AUTOMATIC COMPENSATION OF DEAD-TIME EFFECTS

A method was proposed and demonstrated for an automatic compensation o f dead time effects, where pseudo pulses whose number are equivalent t o the counting losses due to dead time are generated as accidental coi ncidence counts by a gating method, and inserted into the observed pul se train after delay. In the present work, two gate circuits were used in order to make a 2nd order approximation to the dead time compensat ion. This method was tested for a NaI(TI) scintillation detector and a CM counter. Dead time effects were completely compensated up to 200 k s(-1) in the case of a NaI(T1) scintillation detector with a dead time of 3 mu s. Even for the case of the GM counter with an extended dead time of 250 mu s, this method is still useful up to 1 ks(-1). Since th e correction can be achieved at every instant during;counting time, th is method is applicable even when the count rate changes significantly with time. (C) 1998 Elsevier Science Ltd. All rights reserved.