First Search for B→X_{s}νν[over ¯] Decays. - Abumusabh M; Adachi I; Adamczyk K; Aggarwal L; Ahmed H; Ahn Y; Aihara H; Akopov N; Alghamdi S; Alhakami M; Aloisio A; Althubiti N; et al. (Physical review letters, 2026)