The recently suggested interpretation of the universal hadronic freeze-out temperature T_f ~ 170 Mev - found for all high energy scattering processes that produce hadrons: e+ e-, p p, p anti-p, pi p, etc. and N N (heavy-ion collisions) - as a Unruh t
emperature triggers here the search for the gravitational black-hole that in its near-horizon approximation better simulates this hadronic phenomenon. To identify such a black-hole we begin our gravity-gauge theory phenomenologies matching by asking the question: which black-hole behind that Rindler horizon could reproduce the experimental behavior of T_f (sqrt{s}) in N N, where sqrt{s} is the collision energy. Provided certain natural assumptions hold, we show that the exact string black-hole turns out to be the best candidate (as it fits the available data on T_f (sqrt{s})) and that its limiting case, the Witten black-hole, is the unique candidate to explain the constant T_f for all elementary scattering processes at large energy. We also are able to propose an effective description of the screening of the hadronic string tension sigma(mu_b) due to the baryon density effects on T_f.
