In order to determine the position of the neutron dripline for $Z=4,$ a primary beam of ${}^{40}\mathrm{Ar}$ was accelerated to 140 MeV/nucleon using the newly completed Coupled Cyclotron Facility at the National Superconducting Cyclotron Laboratory at Michigan State University. Neutron-rich fragmentation products emerging from a beryllium production target were separated with the A1900 fragment separator. The isotopes ${}^{6,8}\mathrm{He},$ ${}^{9,11}\mathrm{Li},$ ${}^{12,14}\mathrm{Be},$ ${}^{17,19}\mathrm{B},$ and ${}^{20}\mathrm{C}$ were identified using time-of-flight and energy-loss information, but no events of ${}^{16}\mathrm{Be}$ were recorded.

• Received 11 December 2002

DOI:https://doi.org/10.1103/PhysRevC.67.061303