Precision lifetimes of positron emitters,²⁵Al, ²⁹P, ³³Cl and ⁴¹Sc, and ft values of mirror β decays

Half lives of positron decays of²⁵Al, ²⁹P, ³³C1 and ⁴¹Sc have been determined to be (7.177±0.023)s, (4.149+0.005)s, (2.513±0.004)s, and (0.591±0.005)s, respectively. Each object activity was produced at a resonance energy of the proton-capture reaction to minimize the contamination due to other activities. The ft values of mirror β decay for 11⩽A⩽41, which were calculated by using a refined wave function of electron and the recent data, are presented.