Measurements of the interaction cross-sections for 14Be and 14,15B as projectiles with a new scheme at RIBLL

We have measured the interaction cross-sections (σI) for light neutron-rich nuclei (14Be, 14,15B) at ∼50A MeV at the Radioactive Ion Beam Line in Lanzhou (RIBLL) in IMP with a new scheme. In this scheme, a carbon reaction target was installed at the intermediate focusing point at RIBLL. This scheme allowed us to identify particles before and after the reaction target unambiguously. However, this scheme might suffer a large loss of transmission efficiency in the second half of RIBLL. We checked this effect by changing the emittance of the RI beams. The results showed that a correction of the transmission efficiency is needed to deduce σI. We performed a Monte Carlo type simulation and tried to deduce σI for the above nuclei. Finally, we obtained reasonable σI although their error bars were fairly large. The results were compared with calculations by an energy-dependent semi-empirical formula.