33,641 research outputs found
Pion structure in a nuclear medium
The structure and electroweak properties of the pion in symmetric nuclear
matter are presented in the framework of the Nambu--Jona-Lasinio model. The
pion is described as a bound state of a dressed quark-antiquark pair governed
by the Bethe-Salpeter equation. For the in-medium current-light-quark
properties we use the quark-meson coupling model, which describes successfully
the properties of hadron in a nuclear medium. We found that the light-quark
condensates, the pion decay constant and pion-quark coupling constant decrease
with increasing nuclear matter density. We then predict the modifications of
the charge radius of the charged pion in nuclear matter.Comment: 4 pages, 6 figures, accepted version for the QNP2018 proceedings, 8th
International Conference on Quarks and Nuclear Physics (QNP2018), November
13-17, 2018, Tsukuba, Ibaraki, Japa
Effects of medium modifications of nucleon form factors on neutrino scattering in dense matter
Effects of the in-medium modifications of nucleon form factors on neutrino
interaction in dense matter are presented by considering both the weak and
electromagnetic interactions of neutrinos with the constituents of the matter.
A relativistic mean field and the quark-meson coupling models are respectively
adopted for the effective nucleon mass and in-medium nucleon form factors. We
calculate the cross-section of neutrino scattering as well as the neutrino mean
free path. We found the cross sections of neutrino scattering in cold nuclear
medium decreases when the in-medium modifications of the nucleon weak and
electromagnetic form factors are taken into account.This reduction results in
the enhancement of the neutrino mean free path, in particular at the baryon
density of around a few times of the normal nuclear matter density.Comment: 4 pages, 2 figures, accepted for the QNP2018 proceedings, a talk
given at QNP2018, 8th International Conference on Quarks and Nuclear Physics
(QNP2018), November 13-17, 2018, Tsukuba, Ibaraki, Japa
On the sign of the pi-rho-omega coupling constant
It is shown that the relative sign between the and
coupling constants can be determined most sensitively from production
processes in collisions. Recent data on these reactions clearly favor the
sign of the coupling constant which is opposite to that
inferred from studies of the photoproduction reaction in combination with the
vector meson dominance assumption and used by many authors. Implication of this
finding in the description of other reactions is discussed.Comment: 6 pages, 4 figures, REVTeX, to be published in Phys. Lett.
Higher Derivative CP(N) Model and Quantization of the Induced Chern-Simons Term
We consider higher derivative CP(N) model in 2+1 dimensions with the
Wess-Zumino-Witten term and the topological current density squared term. We
quantize the theory by using the auxiliary gauge field formulation in the path
integral method and prove that the extended model remains renormalizable in the
large N limit. We find that the Maxwell-Chern-Simons theory is dynamically
induced in the large N effective action at a nontrivial UV fixed point. The
quantization of the Chern-Simons term is also discussed.Comment: 8 pages, no figure, a minor change in abstract, added Comments on the
quantization of the Chern-Simons term whose coefficient is also corrected,
and some references are added. Some typos are corrected. Added a new
paragraph checking the equivalence between (3) and (5), and a related
referenc
Production Performance of Broilers fed different Feed Additives
A study of the production performance of broilers fed different feed additives (Lactozyme, Jimplex,
and Nutrifac), indicated no significant difference among the treatment means concerning feed consumption
and feed conversion. For weight gain, there was a significant difference (P<0.05) between the
Jimplex and Control groups. Broilers from the Jimplex group were 5.92% heavier and had a higher income
over feed cost per bird by $0.13 when compared to those from the con trol group at 63 days of age
The use of "Pruteen1" in broiler diets
A study, involving 1,200 birds., was conducted to compare the performance of birds fed pruteenbased
and commercial diets. The mean individual feed intake, weight gain and feed conversion ratio (F.eR.)
of birds fed the pruteen-based diet were 4673.8 g, 2172.3 g and 2.15 respectively, whereas in those fed
the commercial diet they were 4832.5 g, 2151.8 g and 2.25 respectively. Birds fed the pruteen-based diet
consumed significantly less feed and had better F. C.R. (P < 0.05). However the difference of 20.5 g in
weight gain/bird in favour of the pruteen-based diet was not found to be significant. Mortality figures of
4.5% and 3.8% respectively of birds fed pruteen-based and commercial diets were considered normal.
There was a difference of $0. 0878 in the feed cost/bird in favour of the pruteen-based diet
Stability and asymptotic behavior of periodic traveling wave solutions of viscous conservation laws in several dimensions
Under natural spectral stability assumptions motivated by previous
investigations of the associated spectral stability problem, we determine sharp
estimates on the linearized solution operator about a multidimensional
planar periodic wave of a system of conservation laws with viscosity, yielding
linearized stability for all and dimensions and nonlinear stability and
-asymptotic behavior for and . The behavior can in
general be rather complicated, involving both convective (i.e., wave-like) and
diffusive effects
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