New measurements of 4H isotope mass in the reactions with radioactive 6He beam and 6Li ions

D(6He, α) reaction cross-sections are measured for the first time at energy E6He=19.3 MeV. Two resonances are found in α-particle spectrum, which resonances correspond to the basic and excited states of 4H nuclear stable isotope which are above the dissociation threshold 4H→t+n for 2.0±0.3 MeV and 5.2±0.5 MeV. An assumption is made that 4H excited state has (d+2n) configuration and 1+ quantum characteristics. A new value of 4H nucleus mass defect, equal to 25.3±0.3 MeV, is derived. 13 refs.; 2 figs