2,723 research outputs found
Macroscopic tunneling of a membrane in an optomechanical double-well potential
The macroscopic tunneling of an optomechanical membrane is considered. A
cavity mode which couples quadratically to the membranes position can create
highly tunable adiabatic double-well potentials, which together with the high
Q-factors of such membranes render the observation of macroscopic tunneling
possible. A suitable, pulsed measurement scheme using a linearly coupled mode
of the cavity for the verification of the effect is studied.Comment: 5 pages, 5 figure
Intrinsic quadrupole moment of the nucleon
We address the question of the intrinsic quadrupole moment Q_0 of the nucleon
in various models. All models give a positive intrinsic quadrupole moment for
the proton. This corresponds to a prolate deformation. We also calculate the
intrinsic quadrupole moment of the Delta(1232). All our models lead to a
negative intrinsic quadrupole moment of the Delta corresponding to an oblate
deformation.Comment: 17 pages, 5 figure
Correlated directional atomic clouds via four-heterowave mixing
We investigate the coherence properties of pairs of counter-propagating
atomic clouds, produced in superradiant Rayleigh scattering off atomic
condensates. It is shown that these clouds exhibit long-range spatial coherence
and strong nonclassical density cross-correlations, which make this scheme a
promising candidate for the production of highly directional nonclassically
correlated atomic pulses.Comment: 12 pages, 3 figure
Spin of ground state baryons
We calculate the quark spin contribution to the total angular momentum of
flavor octet and flavor decuplet ground state baryons using a spin-flavor
symmetry based parametrization method of quantum chromodynamics. We find that
third order SU(6) symmetry breaking three-quark operators are necessary to
explain the experimental result Sigma_1=0.32(10). For spin 3/2 decuplet baryons
we predict that the quark spin contribution is Sigma_3=3.93(22), i.e.
considerably larger than their total angular momentum.Comment: 8 page
- …