| In the Extensive Air Shower,hadrons contain a large amount of information about the primary particles.These hadrons interact with target materials,such as soil and sand,and then will produce large numbers of thermal neutrons.Recording these thermal neutrons,cosmic ray studies can be carried out.The thermal neutron detectors,a type of novel EAS detectors,can simultaneously measure charged particles and thermal neutrons in the EAS,and can study the EAS from the perspective of thermal neutrons.In order to examine the performance of those detectors and their array,and to analyze the influence of environmental factors such as target material on the detection performance.Researches mentioned above are carried out utilizing the PRISMA-16-YBJ thermal neutron detector array at the Yangbajing Cosmic Ray Observatory.After adjusting the neutron gain of detectors according to the single neutron pulse height distribution for relative calibration,we investigate the influence of the noise baseline algorithm,atmospheric parameters,and target material composition on the performance of the PRISMA-16-YBJ array.After optimizing the noise baseline algorithm,the neutron detection threshold energy of the detector had been decreased,and the number of events recorded by the array was increased,solving the problem of low number of neutrons in the past.On the other hand,in the long-term performance monitoring of the array,it was found that the triggered events rate increase with the decreases of temperature,while the change of air pressure does not have a significant effect on the rate.Finally,performance studies based on “Sand Cubes” show that the difference in the composition of the two target materials,soil and gravel,does not significantly affect the neutron detection performance of the detector.However,the “Sand Cubes” reduces the target material around the detector,which weakens the neutron moderation of array and ultimately leads to a reduction in the number of triggered events recorded by the array. |
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