M ay 2 00 0 Second Cluster Integral and Excluded Volume Effects for the Pion Gas
نویسندگان
چکیده
Mayer's second cluster integral for the pion gas is calculated in quantum mechanical approach. It is shown that nonresonant repulsive ππ-interactions as well as the finite width of resonances yield important but almost canceling contributions at typical chemical freeze-out temperatures of the hadron gas. The repulsive ππ-interactions to the second cluster integral is identified with Van der Waals excluded volume which is much larger than that calculated with classical mechanics formulae.
منابع مشابه
0 Second Cluster Integral and Excluded Volume Effects for the Pion Gas
The quantum mechanical formula for Mayer's second cluster integral for the gas of relativistic particles with hard-core interaction is derived. The proper pion volume calculated with quantum mechanical formula is found to be an order of magnitude larger than its classical evaluation. The second cluster integral for the pion gas is calculated in quantum mechanical approach with account for both ...
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