Development of a new type of manganese bath for determination of neutron emission rate of a neutron source

We are developing a new type of manganese bath for determination of neutron emission rate of a radioactive neutron source. The manganese bath gas a multilayered structure composed of polyethylene plates and manganese alloy plates containing 70 % manganese. In measurements of neutron emission rate, a neutron source is set in the center of the manganese bath at first. ⁵⁶Mn is produced by the ⁵⁵Mn(n,γ)⁵⁶Mn reaction. The neutron emission rate is finally determined by measuring gamma rays emitted from ⁵⁶Mn using a NaI(Tl) scintillation detector with a 5.08 cm diameter and a 5.08 cm length and a high purity Ge detector with relative efficiency of 60 %.