The Mass Programme at GANIL Using the CSS2 and CIME Cyclotrons

The mass-measurement programme at GANIL aims to measure the masses of heavy nuclei close to the N=Zline which is the ideal region to study neutron-proton pairing. An original direct time-of-flight mass-measurement method was developed at GANIL which uses the CSS2 cyclotron as a high-resolution spectrometer. The masses of ions of A=68,76,80 and 100 have been measured with a precision of a few 10−6. Mass measurements will be performed with the new CIME cyclotron of SPIRAL using a similar method based on the measurement of the phase of the accelerated ions for different radio-frequencies. A recently approved experiment will help develop this new technique and aims to measure the mass of 31Ar radioactive nuclei with a precision of 10−6.