Evidence for Different Freeze-Out Radii of High- and Low-Energy Pions Emitted in Au+Au Collisions at 1 GeV/nucleon

A. Wagner; C. Müntz; H. Oeschler; C. Sturm; R. Barth; M. Cieślak; M. Dȩbowski; E. Grosse; P. Koczo{ń}; M. Mang; D. Miśkowiec; R. Schicker; E. Schwab; P. Senger; P. Beckerle; D. Brill; Y. Shin; H. Ströbele; W. Waluś; B. Kohlmeyer; F. Pühlhofer; J. Speer; K. Völkel

doi:10.1016/s0370-2693(97)01549-9

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arXiv · nucl-ex/9712004

Evidence for Different Freeze-Out Radii of High- and Low-Energy Pions Emitted in Au+Au Collisions at 1 GeV/nucleon

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Abstract

Double differential production cross sections of negative and positive pions and the number of participating protons have been measured in central Au+Au collisions at 1 GeV per nucleon incident energy. At low pion energies the pi^- yield is strongly enhanced over the pi^+ yield. The energy dependence of the pi^-/pi^+ ratio is assigned to the Coulomb interaction of the charged pions with the protons in the reaction zone. The deduced Coulomb potential increases with increasing pion c.m. energy. This behavior indicates different freeze-out radii for different pion energies in the c.m.~frame.

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A. Wagner, C. Müntz, H. Oeschler, C. Sturm, R. Barth, M. Cieślak, M. Dȩbowski, E. Grosse, P. Koczo{ń}, M. Mang, D. Miśkowiec, R. Schicker, E. Schwab, P. Senger, P. Beckerle, D. Brill, Y. Shin, H. Ströbele, W. Waluś, B. Kohlmeyer, F. Pühlhofer, J. Speer, K. Völkel. 1997-12-11. Evidence for Different Freeze-Out Radii of High- and Low-Energy Pions Emitted in Au+Au Collisions at 1 GeV/nucleon. https://doi.org/10.1016/s0370-2693(97)01549-9

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