Pavel Exner and Diana Barseghyan Spectral estimates for Dirichlet Laplacians on perturbed twisted tubes (182K, pdf) ABSTRACT. We investigate Dirichlet Laplacian in a straight twisted tube of a non-circular cross section, in particular, its discrete spectrum coming from a local slowdown of the twist. We prove a Lieb-Thirring-type estimate for the spectral moments and present two examples illustrating how the bound depends on the tube cross section.