MC Crosstalk Generation

                              Titles:  MCXT
                              =============
 
Contact:  N. West, Oxford.
 
 
Revision History:-
================
 
3.02    N. West         First version.


 
Titles Files
------------
 
mc_crosstalk.dat
 
 
Verification
------------
 
 
Description
-----------

    This bank controls the generation of crosstalk in the Monte Carlo as follows:-

    1)   Look for MCPMs with charge above _THRESH.
    2)   For each:-
         1)   Use Xtalk Mean Width Model to compute a width.
         2)   Use Xtalk RMS Width Model to compute an RMS of the width.
         3)   Pick a width randomly usung mean and RMS.
         4)   Use Channel Position Look-up Table to determine which channels are within
              width and for each:-
              1)   Use Xtalk Charge Model to select a charge and create an MCPM.

Data Words
----------
 
       I = integer, F = floating point
 
                   Fixed length Database Header. See titles_dbhdr
 
         KMCXT...  Mnemonic relative to start of user data e.g.
                   icons(ldgeds + KGEDS_THRESH) is the threshold.
 

   1  F _THRESH      Charge threshold to generate xtalk.  Set <=0. to disable.
2..10 F              Spare

     Channel Position Look-up Table

     Xtalk affects all channels within a pulse height dependent distance of
     a high signal channel.  This table relates channel number to distance
     in units in which neighbouring channels on the same daughter board (DB) 
     are 1.0 unit apart.  The table accounts for the fact that the distance 
     between neighbouring channels on different DBs is greater than 1.0

  11  F _CHAN_POS    Position of channel 0
  12  F              Position of channel 1
...
  42  F              Position of channel 32


     Xtalk Mean Width Model

     This model translates a given charge above threshold into a mean width.

  43  F _WMEAN_MODEL Parameterisation type. See below. Must be 1.0. 
  44  F _WMEAN_P1    Parameter 1.
  45  F _WMEAN_P2    Parameter 2.
  46  F _WMEAN_P3    Parameter 3.
 ..           

     Xtalk Width RMS Model

     This model translates a given charge above threshold into a width RMS.

  54  F _WRMS_MODEL Parameterisation type. See below. Must be 1.0.  
  55  F _WRMS_P1    Parameter 1. 
  56  F _WRMS_P2    Parameter 2. 
  57  F _WRMS_P3    Parameter 3.
...

     Xtalk Charge Model

     This model translates a given charge above threshold into induced charge
     on neighbouring channel.

 
  65  F _CHARGE_MODEL Parameterisation type. See below. Must be 0.
  66  F _CHARGE_P1   Parameter 1.
  67  F _CHARGE_P2   Parameter 2.
  68  F _CHARGE_P3   Parameter 3.


     Xtalk models

     Currently the Xtalk generation models are hardwired, although the
     bank has been designed so that alternative models could be implimented.

     Model      Parameterisation (Pi = parameter i)

      0.        P1
      1.        P1  +  P2 * exp ( Qhs / P3 )