analytic chirality functions in one or more ligand parameters representing pseudoscalar molecular properties are shown to decompose as linear combinations in the elementary chirality functions of a suitable module basis The implications of this decomposition for an approximation ansatz are considered
TL;DR: In this paper, it was shown that a previously developed formalism for representing microscopic charge and current densities in terms of polarisation and magnetisation fields can be written in a manifestly Lorentz covariant manner.
Abstract: It is shown that a previously developed formalism (Healy 1977) for representing microscopic charge and current densities in terms of polarisation and magnetisation fields can be written in a manifestly Lorentz covariant manner. The charge-current density four-vector associated with an aggregate of charged point particles is first constructed and its behaviour under the time reversal transformation is discussed. Particular polarisation-magnetisation tensors defined as sums of line integrals of delta functions are then shown to reproduce the charge and current densities in the required fashion; it is noted that the components of these tensors, although involving instantaneous integrals along spatial curves, are defined in the same way by all observers related by homogeneous Lorentz transformations, provided only that the speed of any point of the curves is less than c. The general polarisation-magnetisation tensor is derived through a transformation generated by an arbitrary pseudovector field. The explicit form of this field, as well as of a subsidiary pseudoscalar field, is obtained for those transformations that interrelate polarisation-magnetisation tensors of the line integral kind.
TL;DR: In this paper, the contributions of the radially excited pseudoscalar mesons, whose existence is predicted in the quark model, were evaluated by taking into account the contribution of the pseudoscales to the axial vector current.
Abstract: Corrections to the partially conserved axial-vector current hypothesis are evaluated by taking into account the contributions of the radially excited pseudoscalar mesons, whose existence is predicted in the quark model. The coupling of these mesons to the axial-vector current is first order in chiral-symmetry breaking. Several sum rules, related to matrix elements of light-plane commutators of charges and divergences of currents, are analyzed. Predictions are made for some decay modes of the radially excited pseudoscalar and vector mesons.
TL;DR: In this paper, the non-equivalence of pseudoscalar and pseudovector coupling of a pion to a Dirac nucleon in the presence of a scalar-vector potential is analyzed and found to be strongly related to the magnitude of spin-orbit splitting.
TL;DR: In this paper, the compositeness of mesons is taken into account in the evaluation of decays and mixing of eta, eta', and eta/sub c/ with an idea abstracted from quantum chromodynamics.
Abstract: The compositeness of mesons is taken into account in the evaluation of decays and mixing of eta, eta', and eta/sub c/ with an idea abstracted from quantum chromodynamics. Effective couplings of a pseudoscalar meson and two gluons are calculated in a simple model, where the Bethe-Salpeter amplitude is approximated in terms of harmonic-oscillator wave functions. The model is constructed so as to reproduce S-wave meson masses and the values of wave functions at the origin in the sense of the nonrelativistic quark model. In this model GAMMA (..pi../sup 0/ ..-->.. 2..gamma..) is reproduced satisfactorily. We obtain an s-dependent mixing angle, which is estimated to be - 42.3/sup 0/ and - 40.0/sup 0/ for s = M/sub eta//sup 2/ and s = M/sub etaprime//sup 2/, respectively. Criticism of various estimations of the angle is presented. All the results are shown to be consistent with experiments. The importance of the compositeness of mesons is stressed.
TL;DR: In this paper, the decays of pseudoscalar mesons containing heavy $t$ or $b$ quarks are discussed and it is shown that production by neutrinos should not lead to any substantial increase in the observed dimuon rate above threshold.
Abstract: The decays of pseudoscalar mesons containing heavy $t$ or $b$ quarks is discussed. In particular, we show that $t$ or $b$ production by neutrinos should not lead to any substantial increase in the observed dimuon rate above threshold.
TL;DR: In this paper, the exact vanishing of all β functions of the Callan-Symanzik equation was proved in a two-dimensional model with Thirring and gradient couplings, where ψ, π and σ are fermion, pseudoscalar and scalar massive fields.
01 May 1978
TL;DR: In this article, the effects of resonance production on the meson inclusive distribution in the fragmentation region were investigated in the framework of the parton recombination model, and a reliable ratio of the vector-to-pseudoscalar rates was determined, and the influence of the decay of vector mesons on the pseudoscalar spectrum was examined.
Abstract: Possible effects of resonance production on the meson inclusive distribution in the fragmentation region are investigated in the framework of the parton recombination model From a detailed study of the data on vector-meson production, a reliable ratio of the vector-to-pseudoscalar rates is determined Then the influence of the decay of the vector mesons on the pseudoscalar spectrum is examined, and the effect found to be no more than 25% for x > 05 The normalization of the non-strange antiquark distributions are still higher than those in a quiescent proton The agreement between the calculated results and data remain very good 36 references
CERN1
TL;DR: In this paper, a modification of the Faddeev-Popov quantization rules for Poincare supergravity in the second-order formalism is presented, in which a four-ghost coupling is needed.
