Time-of-flight particle ID: Δt = (L/c)·(√(1+m₁²/p²) − √(1+m₂²/p²)) ≈ L m₁²/(2p²c) for m≪p

Time-of-flight particle identification: two species of mass m₁, m₂ at common momentum p traverse a baseline L with flight-time difference Δt = (L/c)·(1/β₁ − 1/β₂), where β = p/√(p² + m²c²). For m ≪ p this linearises to Δt ≈ L(m₁² −…