A 32-phoswich detector array has been used in conjunction with two Si-telescopes to detect, in coincidence, light and projectile-like fragments produced in the reaction 14N + 197Au at 560 MeV. Inclusive and semi-exclusive cross sections are given. Angular correlations and invariant cross-section velocity distributions of light particles in coincidence with projectile-like fragments are used to deduce the dominant reaction mechanisms. The transfer of nucleons to the target and sequential breakup of the quasi-projectile with or without pickup of target nucleons are clearly seen. Some evidence is found for a prompt breakup of the projectile into 10B + α followed by a dissipative interaction of the heavy fragment with the target.
A strangelet search in Si+Pt and Au+Pt collisions at alternating-gradient synchrotron (AGS) energies, using a focusing spectrometer, sensitive to mass per charge of 3-14 GeV/c2 was conducted during the 1992 and 1993 heavy ion runs at the AGS. The null results thereof are presented as upper limits on the invariant production cross section, in the range of 10−5-10−4 mb c3/GeV2, and model dependent sensitivity limits in the range of 10−7-10−5 per collision. Measurements of the production cross sections of several nonstrange nuclear systems, from p to Be7 and Li8, the background of the strangelet search, are also presented.
We report on measurements by the E864 experiment at the BNL-AGS of the yields of light nuclei in collisions of Au(197) with beam momentum of 11.5 A GeV/c on targets of Pb(208) and Pt(197). The yields are reported for nuclei with baryon number A=1 up to A=7, and typically cover a rapidity range from y(cm) to y(cm)+1 and a transverse momentum range of approximately 0.1 < p(T)/A < 0.5 GeV/c. We calculate coalescence scale factors B(A) from which we extract model dependent source dimensions and collective flow velocities. We also examine the dependences of the yields on baryon number, spin, and isospin of the produced nuclei.
Forum