Long-time behavior for the Cauchy problem of the 3-component Manakov system

In this work, the Riemann-Hilbert problem for the 3-component Manakov system is formulated on the basis of the corresponding $4\times 4$ matrix spectral problem. Furthermore, by applying the nonlinear steepest descent techniques to an associated $4\times 4$ matrix valued Riemann-Hilbert problem, we can find leading-order asymptotics for the Cauchy problem of the 3-component Manakov system.