Evolution of Wave-Packet Spread under Sequential Scattering of Particles of Unequal Mass

Under assumptions on initial wave-packet spreads and particle interactions, different mass particles scattering off one another will have the product ${\sigma }_i^2{m}_i$ converge to a common value, where ${\sigma }_i$ is the spread and $m_i$ is the mass of the $i$th particle. When this relation is satisfied, kinematic entanglement vanishes.