Slide 4           S.L.Olsen 4/4/96 Pictel mtg

             LOOK FOR K1(1270) IN J/psi-->k+k-pi+pi- DECAYS

INTRODUCTION
             The psi'-->k1(1270) kbar decay mode appears to be reasonably
             large, something like 0.1%.  Applying the 14% rule in reverse,
             this leads to an expectation of order 0.7% each for J/psi->k1+k-
             and J/psi->k10k0bar, which would rank them with the dominant 
             J/psi->hadrons decay channels.  However, there is no entry
             for this mode in the PDG.  

             In the absence of any J/psi data, I looked at J/psi-->k+k-pi+pi- 
             decays via the cascade decays:

                         psi'-->pi+pi- J/psi
                                         |
                                        k+k-pi+pi-

              With some simple selections on the 6prng data and a 5c fit,
              I was able to isolate a reasonably clean sample of 244 events.
              Here I note results of a first look at these data.
       
     Fig 8a:  An M_{kpipi} vs M_{kpi} scatterplot (2 entries/event). Here
              one can see some hint of a concentration of points near 
              M_{kpi}=0.89 and M_{kpipi}=1.4 GeV.    

     Fig 8b:  The k pi pi mass distribution (2 entries/event). Here there 
              is a peak near 1.4 GeV and maybe another one at 1.7 GeV.

     Fig 8c:  The pi pi mass distribution for events with M_{kpipi}<1.55.
              No strong rho signal.

     Fig 8d:  The k pi mass distribution for events with M_{kpipi}<1.55.
              A very strong k*(890) signal.

     Fig 8e:  The k*pi mass distribution.  Here a peak at 1.4 GeV is evident.

     Fig 8f:  The k "rho" mass distribution. There is some action around 
              1.4 GeV, maybe something at 1.7 GeV, but not even a hint of 
              the K1(1270). 

     Fig 9:   A fit to the k*pi mass distribution using the PDG values for
              the mass and width of the k1(1400).  A good fit and good 
              agreement with the PDG values.

PUZZLE:
            Why does he psi' decays to k1(1270 k but not k1(1400) k
            while the J/psi decays to k1(1400) k, but not k1(1270) k?