First TASCA Commissioning Experiments in the Small Image Size Mode

Ion-optical calculations with the code TRANSPORT (TRANS) (test reaction 235 MeV Ca + UF4 (0.5 mg/cm) ==> 112) were used as a first step to optimize and to built TASCA [1,2]. As a next step the TASCA Monte-Carlo SIMulation program (TSIM) was developed and was applied [3] showing good agreement with previous results. Results for TASCA in the Small Image Size Mode (SIM) are compared in Table 1. Smaller values obtained with the more realistic TSIM are mainly due to straggling and to charge-exchange processes in the gas. A typical product distribution in the focal plane is shown in Figure 1. Based on these simulations we opted for a window with 3 cm in diameter for the SIM Recoil Transfer Chamber (RTC) [4].