Abstract: Background: Gadolinium-loaded liquid scintillator was widely used in the research of nuclear physics, (n,r) discrimination and distribution of neutron capture time of gadolinium-loaded liquid scintillator were main values of detecting performance. Purpose: This paper attempts to develop the 0.5%wt gadolinium-loaded liquid scintillators with better neutron gamma discrimination factor by measuring the detecting performance of gadolinium-loaded liquid scintillators of several proportion and composition. Methods: The neutron gamma discrimination of gadolinium-loaded liquid scintillator detectors were measured using zero-crossing discrimination. The distribution of neutron capture time was measured for the ?13 cm×30 cm gadolinium-loaded liquid scintillator detector with coincidence method, the start signal was got from fission fragment of 252Cf fission chamber, the stop signal was got from anode output of gadolinium-loaded liquid scintillator detector. Results: It shows that the best of neutron gamma discrimination can be offered when naphthalene is set with 7.5%wt in the gadolinium-loaded liquid scintillator. The result showed that neutron capture time of the ?13 cm×30 cm gadolinium-loaded liquid scintillator detector was distributed within 30 us, the average time of neutron capture was 11 us. Conclusion: The neutron capture time property of homemade gadolinium-loaded liquid scintillator meets the experiment requirements.

Key words: Gadolinium-loaded liquid scintillator, Distribution of neutron capture time, Fission chamber