Thrust

Input argument:

ICLASS

described in 10.3.

Results:

THRUST

Thrust value.

'thrust-axis'

Thrust axis.

Error conditions:

No track

THRUST value 0.; output vector = 0.,0.,0.,0.

One track

thrust value = 1; output vector = track vector.

When reading MINIs ( versions $\geq$ 10 ) :

The thrust calculation is very CPU-time consuming. To save time when reading a MINI, from MINI 10 onwards (written since December 1994) the thrust axis and value are calculated using the 'EF' option in QJOPTR (see 10.1.1). The results are stored in a special bank on the MINI. When reading these MINIs, the thrust axis and value are not computed from scratch, but read directly from this bank.

You don't need to change anything to your program if you want to use the 'EF' option. If you want to compute the thrust with another option, you MUST give the following sequence of calls:

      XJTHRU=.TRUE.
      CALL QJOPTR ('your reco-option' , 'additional' )
      CALL QJTHRU(THRUST,'thrust-axis',ICLASS)

The logical variable XJTHRU belongs to the QCDE include file of ALPHA, and is set to .FALSE. at the beginning of each event.