J/t) Results from Mark Iii+

Measurements of the two-body decays of the J/$ into vector and pseudoscalar meson pairs are presented. Using the measured branching ratios, a phenomenological model of J/G d eta y s indicates that the 7 and 7’ are composed only of light and strange quarks, without a gluonium contribution in the $ wavefunction. A measurement of J/+ -+ yr+rrr-n+ris presented. The fr (1285) is observed and its spin and parity are investigated. The qc is observed to decay to pope, and first indications of qc decays to f2j’z are presented. The spin and parity of the qe are investigated. Presented at the VIIIth International Workshop on Photon Photon Collisions, Jerusalem, Israel, April 24-28, 1988 t Work supported by the Department of Energy contract DEAC03-76SF00515 and by the National Science Foundation. $ Caltech: D. Coffman, G.P. Dubois, G. Eigen, J. Hauser, D.G. Hitlin, C.G. Matthews, A. Mincer, J.D. Richman, W.J. Wisniewski, Y. Zhu; Santa Cruz: M. Burchell, D.E. Dorfan, J. Drinkard, C. Gatto, R.P. Hamilton, C.A. Heusch, L. Kijpke, W.S. Lockman, R. Partridge, H.F.W. Sadrozinski, M. Scarlatella, T.L. Schalk, A. Seiden, A.J. Weinstein, S. Weseler, R. Xu; Illinois: J. J. Becker, G.T. Blaylock, B.I. Eisenstein, T. Freese, G. Gladding, J. M. Izen, S.A. Plaetzer, C. Simopoulos, A.L. Spadafora, I.E. Stockdale, B. Tripsas; Iowa: U. Mallik; SLAC: J. Adler, T. Bolton, J. C. Brient, K.O. Bunnell, R.E. Cassell, D.H. Coward, K.F. Einsweiler, C. Grab, U. Mallik, R.F. Mozley, A. Odian, D. Pitman, R.H. Schindler, W. Stockhausen, W. Toki, F. Villa, S. Wasserbaech, N. Wermes, D. