Strongly coupled large-angle stimulated Raman scattering (LA SRS) of a short
intense laser pulse proceeds in a plane plasma-filled capillary differently
than in a plasma with open boundaries. Oblique mirror reflections off capillary
walls partly suppress the lateral convection of scattered radiation and
increase the growth rate of the instability: the convective gain of the LA SRS
falls with an angle much slower than in an unbounded plasma and even for the
near-forward SRS can be close to that of the direct backscatter. The long-term
evolution of LA SRS in the interior of the capillary is dominated by
quasi-one-dimensional leaky modes, whose damping is related to the transmission
of electromagnetic waves through capillary walls.Comment: 11 pages, 6 figures; to be submitted to Physics of Plasma