2,292 research outputs found
Leading and higher twists in proton, neutron and deuteron unpolarized structure functions
We summarize the results of a recent global analysis of proton and deuteron
F2 structure function world data performed over a large range of kinematics,
including recent measurements done at JLab with the CLAS detector. From these
data the lowest moments (n <= 10) of the unpolarized structure functions are
determined with good statistics and systematics. The Q**2 evolution of the
extracted moments is analyzed in terms of an OPE based twist expansion, taking
into account soft-gluon effects at large x. A clean separation among the
Leading and Higher-Twist terms is achieved. By combining proton and deuteron
measurements the lowest moments of the neutron F2 structure function are
determined and its leading twist term is extracted. Particular attention is
paid to nuclear effects in the deuteron, which become increasingly important
for the higher moments. Our results for the non-singlet, isovector (p - n)
combination of the leading twist moments are used to test recent lattice
simulations. We also determine the lowest few moments of the higher twist
contributions, and find these to be approximately isospin independent,
suggesting the possible dominance of ud correlations over uu and dd in the
nucleon.Comment: 8 pages, 4 figures; to appear in the Proceedings of the IVth
International Conference on Quark and Nuclear Physics (QNP06), Madrid
(Spain), June 5-10, 200
Vortex Mass in a Superfluid
We consider the inertial mass of a vortex in a superfluid. We obtain a vortex
mass that is well defined and is determined microscopically and
self-consistently by the elementary excitation energy of the kelvon
quasiparticle localised within the vortex core. The obtained result for the
vortex mass is found to be consistent with experimental observations on
superfluid quantum gases and vortex rings in water. We propose a method to
measure the inertial rest mass and Berry phase of a vortex in superfluid Bose
and Fermi gases.Comment: 12 pages, 1 figur
Synthetic charge-flux quantum liquids
We apply rotating optical flux lattices to spinor Bose-Einstein condensates.
Distinct quantum states emerge for fractional ratios of vortex charge density
to optical flux density. We exhibit the calculated charge-flux states and
discuss their topological structure and experimental signatures.Comment: 4 pages, 3 figure
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