Further constraints on electron acceleration in solar noise storms

We reexamine the energetics of nonthermal electron acceleration in solar noise storms. A new result is obtained for the minimum nonthermal electron number density required to produce a Langmuir wave population of sufficient intensity to power the noise storm emission. We combine this constraint with the stochastic electron acceleration formalism developed by Subramanian & Becker (2005) to derive a rigorous estimate for the efficiency of the overall noise storm emission process, beginning with nonthermal electron acceleration and culminating in the observed radiation. We also calculate separate efficiencies for the electron acceleration -- Langmuir wave generation stage and the Langmuir wave -- noise storm production stage. In addition, we obtain a new theoretical estimate for the energy density of the Langmuir waves in noise storm continuum sources.Comment: Accepted for publication in Solar Physic

Systematic uncertainties in the precise determination of the strangeness magnetic moment of the nucleon

Systematic uncertainties in the recent precise determination of the strangeness magnetic moment of the nucleon are identified and quantified. In summary, G_M^s = -0.046 \pm 0.019 \mu_N.Comment: Invited presentation at PAVI '04, International Workshop on Parity Violation and Hadronic Structure, Laboratoire de Physique Subatomique et de Cosmologie, Grenoble, France, June 8-11, 2004. 7 pages, 16 figure

A Five-Factor Measure of Obsessive-Compulsive Personality Traits.

The current study provides convergent, discriminant, and incremental validity data for the Five-Factor Obsessive-Compulsive Inventory (FFOCI), a newly-developed measure of traits relevant to obsessive-compulsive personality disorder (OCPD) from the perspective of the five-factor model (FFM). Twelve scales were constructed as maladaptive variants of specific FFM facets (e.g., Perfectionism as a maladaptive variant of FFM competence). On the basis of data from 407 undergraduates (oversampled for OCPD symptoms) these 12 scales demonstrated convergent correlations with established measures of OCPD and the FFM. Further, they obtained strong discriminant validity with respect to facets from other FFM domains. Most importantly, the individual scales and total score of the FFOCI obtained incremental validity beyond existing measures of the FFM and OCPD for predicting a composite measure of obsessive-compulsive symptomatology. The findings support the validity of the FFOCI as a measure of obsessive-compulsive personality traits, as well as of maladaptive variants of the FFM

Strange nucleon form factors in the perturbative chiral quark model

We apply the perturbative chiral quark model at one loop to calculate the strange form factors of the nucleon. A detailed numerical analysis of the strange magnetic moments and radii of the nucleon, and also the momentum dependence of the form factors is presented.Comment: 18 pages, 6 figure

Simple quark model with chiral phenomenology

We propose a new approach to the determination of hadronic observables in which the essential features of chiral symmetry are combined with conventional constituent quark models. To illustrate the approach, we consider the simple quark model in the limit of SU~3! flavor symmetry at the strange quark mass. The comparison with data is made after an analytic continuation which ensures the correct leading nonanalytic behavior of chiral perturbation theory. The approach not only gives an excellent fit for the octet baryon magnetic moments but the prediction for the D11 magnetic moment is also in good agreement with current measurements.I. C. Cloet, D. B. Leinweber, and A. W. Thoma

Pre- and post-selected ensembles and time-symmetry in quantum mechanics

An expression is proposed for the quantum mechanical state of a pre- and post-selected ensemble, which is an ensemble determined by the final as well as the initial state of the quantum systems involved. It is shown that the probabilities calculated from the proposed state agree with previous expressions, for cases where they both apply. The same probabilities are found when they are calculated in the forward- or reverse-time directions. This work was prompted by several problems raised by Shimony recently in relation to the state, and time symmetry, of pre- and post-selected ensembles.Comment: RevTex4, 17 pages, no fig

Drum vortons in high density QCD

Recently it was shown that high density QCD supports of number of topological defects. In particular, there are U(1)_Y strings that arise due to K^0 condensation that occurs when the strange quark mass is relatively large. The unique feature of these strings is that they possess a nonzero K^+ condensate that is trapped on the core. In the following we will show that these strings (with nontrivial core structure) can form closed loops with conserved charge and currents trapped on the string worldsheet. The presence of conserved charges allows these topological defects, called vortons, to carry angular momentum, which makes them classically stable objects. We also give arguments demonstrating that vortons carry angular momentum very efficiently (in terms of energy per unit angular momentum) such that they might be the important degrees of freedom in the cores of neutron stars.Comment: 11 pages, accepted for publication in Physical Review

Liquid-gas phase transition and Coulomb instability of asymmetric nuclear systems

We use a chiral SU(3) quark mean field model to study the properties of nuclear systems at finite temperature. The liquid-gas phase transition of symmetric and asymmetric nuclear matter is discussed. For two formulations of the model the critical temperature, $T_c$, for symmetric nuclear matter is found to be 15.8 MeV and 17.9 MeV. These values are consistent with those derived from recent experiments. The limiting temperatures for finite nuclei are in good agreement with the experimental points.Comment: 14 pages, 6 figure