The Simulation Of Discriminating Radon Isotopes By Delayed Coincidence

Radium isotopes study have an wide application in the field of oceanography, for example, study on the oceanography process of estuarine area and nearshore within 1-10 days etc. we can indirectly measure radium isotopes by logic delayed circuit which can directly measure and discriminate radon isotopes, and this method is an important means of measure radium isotopes in oceanography. In this paper we seek to generate pseudo nuclear pulse data of radon and radon isotopes by the way of software. and using MATLAB software simulate the delay coincidence to study"Ra.De.CC", This method can conveniently change the delay time and the gate time for finding a better effect . simulation the delay and gate parameters with different particles numbers and AR activity ratio. Finding that, the appropriate gate time is 3-5 times of the half-life of radon daughters, and checking with foreign measuring results in literature, the result shows that this method can reduce the cost of measurement, easily change, is a reference for measuring low level radon isotope.At the same time ,we have a study on the digital delay coincidence, for example the ADC sampling rate and sampling bit for the double exponential nuclear pulse signal. simulate four types bandpass filter, and through the research we found that the effect of elliptic filter for high-frequency noise is better for digital double exponential nuclear pulse signal.