Folks, Another "new" PrimEx note: PrimEx Note 65 Photon Flux Determination for a Precision Measurement of the Neutral Pion Lifetime Aram Teymurazyan 2008 http://www/primex/primex_notes/aram_thesis.pdf Again, find the complete list of PrimEx Notes at http://www.jlab.org/primex/primex_notes/primex_notes.html -- Mark