Composite soliton solution with baryon number B = 0 but Hopf index H = 1 in the Skyrme model

In the SU(2) x SU(2) Skyrme model, one can treat the topological soliton-Skyrmion having baryon number B = 1 as baryon. In this paper, the authors have used Skyrmion and anti-Skyrmion to construct a kind of composite soliton solution having baryon number B = 0 but Hopf index H = 1 and have found its mass depends on a dimensionless parameter p(0 < p ≤ 1). In addition, we have also discussed the quantization of the soliton and the probability of treating the quantized soliton as baryonium