Higher order intercommutations in cosmic string collisions.

We report the first observation of multiple intercommutation (more than two successive reconnections) of Abelian Higgs cosmic strings at ultrahigh collision speeds, and the formation of "kink trains" with up to four closely spaced left- or right-moving kinks, in the deep type-II regime 16 ≤ β ≤ 64 (where β=m(scalar)2/m(gauge)2). The minimum critical speed for double reconnection goes down from ∼0.98c at β = 1 to ∼0.