Characterization of minimal-mass blowup solutions to the focusing mass-critical NLS

Let 𝑑 ≥4 and let u be a global solution to the focusing mass-critical nonlinear Schrödinger equation 𝑖⁢𝑢𝑡 +Δ⁢𝑢 =−|𝑢|4𝑑 ⁢𝑢 with spherically symmetric 𝐻1𝑥 initial data and mass equal to that of the ground state Q. We prove that if u does not scatter, then, up to phase rotation and scaling, u is the solitary wave 𝑒𝑖⁢𝑡⁢𝑄. Combining this result with that of Merle [Duke Math. J., 69 (1993), pp. 427–453], we obtain that in dimensions 𝑑 ≥4, the only spherically symmetric minimal-mass nonscattering solutions are, up to phase rotation and scaling, the pseudoconformal ground state and the ground state solitary wave.