15,102 research outputs found
Precision electromagnetic structure of decuplet baryons in the chiral regime
The electromagnetic properties of the baryon decuplet are calculated in
quenched QCD on a 20^3 x 40 lattice with a lattice spacing of 0.128 fm using
the fat-link irrelevant clover (FLIC) fermion action with quark masses
providing a pion mass as low as 300 MeV. Magnetic moments and charge radii are
extracted from the electric and magnetic form factors for each individual quark
sector. From these, the corresponding baryon properties are constructed. We
present results for the higher order moments of the spin-3/2 baryons, including
the electric quadrupole moment E2 and the magnetic octupole moment M3. The
world's first determination of a non-zero M3 form factor for the Delta baryon
is presented. With these results we provide a conclusive analysis which shows
that decuplet baryons are deformed. We compare the decuplet baryon results from
a similar lattice calculation of the octet baryons. We establish that the
environment sensitivity is far less pronounced in the case of the decuplet
baryons compared to that in the octet baryons. A surprising result is that the
charge radii of the decuplet baryons are generally smaller than that of the
octet baryons. The magnetic moment of the Delta^+ reveals a turn over in the
low quark mass region, making it smaller than the proton magnetic moment. These
results are consistent with the expectations of quenched chiral perturbation
theory. A similar turn over is also noticed in the magnetic moment of the
Sigma^*0, but not for Xi^* where only kaon loops can appear in quenched QCD.
The electric quadrupole moment of the Omega^- baryon is positive when the
negative charge factor is included, and is equal to 0.86 +- 0.12 x 10^-2 fm^2,
indicating an oblate shape.Comment: 30 pages, 32 figure
Platelet-rich plasma and other cellular strategies in orthopedic surgery
The use of biologics in the treatment of musculoskeletal disease has become increasingly more common as research studies continue to provide further elucidation of their mechanisms in healing. Platelet-rich plasma, patches, growth factors, and stem cells are among the many biologics under active investigation and have varying levels of success in augmenting surgical or nonoperative interventions. However, the limitations of these treatments exist, and clear guidelines for their indications and application have yet to be established. Well-designed clinical trials will help determine the appropriate future use of biologics to ensure consistent outcomes
String effects and the distribution of the glue in mesons at finite temperature
The distribution of the gluon action density in mesonic systems is
investigated at finite temperature. The simulations are performed in quenched
QCD for two temperatures below the deconfinment phase. Unlike the gluonic
profiles displayed at T=0, the action density iso-surfaces display a
prolate-spheroid like shape. The curved width profile of the flux-tube is found
to be consistent with the prediction of the free Bosonic string model at large
distances.Comment: 14 pages,10 figure
Spatio-temporal Bounded Noises, and transitions induced by them in solutions of real Ginzburg-Landau model
In this work, we introduce two spatio-temporal colored bounded noises, based
on the zero-dimensional Cai-Lin and Tsallis-Borland noises. We then study and
characterize the dependence of the defined bounded noises on both a temporal
correlation parameter and on a spatial coupling parameter . The
boundedness of these noises has some consequences on their equilibrium
distributions. Indeed in some cases varying may induce a transition
of the distribution of the noise from bimodality to unimodality. With the aim
to study the role played by bounded noises on nonlinear dynamical systems, we
investigate the behavior of the real Ginzburg-Landau time-varying model
additively perturbed by such noises. The observed phase transitions
phenomenology is quite different from the one observed when the perturbations
are unbounded. In particular, we observed an inverse "order-to-disorder"
transition, and a re-entrant transition, with dependence on the specific type
of bounded noise.Comment: 12 (main text)+5 (supplementary) page
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