Proton-proton correlations inAr40+197

Abstract

Proton-proton correlations at small relative momenta were measured for 40 Ar+ ,97 Au reactions at El A =200 MeV. Comparing the correlation functions to predictions based on single-particle phase space distributions from microscopic Boltzmann-Uehling-Uhlenbeck and quantum-molecular-dynamics (QMD) simulations, no satisfactory agreement could be established. Calculations utilizing two-particle emission probabilities predicted by the QMD model differ significantly from the single-particle calculations and are much closer to the experimental observations at El A =200 MeV, potentially signaling the importance of the two-particle density for the proton-proton correlation function.

Effects of momentum-dependent nuclear potential on two-nucleon correlation functions and light cluster production in intermediate energy heavy-ion collisions

“…[46,47,48,49] for reviews. In most studies, only the two-proton correlation function is studied [50,51,52,53,54,55,56]. [57,58,59] and have also studied the isospin effects on two-nucleon correlation functions [60].…”

Probing transport theories via two-proton source imaging

“…(2-4) to calculate the theoretical two-proton correlation functions for comparison to the experimental data. This approach has been used to test transport theories by comparisons with two-proton correlations [7][8][9].…”

“…Two-proton correlation functions can provide an important test of transport theory [7][8][9], through their sensitivity to the space-time properties of nuclear reactions [10,9,12]. Initial applications of BUU transport theory to two-proton correlation functions at incident energies of E/A<100 MeV were successful and indicated a significant sensitivity of the calculated correlation functions to the in-medium cross section [7][8][9].…”

“…Recently, this connection has been exploited to place constraints on the equation of state (EOS) of nuclear matter at densities of 2ρ 0 ≤ ρ ≤ 4ρ 0 , where ρ 0 is the nuclear saturation density [5]. Comparable constraints on the EOS at lower densities require a more detailed understanding of transport phenomena at intermediate energies where the delicate interplay of competing sources of pressure, such as collisions via the residual interaction, govern the collision dynamics [6].Two-proton correlation functions can provide an important test of transport theory [7][8][9], through their sensitivity to the space-time properties of nuclear reactions [10,9,12]. Initial applications of BUU transport theory to two-proton correlation functions at incident energies of E/A<100 MeV were successful and indicated a significant sensitivity of the calculated correlation functions to the in-medium cross section [7][8][9].…”

“…The application of such techniques to higher incident energies, however, revealed that there were significant problems in reconciling the stronger calculated correlation functions to the weaker measured ones [9]. These problems, discussed below, led to criticisms that BUU transport theory might be an inadequate theoretical tool for such studies, either due to the neglect of the many body correlations in the BUU approach [8] or due to the neglect of the long lived decays of unstable fragments emitted during a collision [9].In this paper, we largely resolve this issue by showing how more quantitative experimental analyses of two-proton correlations can provide information that can be quantitatively compared to BUU transport theory. We begin by reviewing the basic Koonin-Pratt theoretical approach [10,13] for proton-proton correlation function analyses.…”