We present a numerical computation of overlaps in mass quenches in
sine-Gordon quantum field theory using truncated conformal space approach
(TCSA). To improve the cut-off dependence of the method, we use a novel running
coupling definition which has a general applicability in free boson TCSA. The
numerical results are used to confirm the validity of a previously proposed
analytical Ansatz for the initial state in the sinh-Gordon quench.Comment: 13 pages, 4 pdf figure
