Tuesday 13 October 1998
                                               Ian Tomalin


                MINUTES OF THE 22ND BEW MEETING
               =================================

Agenda
========

  T. Medcalf     : Final Limits on Excited Leptons (Ecms <= 183).
  I. Tomalin     : New limits from indirect leptoquark search.
  M. Swynghedauw : Limit on Z'.
  C. Goy         : Systematic errors on c-cbar cross section.
  F. Teubert     : Comparison of Jadach's new MC with ZFITTER.
  I. Tomalin     : Needs for MC production.

*******************************************************************
* Sorry, nobody remembered to take the minutes. The following are *
* rather concise ...                                              *
*******************************************************************


T. Medcalf     : Final Limits on Excited Leptons (Ecms <= 183)
===============================================================
  Search made for excited electrons, muons, taus and neutrinos,
both in single and pair production. Limits obtained from pair 
production are near 91.4 GeV for charged excited leptons and 
88.0 GeV for excited neutrinos. Single production gives limits on
couplings for masses up to 183 GeV. A draft ALEPH note is available.
  Terry is considering whether to publish now, or improve analysis
further. (Looking for decays of excited leptons via W/Z aswell as
gamma; use of 189 GeV data etc.)


I. Tomalin     : New limits from indirect leptoquark search
============================================================
  Limits obtained using similar technique to contact term fit.
As a result of corrections and use of jet charge asymmtries,
the limits are now a factor of two better than those sent to 
Vancouver. However, for 1st generation LQ, are still not
competitive with limits from rare decays.

M. Swynghedauw : Limit on Z'
============================
  Uses all cross section and asymmetry measurements apart from
c-cbar, jet charge asymmetry and LEP1. Limits are in range
320-978 GeV depending on model. Only sequential SM Z0 is competitive
at present. Decision made to derive limits considering model angle  
as fixed parameter. Will perhaps in future take into account 
correlations between the data points at diffent Ecms, and use LEP1
data.

C. Goy         : Systematic errors on c-cbar cross section
===========================================================
  Alternative assessment of systematic errors on c-cbar cross section
analysis presented. Using analysis at Z0 peak gives 
sigma_cc(data) = 5.57 +- 0.05 pb, (ZFITTER) = 5.16 pb.
Attempt at measuring systematics in tagging efficiencies directly at 
LEP2 by trying tag on pure samples of uds, c and b events. Works
OK for yds and b events, but for c events, not possible to get
very pure sample. Analysis implies similar systematic errors to older
method however.

I. Tomalin     : Needs for MC production
=========================================
  At 189 GeV, need several times more MC than data. At present,
most urgent requirements are:
   gg -> qq    = (NONE available)
   KORL08 (qq) = (only 400 pb**-1 available)

Difermion MC generated at Z0 peak with 98 geometry would also be useful.
It would also be desirable to use GAL307 when available, and 
to find a volunteer to test and implement Jadach's new qq Monte Carlo,
which is better than KORL08.

A.O.B.
======
  Marie-Noelle mentioned that Elsa's Bhabha cross section at 189 GeV
is much too low, and depends strongly on phi ! This is possibly due
to systematic bias in the measurements of track momenta. It was
suggested that this be discussed at the next meeting in preparation
for the LEPC.