High energy heavy-ion collisions are proposed as a novel means to constrain stringently the high density (HD) behavior of nuclear symmetry energy. Within an isospin-dependent hadronic transport model, it is shown for the first time that the isospin asymmetry of the HD nuclear matter formed in high energy heavy-ion collisions is uniquely determined by the HD behavior of the nuclear symmetry energy. Experimental signatures in two sensitive probes, i.e., ${\pi }^{-}$ to ${\pi }^{+}$ ratio and neutron-proton differential collective flow, are also investigated.

• Received 14 December 2001

DOI:https://doi.org/10.1103/PhysRevLett.88.192701