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Title: Charge Density of a Positively Charged Vector Boson May Be Negative

Abstract

The charge density of vector particles, for example W{sup {+-}}, may change sign. The effect manifests itself even for a free propagation, when the energy of the W-boson satisfies {epsilon}>{radical}(2)m and the standing wave is considered. The charge density of W also changes sign in a vicinity of a Coulomb center. For an arbitrary vector boson (e.g., for spin 1 mesons), this effect depends on the g-factor. An origin of this surprising effect is traced to the electric quadrupole moment and spin-orbit interaction of vector particles; their contributions to the current have a polarization nature. The corresponding charge density equals {rho}{sub Pol}=-{nabla}{center_dot}P, where P is an effective polarization vector that depends on the quadrupole moment and spin-orbit interaction. This density oscillates in space, producing zero contribution to the total charge.

Authors:
;  [1]
  1. School of Physics, University of New South Wales, Sydney 2052 (Australia)
Publication Date:
OSTI Identifier:
20951332
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review Letters; Journal Volume: 98; Journal Issue: 18; Other Information: DOI: 10.1103/PhysRevLett.98.181805; (c) 2007 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; CHARGE DENSITY; L-S COUPLING; LANDE FACTOR; POLARIZATION; QUADRUPOLE MOMENTS; SPIN; STANDING WAVES; VECTOR MESONS; W MINUS BOSONS; W PLUS BOSONS

Citation Formats

Flambaum, V. V., and Kuchiev, M. Yu.. Charge Density of a Positively Charged Vector Boson May Be Negative. United States: N. p., 2007. Web. doi:10.1103/PHYSREVLETT.98.181805.
Flambaum, V. V., & Kuchiev, M. Yu.. Charge Density of a Positively Charged Vector Boson May Be Negative. United States. doi:10.1103/PHYSREVLETT.98.181805.
Flambaum, V. V., and Kuchiev, M. Yu.. Fri . "Charge Density of a Positively Charged Vector Boson May Be Negative". United States. doi:10.1103/PHYSREVLETT.98.181805.
@article{osti_20951332,
title = {Charge Density of a Positively Charged Vector Boson May Be Negative},
author = {Flambaum, V. V. and Kuchiev, M. Yu.},
abstractNote = {The charge density of vector particles, for example W{sup {+-}}, may change sign. The effect manifests itself even for a free propagation, when the energy of the W-boson satisfies {epsilon}>{radical}(2)m and the standing wave is considered. The charge density of W also changes sign in a vicinity of a Coulomb center. For an arbitrary vector boson (e.g., for spin 1 mesons), this effect depends on the g-factor. An origin of this surprising effect is traced to the electric quadrupole moment and spin-orbit interaction of vector particles; their contributions to the current have a polarization nature. The corresponding charge density equals {rho}{sub Pol}=-{nabla}{center_dot}P, where P is an effective polarization vector that depends on the quadrupole moment and spin-orbit interaction. This density oscillates in space, producing zero contribution to the total charge.},
doi = {10.1103/PHYSREVLETT.98.181805},
journal = {Physical Review Letters},
number = 18,
volume = 98,
place = {United States},
year = {Fri May 04 00:00:00 EDT 2007},
month = {Fri May 04 00:00:00 EDT 2007}
}
  • The charge density of vector particles, for example W{sup {+-}}, may change sign. The effect manifests itself even for a free propagation, when the energy of the W-boson satisfies {var_epsilon} > {radical}2m and the standing wave is considered. The charge density of W also changes sign in a vicinity of a Coulomb center. For an arbitrary vector boson (e.g., for spin 1 mesons), this effect depends on the g-factor. An origin of this surprising effect is traced to the electric quadrupole moment and spin-orbit interaction of vector particles; their contributions to the current have a polarization nature. The corresponding chargemore » density equals {rho}{sub Pol} = {del} {center_dot} P, where P is an effective polarization vector that depends on the quadrupole moment and spin-orbit interaction. This density oscillates in space, producing zero contribution to the total charge.« less
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  • The Ky1, Ky2, and Ky3 centers are the dominant defects produced in the electron-irradiated p-type 6H-SiC crystals. The electron paramagnetic resonance study of these defects has been performed in the temperature range of 4.2-300 K at X, K, and Q bands. The centers are characterized by the fourfold silicon coordination established on a basis of the observed hyperfine structure. At low temperatures both Ky1 and Ky2 defects reveal the C{sub S} symmetry that only slightly deviates from the D{sub 2d} one. At high temperatures, the thermally activated reorientation from one Jahn-Teller distortion to the others causes the averaging of themore » Ky1 and Ky2 spectra in such a manner that their spin-Hamiltonians correspond to the axial symmetry. The Ky3 center has axial symmetry in all the temperature range under investigation. Its hyperfine parameters for the first-shell silicon atoms are substantially different from those determined for the Ky1 and Ky2 centers. Based on the density functional theory, the calculations of the electronic structure of a number of fourfold silicon coordinated defects have been carried out for the unambiguous identification of the observed defects through the comparison of experimentally determined and calculated hyperfine parameters. The present study proves an assignment of the Ky1, Ky2, and Ky3 centers to the positively charged carbon vacancy located in two quasicubic and hexagonal sites of the 6H-SiC lattice, respectively. The features of the V{sub C}{sup +} defect related to the multivalley character of its potential energy surface are also discussed. It is shown that this defect can be localized in the minima of different symmetry depending on the occupied lattice site, and these minima are experimentally distinguishable by the values of hyperfine parameters.« less