Neutron Flux Measurements of a D-T Neutron Generator

A new D-T sealed-tube neutron generator model ING-07T (VNIIA, Russia) was installed at Soreq Nuclear Research Center. A deuterium (D) beam (a minimum 15 mm diameter) irradiates a target containing tritium (T) and via the D + T -> n+4He reaction generates neutrons at En ∼ 14.2 MeV. The neutron generator ion source is of a penning ion source type and allows continuous beam operation. The neutron production can be regulated by the acceleration voltage and ion source parameters. The specified neutron emission rate is 1*109 n/sec. Neutrons are emitted almost isotropically in space. The advantage of the sealed-tube is that it eliminates the use of a vacuum pump. The neutron generator is contained in a 44 cm long aluminum cylinder with a diameter of 19 cm. The generator is connected by a 50 m long cable to a control unit (laptop). A known method for calibration of a 14 MeV neutron flux is performed by copper activation, using the fast neutron reaction 63Cu(n,2n)62Cu, having a neutron energy threshold of En = 10.8 MeV. 62Cu decays by p+ emission (7% = 9.67 min; Pp+ = 97.43%), Photons are produced from positron-electron annihilation (511 keV) at 194.86% (2Ppt) of the disintegrations. In this paper we present a series of measurements performed in order to calibrate the neutron emission rate of the D-T generator and investigate the profile distribution of the flux