Abstract: Unitarity requires a modification of the Faddeev-Popov quantization rules for Poincare supergravity in the second-order formalism. In particular a four-ghost coupling is needed. By introducing a scalar, a pseudoscalar and an axial vector auxiliary field, the gauge algebra closes and ordinary Faddeev-Popov quantization is applicable. Elimination of the auxiliary fields after quantization reproduces the four-ghost coupling.
TL;DR: In this paper, the authors considered two modes of spontaneous breakdown of chiralSUN×SUN: i) sUN×sUN→SUN and ii) s SUN×S SUN→S SUN−1×SIN−1−SUN−1-U1 −1−U1, and derived typical low-energy theorems.
Abstract: We consider two modes of spontaneous breakdown of chiralSUN×SUN: i)SUN×SUN→SUN and ii)SUN×SUN→SUN−1×SUN−1×U1. The models consists of aN-plet of fermion fields. The Goldstone bosons appear as scalar or pseudoscalar fermion-antifermion bound states. The dynamically rearranged symmetry is obtained for both modes of breaking; for mode ii) it is found that the generators of the asymptotic symmetry do not form a closed algebra. We also derive typical low-energy theorems, and discuss the different implications of the two modes of breaking.
TL;DR: In this article, the mass spectra of hadrons in the bag model with surface tension were compared with those of the MIT bag model, and it was found that the masses of the hadrons did not depend significantly on the type of confining pressure except for the pseudoscalar particles.
01 May 1978
TL;DR: In this article, the effects of resonance production on the meson inclusive distribution in the fragmentation region are investigated in the framework of the parton recombination model, and a reliable ratio of the vector-to-pseudoscalar rates is determined.
Abstract: Possible effects of resonance production on the meson inclusive distribution in the fragmentation region are investigated in the framework of the parton recombination model From a detailed study of the data on vector-meson production, a reliable ratio of the vector-to-pseudoscalar rates is determined The authors examine the influence of the decay of the vector mesons on the pseudoscalar spectrum and find the effect to be no more than 25% for x>05 The normalisation of the nonstrange antiquark distributions are still higher than those in a quiescent proton
TL;DR: In this paper, it was shown that a negative slope for the form factor in pseudoscalar Dalitz decays can be explained by vector-meson dominance with a subtracted dispersion relation.
Abstract: It is pointed out that a negative slope for the form factor in pseudoscalar Dalitz decays can be explained by vector-meson dominance with a subtracted dispersion relation. Calculations are made for the pi 0 and eta using the experimental omega to pi 0 gamma , phi to pi 0 gamma and phi to eta gamma decay rates and SU(3) symmetry. An incidental consequence of these calculations is that excitable colour gluons do not significantly affect eta Dalitz decay.
TL;DR: In this paper, the authors considered the inclusion of pseudoscalar mesons in a parameter-free Mueller-Regge model with absorption corrections, and the inclusive cross sections for fixed t and fixed M2/s were given.
Abstract: The inclusive production of pseudoscalar mesons is considered in a parameter-free Mueller-Regge model with absorption corrections. The inclusive cross sections for fixed t and fixed M2/s are given.
TL;DR: In this article, the decay rates for the radiative processes were calculated with a phenomenological Hamiltonian in a broken-SU4 model, using the mixing scheme of Kajantieet et al. and introducing a mass-dependent suppression factor.
Abstract: The decay rates for the radiative processes 1− → 0− γ and 0− → 1− γ are calculated with a phenomenological Hamiltonian in a broken-SU4 model proposed by Gaillardet al., using the mixing scheme of Kajantieet al. and introducing a mass-dependent suppression factor. The model predicts the existence of a vector meson ϕc and of pseudoscalar mesons ηc of masses 2.77 GeV and 2.37 GeV, respectively. The rates we found are either in the keV range or smaller.
TL;DR: In this paper, the effect of the neutral weak current on the decay mode of a neutral pseudoscalar meson (π0 or η) into a photon and a leptonantilepton pair has been calculated within the framework of the Weinberg-Salam model.
Abstract: The effect of the neutral weak current on the decay mode of a neutral pseudoscalar meson (π0 or η) into a photon and a leptonantilepton pair has been calculated within the framework of the Weinberg-Salam model. A parity-violating contribution to the decay spectrum is found to be larger for the decay η→γμ+μ−. In this case it can be of the order 10−6 strongly depending on the value of the Weinberg angle and thus is still beyond the present experimental possibilities. However, a measurement of this effect would not only give a strong hint on the value of the Weinberg angle, but could also help to resolve the difficulties of the Weinberg-Salam model in atomic-physics experiments.