ON GENERAL HIGH-ORDER SOLITONS AND BREATHERS TO A NONLOCAL SCHRODINGER-BOUSSINESQ EQUATION WITH A PERIODIC LINE WAVES BACKGROUND

General high-order soliton and breather solutions to a non-local Schrodinger-Boussinesq (NSB) equation with a periodic line waves (PLWs) background are studied via the bilinear KP-reduction method. We construct tau functions to the NSB equation by restricting tau functions of bilinear equations in the KP hierarchy, which generate arbitrary 2N-soliton and N-breather solutions on a PLWs background in the NSB equation. Based on the asymptotic analysis, the two-soliton solutions are classified into non-degenerate and degenerate two-soliton solutions. The non-degenerate two-soliton has three patterns: two-dark-antidark soliton, two-dark-dark soliton, and two-antidark-antidark soliton. The degenerate two-soliton solution possesses two distinct patterns: the degenerate-antidark soliton and the degenerate-dark soliton. The four-soliton solution on the PLWs background exhibits the superpositions of two two-soliton solutions, and admits three distinct patterns: the non-degenerate four-soliton solution, the two degenerate two-soliton solutions, and the mixture of a degenerate two-soliton solution and a non-degenerate two-soliton solution. The typical dynamical scenarios of one- and two-breather solutions on a PLWs background are analyzed in detail.