Beta decay half-lives of neutron rich Ti-Co isotopes around N=40

The neutron-rich 57-59Ti, 59-62V, 61-64Cr, 63-66Mn, 65-68Fe, 67-70Co have been produced at GANIL via interactions of a 60.4 MeV/u 86Kr34+ with a 58Ni target. They have been separated by the doubly achromatic spectrometer LISE3. Beta-decay half-lives have been determined for all produced nuclei, and subsequent γ-rays have been observed for the most efficiently produced nuclei. The measured half-lives of vanadium and chromium isotopes are compared to QRPA calculations using ground states deformations from the FRDM or ETFSI models. In an astrophysical context, the short half-lives of 58Ti and 64Cr indicate that these nuclei are potential r-process progenitors, after β-decay, of 58Fe and 64Ni in certain inclusions of meteorites