Thermal neutron induced α-particle reaction on^{64, 65, 67}Zn and⁷⁷Se

The (_nth, α) reaction spectroscopy was done on^{64, 65, 67}zn and⁷⁷Se at the 87 m curved thermal neutron guide of the Grenoble high flux reactor. In each of the⁶⁴Zn(n, α)⁶¹Ni and⁶⁷Ni(n, α)⁶⁴Ni reactions, one line showed up corresponding to an α-particle transition to the first excited state in⁶¹Ni and⁶⁴Ni with σ_α1=11±3 μb and 159±20 μb respectively. In the case of the radioactive⁶⁵Zn(T_1/2=244 d) nucleus, two lines showed up corresponding to the ground state and the first excited state transitions in⁶²Ni with large values of σ_α0=1.0±0.1 b and σ_α1=1.0±0.1 b. For the⁷⁷Se(n, α)⁷⁴Ge reaction, the ground state and first excited transitions were present with σ_α0=940±20 μb and σ_α1 = 30±5 μb respectively. The spin-parity (J^π) of the neutron resonance contributing at thermal energy are discussed.