56,079 research outputs found
Low-lying states in even Gd isotopes studied with five-dimensional collective Hamiltonian based on covariant density functional theory
Five-dimensional collective Hamiltonian based on the covariant density
functional theory has been applied to study the the low-lying states of
even-even Gd isotopes. The shape evolution from Gd to
Gd is presented. The experimental energy spectra and intraband
transition probabilities for the Gd isotopes are reproduced by the
present calculations. The relative ratios in present calculations are
also compared with the available interacting boson model results and
experimental data. It is found that the occupations of neutron
orbital result in the well-deformed prolate shape, and are essential for Gd
isotopes.Comment: 11pages, 10figure
Superspace Formulation in a Three-Algebra Approach to D=3, N=4,5 Superconformal Chern-Simons Matter Theories
We present a superspace formulation of the D=3, N=4,5 superconformal
Chern-Simons Matter theories, with matter supermultiplets valued in a
symplectic 3-algebra. We first construct an N=1 superconformal action, and then
generalize a method used by Gaitto and Witten to enhance the supersymmetry from
N=1 to N=5. By decomposing the N=5 supermultiplets and the symplectic 3-algebra
properly and proposing a new super-potential term, we construct the N=4
superconformal Chern-Simons matter theories in terms of two sets of generators
of a (quaternion) symplectic 3-algebra. The N=4 theories can also be derived by
requiring that the supersymmetry transformations are closed on-shell. The
relationship between the 3-algebras, Lie superalgebras, Lie algebras and
embedding tensors (proposed in [E. A. Bergshoeff, O. Hohm, D. Roest, H.
Samtleben, and E. Sezgin, J. High Energy Phys. 09 (2008) 101.]) is also
clarified. The general N=4,5 superconformal Chern-Simons matter theories in
terms of ordinary Lie algebras can be rederived in our 3-algebra approach. All
known N=4,5 superconformal Chern-Simons matter theories can be recovered in the
present superspace formulation for super-Lie-algebra realization of symplectic
3-algebras.Comment: 37 pages, minor changes, published in PR
Subleading corrections to parity-violating pion photoproduction
We compute the photon asymmetry Bγ for near threshold parity-violating (PV) pion photoproduction through subleading order. We show that subleading contributions involve a new combination of PV couplings not included in previous analyses of hadronic PV. We argue that existing constraints on the leading order contribution to Bγ—obtained from the PV γ-decay of 18F—suggest that the impact of the subleading contributions may be more significant than expected from naturalness arguments
The reduction of the closest disentangled states
We study the closest disentangled state to a given entangled state in any
system (multi-party with any dimension). We obtain the set of equations the
closest disentangled state must satisfy, and show that its reduction is
strongly related to the extremal condition of the local filtering on each
party. Although the equations we obtain are not still tractable, we find some
sufficient conditions for which the closest disentangled state has the same
reduction as the given entangled state. Further, we suggest a prescription to
obtain a tight upper bound of the relative entropy of entanglement in two-qubit
systems.Comment: a crucial error was correcte
Chiral Symmetry and the Parity-Violating Yukawa Coupling
We construct the complete SU(2) parity-violating (PV)
interaction Lagrangian with one derivative, and calculate the chiral
corrections to the PV Yukawa coupling constant through in the leading order of heavy baryon expansion. We
discuss the relationship between the renormalized \hpi, the measured value of
\hpi, and the corresponding quantity calculated microscopically from the
Standard Model four-quark PV interaction.Comment: RevTex, 26 pages + 5 PS figure
The Droplet State and the Compressibility Anomaly in Dilute 2D Electron Systems
We investigate the space distribution of carrier density and the
compressibility of two-dimensional (2D) electron systems by using the local
density approximation. The strong correlation is simulated by the local
exchange and correlation energies. A slowly varied disorder potential is
applied to simulate the disorder effect. We show that the compressibility
anomaly observed in 2D systems which accompanies the metal-insulator transition
can be attributed to the formation of the droplet state due to disorder effect
at low carrier densities.Comment: 4 pages, 3 figure
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