In this experiment, the primary beam of 78 Kr 19+ was successively accelerated by the sector-focusing cyclotron (SFC) and heavy-ion synchrotron (CSRm) and then extracted to bombard the production target to produce exotic nuclei. Beams of various nuclear species including 63 Ge, 64,65 As and 66,67 Se were collected and separated with RIBLL2 and injected into CSRe, where the masses of the nuclei of interest were determined with high precision through the measurement of their revolution times and velocities applying B p -IMS spectrometry 33 , 34 . The separated-sector cyclotron (SSC) was not used in this experiment. The inset shows a schematic of the ToF detector. The secondary electrons released from the carbon foil are guided by the crossed electrostatic and magnetic fields to the MCP. The electrostatic field E is produced by three potential plates, namely, carbon foil, MCP and equalizing ring, and the magnetic field B is produced by an external dipole magnet.
