  The apparent thermalization of the particles produced in hadronic collisions
can be obtained by quantum entanglement of the partons of the initial state
once a fast hard collision is produced. The scale of the hard collision is
related to the thermal temperature. As the probability distribution of these
events is of the form $np(n)$, as a consequence, the von Neumann entropy is
larger than in the minimum bias case. The leading contribution to this entropy
comes from the logarithm of the number of partons $n$, all with equal
probability, making maximal the entropy. In addition there is another
contribution related to the width of the parton multiplicity. Asymptotically,
the entanglement entropy becomes the logarithm of $\sqrt{n}$, indicating that
the number of microstates changes with energy from $n$ to $\sqrt{n}$.
