P.L. Kapitza Institute for Physical Problems, Moscow, Russia
Received November 22, 2007
We consider reflection of first and second sound waves by a rigid flat wall in helium II. A nontrivial dependence of the reflection coefficients on the angle of incidence is obtained. Sound conversion is predicted
at slanted incidence.
PACS: 67.25.dg Transport, hydrodynamics, and superflow; PACS: 67.25.dt Sound and excitations; PACS: 67.55.dm Two-fluid model; phenomenology.