The TCAR Bank

• Has the same format as an NTPR, but, unlike the NTPR, only one can be active at a time. TCARs can be disabled and enabled with e.g.:-
  • $tca_disable_ntuple 500
  • $tca_enable_ntuple 600

• The parameters of the DQF must only be:-
  • Literals e.g. 3.0

  • The name of an input variable with the suff1x _1 (primary) or _2 (secondary) e.g. time_1. TCA creates an extra input variable ENTRY_NO that gives the position of the event in the input file. This too can be accessed e.g. ENTRY_NO_2.

  • The name of a preceeding variable in the output n-tuple e.g. del_time as in:-

    del_time     ntime_difference  time_jdy_1,time_jdy_2;
    _sort_on     abs               del_time;
    

• The variable name _sort_on is special. If present and if a primary forms more than one association, TCA will sort on this variable. Use this variable as a type of association chi-squared - the smaller the better.

• The DQF TCA_AMBIGUITY generates the undefined value.:-

  ambig        tca_ambiguity     ;
  order        reserved          ;
  

  Only when TCA is about to output the event is the correct value inserted:-
  • ambig - the number of times the event formed an association as a primary. For unassociated primaries, this will be zero.

  • order - the position in the sorted list of this association, with 1 meaning the first entry i.e. best.
  Do not place cuts on these variables or use them as input parameters in later entries in the n-tuple: you will just be dealing with the undefined value!

• If the input n-tuple contains the ``undefined'' value, this value must also be used in the output n-tuple. The recommended value is -999999.