MODELING BOSE-EINSTEIN CORRELATIONS AT LEP-2

We present new algorithms for simulating Bose-Einstein correlations am ong final-state bosons in an event generator. The algorithms are all b ased on introducing Bose-Einstein correlations as a shift of final-sta te momenta among identical bosons, and differ only in the way energy a nd momentum conservation is ensured. The benefits and shortcomings of this approach, that may be viewed as a local reweighting strategy, is compared to the ones of recently proposed algorithms involving global event reweighting. We use the new algorithms to improve on our previou s study of the effects of Bose-Einstein correlations on the W mass mea surement at LEP 2. The intrinsic uncertainty could be as high as 100 M eV but is probably reduced to the order of 30 MeV with realistic exper imental reconstruction procedures.