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Hello folks, I have been investigating the problem reported by Daniele in http://www.slac.stanford.edu/cgi-bin/lwgate/VUB-RECOIL/archives/vub-recoil.200211/Author/article-35.html i.e. that there was a significant change in the result (and therefore in the mxhad agreement) between different photon selections. I have been checking the mean value of the number of neutrals (nneu) for events with p*>1 and in the depleted sample, in order to understand which cuts had the biggest impact on the sample of neutrals. Hera re the results: selection <nneu> egamma> 50 MeV 4.75 ------------------- egamma> 50 MeV 3.99 acceptance (theta>0.41) ------------------- egamma + acc 3.93 S9S25>0.9 ------------------- egamma+acc+S9S25 3.39 lat>0.05&&lat<0.5 It looks like the biggest impact comes from the acceptance, which should remove only 10% if it were space phace, but it removes much more. I have therefore tried out trk7 gam7 (i.e. all cuts including the unmatched clusters removal) having removed the acceptance cut and called it trk7 gam8. The comparison plots are in http://www.slac.stanford.edu/~rfaccini/phys/vub/comp_110602B0-trk7gam8/-comp.html and http://www.slac.stanford.edu/~rfaccini/phys/vub/comp_110602Bch-trk7gam8/-comp.html there is no striking improvement ciao ric