The SU(n) invariant massive Thirring model with boundary reflection

We study the SU(n) invariant massive Thirring model with boundary reflection. Our approach is based on the free field approach. We construct the free field realizations of the boundary state and its dual. For an application of these realizations, we present integral representations for the form factors of the local operators.Comment: LaTEX2e file, 27 page

Uq(sl^n)U_q(\hat{sl}_n)-analog of the XXZ chain with a boundary

We study $U_q(\hat{sl}_n)$ analog of the XXZ spin chain with a boundary magnetic field h. We construct explicit bosonic formulas of the vacuum vector and the dual vacuum vector with a boundary magnetic field. We derive integral formulas of the correlation functions.Comment: 24 pages, LaTEX2

Type II vertex operators for the An−1(1)A_{n-1}^{(1)} face model

Presented is a free boson representation of the type II vertex operators for the $A_{n-1}^{(1)}$ face model. Using the bosonization, we derive some properties of the type II vertex operators, such as commutation, inversion and duality relations.Comment: 20 pages, LaTEX 2

Free field approach to diagonalization of boundary transfer matrix : recent advances

We diagonalize infinitely many commuting operators $T_B(z)$. We call these operators $T_B(z)$ the boundary transfer matrix associated with the quantum group and the elliptic quantum group. The boundary transfer matrix is related to the solvable model with a boundary. When we diagonalize the boundary transfer matrix, we can calculate the correlation functions for the solvable model with a boundary. We review the free field approach to diagonalization of the boundary transfer matrix $T_B(z)$ associated with $U_q(A_2^{(2)})$ and $U_{q,p}(\hat{sl_N})$. We construct the free field realizations of the eigenvectors of the boundary transfer matrix $T_B(z)$. This paper includes new unpublished formula of the eigenvector for $U_q(A_2^{(2)})$. It is thought that this diagonalization method can be extended to more general quantum group $U_q(g)$ and elliptic quantum group $U_{q,p}(g)$.Comment: To appear in Group 28 : Group Theoretical Method in Physic

Boundary shape identification problems in two-dimensional domains related to thermal testing of materials

The identification of the geometrical structure of the system boundary for a two-dimensional diffusion system is reported. The domain identification problem treated here is converted into an optimization problem based on a fit-to-data criterion and theoretical convergence results for approximate identification techniques are discussed. Results of numerical experiments to demonstrate the efficacy of the theoretical ideas are reported

New Dissipation Relaxation Phenomenon in Oscillating Solid He-4

We describe the first observations on the time-dependent dissipation when the drive level of a torsional oscillator containing solid He-4 is abruptly changed. The relaxation of dissipation in solid He-4 shows rich dynamical behavior including exponential and logarithmic time-dependent decays, hysteresis, and memory effects.Comment: 4 pages, 4 figure

Oscillation Frequency Dependence of Non-Classical Rotation Inertia of Solid 4^4He

The non-classical rotational inertia fraction of the identical cylindrical solid $^4$He below 300 mK is studied at 496 and 1173 Hz by a double resonance torsional oscillator. Below 35 mK, the fraction is the same at sufficiently low rim velocities. Above 35 mK, the fraction is greater for the higher than the lower mode. The dissipation peak of the lower mode occurs at a temperature $\sim$ 4 mK lower than that of the higher mode. The drive dependence of the two modes shows that the reduction of the fraction is characterized by critical velocity, \textit{not} amplitude nor acceleration.Comment: 4 pages, 4 figure

Spin Fluid Dynamics Observed by Magnetic Fountain Effect and Mechano-Spin Effect in the Ferromagnetic Superfluid 3^3He A1_1 Phase

Systematic observations of the magnetically generated fountain pressure in the superfluid $^3$He A$_1$ have been carried out in a newly built apparatus designed to reduce the effect of thermal gradients. In the same apparatus, mechanical pumping and filtering of polarized nuclear spins were realized by the pneumatic pumping action of an electrostatically actuated membrane. In both experiments, the measured induced pressure was observed to decay at all temperatures where the A$_1$ phase appeared in magnetic fields up to 13 T and liquid pressures between 1 and 29 bar. The inferred spin relaxation rate tended to increase as the low temperature phase boundary with the A$_2$ phase (T$_{C2}$) was approached. The increase in spin relaxation rate near T$_{C2}$ can be explained by the presence of a minority spin condensate in the A$_1$ phase as predicted by Monien and Tewordt and by the application of the Leggett-Takagi theory of spin relaxation in superfluid $^3$He.Comment: 12 pages, 15 figures, to appear in Physical Review