  We studied the formation of Y-junctions for transonic elastic strings. In
particular, using the gen-eral solution for these strings, which is described
by left- and right-moving modes, we obtained thedynamics of kinks and
Y-junctions. Considering the linearized ansatz for straight strings, we
con-structed the parameter region space for which the formation of Y-junctions
due to strings collisionsis allowed.
