143,398 research outputs found
Scalar and vector meson propagation in asymmetric nuclear matter
The propagation of the scalar (\sigma and \delta) and vector (\omega and
\rho) mesons in an iso-asymmetric nuclear matter is studied in detail, using
the Walecka model. We calculate the invariant masses and spectral functions of
the mesons, including the effect of meson mixing. At finite density, the mixing
effect is quite important in the propagation of the scalar and (longitudinal)
vector mesons. In the \sigma channel, we find a three-peak structure in the
spectral function, caused by the mixing effect.Comment: 10 pages, 2 figures. Fig.2 is given separately. High resolution
images are available on reques
On the Solution of Topological Landau-Ginzburg Models with
The solution is given for the topological matter model whose underlying
conformal theory has Landau-Ginzburg model W=-\qa (x^4 +y^4)+\af x^2y^2.
While consistency conditions are used to solve it, this model is probably at
the limit of such techniques. By using the flatness of the metric of the space
of coupling constants I rederive the differential equation that relates the
parameter \af\ to the flat coordinate . This simpler method is also applied
to the -model.Comment: 7p
Naturalness in the quark-meson coupling model
The quark-meson coupling (QMC) model is examined using Georgi's ``naive
dimensional analysis''. We argue that the QMC model is quite natural as an
effective field theory for nuclei.Comment: 11pages, no fig., submitted to Phys. Lett.
Flavour asymmetry of anti-quarks in nuclei
A novel nuclear effect on the flavour asymmetry of anti-quarks in the nucleon
bound in a nucleus is discussed in terms of the meson cloud model and the Pauli
exclusion principle. It is expected that the flavour asymmetry is enhanced in a
nucleus.Comment: 3 pages, Euro. Phys. J. A in pres
Is english our lingua franca or the native speaker's property? The native speaker orientation among middle school students in Japan
This paper reports the first empirical study to date that sought to examine the native speaker orientation among middle school EFL students in Japan. To this end, this preliminary study measured their language attitudes in this respect addressing age-stratified and gender variations. The data was elicited from an attitude survey with 318 eighth and ninth graders at a public middle school. The findings suggest that the students gave the highest evaluations to native than to nonnative varieties of English. Second, they opted for learning English for its currency and utility in the English as a native language setting, rather than for its transnational function as a lingua franca. Lastly, the finding indicated a possible developmental trajectory of their native speaker orientation
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