14th BEW meeting with Jadach, 26, March, 1998



Minutes taken by F. Teubert and I.Tomalin
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- Prospects for a better Monte Carlo for EW studies (S. Jadach)
  --------------------------------------------------------------




The YSF3ff Monte Carlo should be available by the Summer for all 
difermion channels, except Bhabhas which are already handled by 
BHWIDE. It will use theoretical calculations which have negligible 
error on the ISR-FSR interference. Exact calculations will be 
used for the emission of up to two photons, whilst exponentiation 
will allow an arbritary number of soft ones to be produced. This 
will however still not be the case for the Bhabhas. Furthermore, the 
error coming from W box diagrams will be unchanged at about +-0.5%. 
We can check the size of these boxes by switching them on and off in 
ZFITTER. The new Monte Carlo should be better at describing the data 
in the s'/s distribution and also in azimuthal correlations between
pairs of radiative photons (which should be small in the new MC and 
data).








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