Antiproton production in p-nucleus and nucleus-nucleus collisions within a relativistic transport approach

Abstract

The production of antiprotons in proton-nucleus and nucleus-nucleus reactions is calculated within the relativistic BUU approach employing proper selfenergies for the baryons and antiprotons and treating thep annihilation nonperturbatively. The differential cross section for the antiprotons is found to be very sensitive to thep selfenergy adopted. A detailed comparison with the available experimental data for p-nucleus and nucleus-nucleus reactions shows that the antiproton feels a moderately attractive mean-field at normal nuclear matter density ρ 0 which is in line with a dispersive potential extracted from the free annihilation cross section. * [

Recent Progress in Quantum Hadrodynamics

“…The role of the Dirac sea in such collisions is discussed in [Ju92]. The production of kaons is examined in [Fa93,Fa93a,Fa94] and of antinucleons, in [Te93,Te94,Li94].…”

Subthreshold antiproton production in pC, dC and C reactions

“…Most of the descriptions proposed so far are based on transport calculations [13][14][15][16][17][18][19][20][21][22], thermodynamical considerations [23][24][25][26] or multi-particle interactions [27] and are devoted to proton and/or heavy-ion induced reactions. By measuring lightion-induced subthresholdp production the KEK group [12] intended to provide an experimental test for models in this transition region between proton and heavy-ioninduced reactions.…”

Multi-nucleon mechanism for subthreshold antiproton production in proton-nucleus reactions

“…The curves are analogous to a. Data points adapted from [6,17]. These results have been obtained with (15) using the free antiproton mass.…”

“…Several recent publications include in-medium changes of hadronic properties [17][18][19] but so far they have not reached consensus in their conclusions concerning the p self-energy in matter. In all these calculations a major uncertainty (apart from the elementary/5 production cross section) is/5 reabsorption.…”

“…In all these calculations a major uncertainty (apart from the elementary/5 production cross section) is/5 reabsorption. The/5 survival rates range (in the absence of/5 selfenergies) for the Si + Si system from 1% in [17] to 4% in [19], a factor of 4 difference. There is general agreement nevertheless on the dominant role played by the A resonance in the/5 production process and on the necessity to introduce quasiparticle properties for both nucleons and/5's in the medium.…”