The detector for AGS Experiment 787 at Brookhaven National Laboratory
has been built to begin the search to observe the decay 
if it occurs
at the level predicted by the Standard Model. New limits for 
,
, 
, and 
decays
have been reported from the analysis of the
first data run which corresponds to 
stopped 
s. Subsequent data corresponding to an order of magnitude
more statistical sensitivity have been obtained and analysis
is in progress. Several improvements to the detector and beamline
are under way or
under study to ensure that the full sensitivity required to
test the Standard Model predictions will be achieved.
This project was carried out thanks to the talented contributions of the following people and we are pleased to acknowledge them here: G. Azuelos, D.G. Bartolomeo, P. Bichoneau, J.C. Biggs, C. Bopp, D.R. Brady, S. Chidzik, M. Constable, H. Coombes, J. Cracco, J.R. Cuccia, S. Daviel, W. Groom, R. Henderson, W.E. Lenz, C. Lim, S. Moreale, G.J. Munoz, R. Openshaw, R. Rabberman, H. Ratzke, W. Sands, H.W. Sauter, R.J. Strzelinski, and M.R. Van Lith.
We thank D.I. Lowenstein for use of the steel for the detector magnet. We appreciate the help from W.J. McGahern and the AGS Experimental Areas Group, and from R.J. Spellman and the BNL Central Shop staff.
We wish also to acknowledge the funding support of this project by the National Research Council of Canada, the Natural Sciences and Engineering Research Council of Canada, and the United States Department of Energy under Contracts No.DE-AC02-76CH00016, No.W-7405-ENG-36 and No.DE-AC02-76ER03072.