No abstract

We study properties of effective temperature of nonequilibrium steady states by using the anti-de Sitter spacetime/conformal field theory (AdS/CFT) correspondence. We consider nonequilibrium systems with a constant flow of current along an electric field, in which the current is carried by both the doped charges and those pair created by the electric field.We find that the effective temperature agrees with that of the Langevin systems if we take the limit where the pair creation is negligible. The effect of pair creation raises the effective temperature whereas the current by the doped charges contributes to lower the effective temperature in a wide range of the holographic models.

No abstract

We study the quark structure of the sigma meson through the decay of D 1 (2430) meson by constructing an effective Lagrangian for charmed mesons interacting with light mesons based on the chiral symmetry and heavy quark symmetry. Within the linear realization of the chiral symmetry, we include the P-wave charmed mesons (D 1 (2430), D 0 (2400)) as the chiral partners of (D * , D), and the light scalar mesons as the chiral partner of the pseudoscalar mesons. In the light meson sector, both the qq and qqqq states are incorporated respecting their different U(1) A transformation properties. We predict the D 1 → Dππ decay width with two pions in the I = 0, l = 0 channel, which can be tested in the future experiment. We find that the width increases with the percentage of the qq content in the sigma meson.

No abstract