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DeadT - Dead time calculator

Overview

This program is used to solve the deadtime of a data acquisition system.

If there are NTrig triggers coming in TSpill sec, and each trigger consumes DeadT sec, then only NEvt events will be read out. The Solver is used to solve the following relationship.

         NEvt         NEvt * DeadT                                              
        ------ = 1 - --------------                                             
         NTrig           TSpill                                                 
			

Variables

TSpill : spill length in sec
DeadT : deadtime per accepted event in sec
NTrig : the number of incoming triggers per spill
NEvt : the number of accepted events per spill

Stack/Registers/Flags

x, y, z and t stack registers are used and destroyed.
No registers are used.
No flags are used.

Example

Assume that there are 400k in-coming triggers in 20sec, and the deadtime is 100 microsec per accepted event. Find the number of accepted events per spill.

	SOLVER
	"DEADT"
	20    TSpill
	100E-5 DeadT
	400E3 NTrig
	NEvt
	    returns ...
	    NEvt=1.33E5  (only 1/3 of triggers are accepted)
			

In the above case, if we want to read out 300k events per spill, what is the required deadtime per event?

	SOLVER
	"DEADT"
	20    TSpill
	400E3 NTrig
	300E3 NEvt
	DeadT
        returns ...
        DeadT=1.675E-5 (17 microsec)
			

Program

V1.00 May 20, 1991

    00   { 70-Byte Prgm }              ;                                        
    01   LBL "DEADT"                   ;                                        
    02   MVAR "TSpill"                 ;                                        
    03   MVAR "DeadT"                  ;                                        
    04   MVAR "NTrig"                  ;                                        
    05   MVAR "NEvt"                   ;                                        
    06   RCL  "NEvt"                   ;                                        
    07   RCL/ "NTrig"                  ;                                        
    08   LASTX                         ;                                        
    09   RCLx "DeadT"                  ;                                        
    10   RCL/ "TSpill"                 ;                                        
    11   +                             ;                                        
    12   1                             ;                                        
    13   -                             ;                                        
    14   END                           ;                                       
			

Programmed by Taku Yamanaka, May 20, 1991