Measurements of projectile-like Be8 and B9 production in 200-400 MeV/nucleon C12 on water

We have studied the production of the projectile-like fragments Be8 and B9 produced in interactions of 200 to 400 MeV/nucleon carbon ions with water, using emulsion detectors. In this Brief Report we present the first published production cross section of the projectile-like fragment B9 in the energy region above 100 MeV/nucleon. The measured production cross sections of these nuclides were compared to calculations using a semiempirical model. We found that the measured cross sections deviate from the calculated values by a factor up to about six. This information is of importance for benchmarking and improving heavy ion nuclear reaction models.