Theory and observations of slow-mode solitons in space plasmas.

A generalized model for one-dimensional magnetosonic structures of large amplitude in space plasmas is presented. The model is verified with multipoint measurements on Cluster satellites in the magnetosheath and the boundary layer under conditions of plasma beta (plasma/magnetic pressure) between 0.1-10. We demonstrate good agreement between the model and observations of large amplitude structures and wave trains, which represent increases of magnetic field and plasma density 2-5 times the ambient values, or local decreases (holes) by approximately (50-80)%. Theoretically derived polarization and propagation properties of slow-mode nonlinear structures are also in agreement with in situ measurements in space.