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TCQUENCH

sets time cutoffs and/or quenching factors when scoring using the USRBIN or the EVENTBIN options.

See also TIME-CUT

     WHAT(1) > 0.0 : time cutoff for scoring (seconds)
             < 0.0 : resets any previously requested time cutoff to
                     default (infinity)
             = 0.0 : ignored

     WHAT(2) > 0.0 : first Birks law coefficient in g/(MeV cm2)
             = 0.0 : ignored
             < 0.0 : resets both Birks law coefficients to default = 0.0

     WHAT(3) > 0.0 : second Birks law coefficient in g2/(MeV2 cm4)
               Default = 0.0

     WHAT(4) = lower index bound of binnings in which the requested
               scoring time cutoff and/or Birks law coefficients must be
               applied ("From binning WHAT(4)...")
               Default = 1.0

     WHAT(5) = upper index bound of binnings in which the requested
               scoring time cutoff and/or Birks law coefficients must be
               applied ("...To  binning WHAT(5)..."
               Default = WHAT(4)

     WHAT(6) = step length in assigning indices ("...in steps of
               WHAT(6)").
               Default = 1.0

     SDUM :    not used

     Default (option TCQUENCH not given): no time cutoff for scoring and
               no quenching of dose binning

Notes:

• 1) Binnings are numbered sequentially in the order they are input via the USRBIN or EVENTBIN options. Of course, for quenching to be applied the quantity binned must be energy (generalised particle 208 or 211). The energy deposited in a charged particle step is "quenched" according to Birks law, i.e. it is weighted with a factor dependent on stopping power S = dE/dx:

                      dE' = dE/(1 + BS + CS**2)

with B = first Birks parameter and C = Chou or second Birks parameter [Bir64].

• 2) The time cutoff is useful in order to score only within a time gate between t = 0 and t = cutoff

• 3) The scoring time cutoff should not be confused with the time cutoff for transport (see TIME-CUT). Particles outside the time gate defined by TCQUENCH are still transported and can contribute to scoring in regions and in binnings having a different time scoring cutoff.

Example:

 *...+....1....+....2....+....3....+....4....+....5....+....6....+....7....+....8
 TCQUENCH        20.0   7.35E-3   1.45E-5       4.0      10.0       3.0
 *  Set a 20 sec time scoring cutoff for binnings 4, 7 and 10, and apply to
 *  them the NE213 scintillator Birks parameters published by Craun and
 *  Smith, Nucl. Instr. Meth. 80, 239 (1970)