Pion correlation from Skyrmion-AntiSkyrmion annihilation

We study two pion correlations from Skyrmion and antiSkyrmion collision, using the product ansatz and an approximate random grooming method for nucleon projection. The spatial-isospin coupling inherent in the Skyrme model, along with empirical averages, leads to correlations not only among pions of like charges but also among unlike charge types.Comment: uuencoded files of REVTeX and postscript, 18 pages including 2 figures, submitted to Phys.Rev.

Nucleon-Antinucleon Interaction from the Skyrme Model

We calculate the nucleon-antinucleon static potential in the Skyrme model using the product ansatz and including some finite $N_C$ (number of colors) corrections. The mid and long range part of the spin-spin and tensor force are correctly given in both iso-spin channels while the central interaction has insufficient mid-range attraction. This is a well known problem of the product ansatz that should be repaired with better Skyrme dynamics.Comment: uuencoded files of revtex and postscript, 21 pages including 8 figures, submitted to Phys.Rev.

Nucleon-Antinucleon Interaction from the Skyrme Model: II. Beyond the Product Ansatz

We calculate the full static interaction of a Skyrmion and an anti-Skyrmion as a function of separation and relative grooming. From this, using projection methods and Born-Oppenheimer mixing, we obtain the nucleon antinucleon interaction. We find agreement with the major features of the empirical interaction including the strong central attraction and the sharp onset of annihilation at about 1 fm.Comment: files of latex and postscript, including 1 tables and 9 figure

Communication and Monetary Policy

One role of monetary policy is to coordinate expectations in the economy and greater transparency of monetary policy may lead to greater coordination. But if transparentCommunication, Monetary policy, Transparency, Common knowledge

The theoretical instability strip of M dwarf stars

The overstability of the fundamental radial mode in M dwarf models was theoretically predicted by Rodr\'iguez-L\'opez et al. (2012). The periods were found to be in the ranges ~25-40 min and ~4-8 h, depending on stellar age and excitation mechanism. We have extended our initial M dwarf model grid in mass, metallicity, and mixing length parameter. We have also considered models with boundary conditions from PHOENIX NextGen atmospheres to test their influence on the pulsation spectra. We find instability of non-radial modes with radial orders up to k=3, degree l=0-3, including p and g modes, with the period range extending from 20 min up to 11 h. Furthermore, we find theoretical evidence of the potential of M dwarfs as solar-like oscillators.Comment: 11 pages, 7 figures, 3 tables + 3 appendix tables; accepted for publication in MNRAS (December 3, 2013

Plateau insulator transition in graphene

The quantum Hall effect in a single-layer graphene sample is studied in strong magnetic fields up to 28 T. Our measurements reveal the existence of a metal- insulator transition from filling factor $\nu=-2$ to $\nu=0$. The value of the universal scaling exponent is found to be $\kappa=0.57$ in graphene and therefore in a truly two-dimensional system. This value of $\kappa$ is in agreement with the accepted universal value for the plateau-insulator transitions in standard quasi two-dimensional electron and hole gases.Comment: 10 pages, 5 figure