10,000 Sets of Neutron Time-of-Flight (ToF) Signals from a Photoneutron Source Driven by an 8 ps Pulsed 45 MeV Electron Beam

The experiment was performed at the accelerator laboratory of Tsinghua University, where an ultra-short pulsed electron linear accelerator (e-LINAC) was utilized to generate electron beam pulses. These pulses were directed at a tantalum (Ta) target (φ20 mm × 16 mm cylinder) positioned approximately 2 cm in front of the e-LINAC Ti window.

The interaction between the electron beam and the Ta-target facilitated the conversion of electrons to neutrons via the e→γ→n process, producing a continuous neutron energy spectrum ranging from sub-keV levels to over 10 MeV. The neutron-beam intensity reached up to 1.925 × 10^8 n/s, with an electron intensity of 0.7 nC/pulse at a repetition rate of 10 Hz.The ToF measurements were conducted over a distance of 5 meters using a neutron detection system comprising a φ100 mm × 100 mm EJ299-33A plastic scintillator coupled with a Hamamatsu R13089 photomultiplier tube (PMT).