No abstract

Starting from an asymptotically correct three-body Coulomb wave-function, we determine the effect of Coulomb final state interaction on the three-particle Bose-Einstein correlation function of similarly charged particles. We numerically estimate that the Riverside approximation is not precise enough to determine the three-body Coulomb correction factor in the correlation function, if the characteristic HBT radius parameter is 5 -10 fm, which is the range of interest in high-energy heavy ion physics.

Abstract. Few-body methods provide very useful tools to solve different problems important for nuclear astrophysics. Some of them are discussed below. TRIPLE COLLISIONSBinary collisions are dominant in stellar environments. But since nuclear reactions occur in a stellar plasma, it is important to estimate the impact of the medium on the elementary processes. The dynamic effect of the medium is to produce triple nonradiative collisions. To calculate the reaction rates for such processes, we use a genuine threebody Coulomb scattering wave function, which is exact in the asymptotic region where two particles are close to each other and far away from the third (spectator) particle. We have estimated reaction rates of 7 Be´ep eµ 8 B and 7 Be´pp pµ 8 B triple collisions leading to the nonradiative formation of 8 B. For solar core conditions we find that the triple collision rates for 7 Be´ep eµ 8 B and 7 Be´pp pµ 8 B are approximately 10 5 and 10 12 of that for the binary one 7 Be´p γµ 8 B. Triple collisions play a minor role in stellar matter unless temperatures and densities are high. COULOMB BREAKUPIt is very difficult, or often impossible, to measure under lab conditions nuclear cross sections at stellar energies. That is why different indirect techniques, such as Coulomb breakup reactions, are useful for getting at the desired astrophysical information. This information can be distorted by the final-state three-body Coulomb interaction (postdecay Coulomb acceleration). A correct treatment of the final-state rescattering requires the use of a genuine scattering wave function for three charged particles in the contin-

No abstract

No abstract

We present the first results of a calculation of kinematically complete differential cross sections for the proton-induced deuteron breakup reaction, obtained by using a three-body formalism based on momentum space integral equations which correctly takes into account the Coulomb repulsion between the two protons. Comparison with experimental data is made.PACS number(s): 25.10.+s, 03.65.Nk, 21.45.+v, 25.40. Ep

We present results of the first calculation of the double differential cross section for the 208Pb(8B,(7)Bep)208Pb Coulomb breakup reaction which treats the postdecay acceleration of the ejectiles within a genuine three-body approach. From this we conclude that, in order to minimize postdecay Coulomb acceleration effects, experiments should be performed at as small as possible scattering angles, not too low 7Be-p relative energies, and high incident energy.

By using the (in general complex) phase shifts for elastic neutron-deuteron scattering in the quartet channel, calculated by means of the exact few-body theory, as input in the fixed-I inverse scattering theory of Marchenko, we construct equivalent local two-body potentials. The latter, though being complex and energy independent, nevertheless reproduce the input phase shifts, which are real below and complex above the deuteron breakup threshold, to a high accuracy. It is even more remarkable that the scattering wave functions (with real boundary conditions) for energies in the elastic regime, calculated with these potentials, are real outside the range of the force, and to a very good approximation real also in the interior region.