Orbital stability of the smooth solitary wave with nonzero asymptotic value for the mCH equation

This paper is concerned with orbital stability of the smooth solitary wave with nonzero asymptotic value for the mCH equationUnder the parametric conditions a > 0 and , an interesting phenomenon is discovered, that is, for the stability there exist three bifurcation wave speedssuch that the following conclusions hold. When wave speed belongs to the interval (c1, c2) for , the smooth solitary wave is orbitally stable.When wave speed belongs to the interval (c2, c3) for , the smooth solitary wave is orbitally unstable.When wave speed belongs to the interval (c1, c3) for , the smooth solitary wave is orbitally unstable.