Search

Your search keyword '"Elementary-Particles"' showing total 4 results
Start Over Descriptor "Elementary-Particles"
4 results on '"Elementary-Particles"'

1. Relativistic coupled-cluster study of RaF as a candidate for parity and time reversal violating interaction

Author

Malaya K. Nayak, Sourav Pal, Sudip Sasmal, Nayana Vaval, and Himadri Pathak

Subjects
Atoms, Odd, Atomic Physics (physics.atom-ph), FOS: Physical sciences, Electron, 01 natural sciences, Physics - Atomic Physics, Physics - Chemical Physics, Electric field, 0103 physical sciences, Hyperfine-Structure, Ybf Molecule, 010306 general physics, Hyperfine structure, Physics, Chemical Physics (physics.chem-ph), Elementary-Particles, 010304 chemical physics, Enhancement, Parity (physics), Wave-Function, Electric-Dipole Moment, Electric dipole moment, Coupled cluster, Unpaired electron, Analytic Energy Derivatives, Atomic physics, Ground state, Radium
Abstract

We have employed both Z-vector method and the expectation value approach in the relativistic coupled-cluster framework to calculate the scalar-pseudoscalar (S-PS) P, T -odd interaction constant (W_s) and the effective electric field (Eeff) experienced by the unpaired electron in the ground electronic state of RaF. Further, the magnetic hyperfine structure constants of ^{223}Ra in RaF and ^{223}Ra+ are also calculated and compared with the experimental values wherever available to judge the extent of accuracy obtained in the employed methods. The outcome of our study reveals that the Z-vector method is superior than the expectation value approach in terms of accuracy obtained for the calculation of ground state property. The Z-vector calculation shows that RaF has a high E_eff (52.5 GV/cm) and W_s (141.2 kHz) which makes it a potential candidate for the eEDM experiment., Comment: 8 pages, 3 figures more...

Published
2016
Full Text
View/download PDF

Catalog

Books, media, physical & digital resources
See catalog results

4. Upper Limits on a Possible Gluon Mass

Author

Nussinov, Shmuel, Shrock, Robert, Nussinov, Shmuel, and Shrock, Robert

Abstract

We analyze upper limits on a possible gluon mass, mg. We first discuss various ways to modify quantum chromodynamics to include m(g) not equal 0, including a bare mass, a Higgs mechanism, and dynamical breaking of color SU(3)(c). From an examination of experimental data, we infer an upper limit m(g) < O(1) MeV. As part of our analysis, we show that a claim, hitherto unrefuted in the literature, of a much stronger upper limit on m(g), is invalid. We discuss subtleties in interpreting gluon mass limits in view of the fact that at scales below Lambda(QCD), quantum chromodynamics is strongly coupled, perturbation theory is not reliable, and the physics is not accurately described in terms of the Lagrangian degrees of freedom, including gluons. We also point out a fundamental difference in the behavior of quantum chromodynamics with a nonzero gluon mass and a weakly coupled gauge theory with a gauge boson mass. more...

Published
2010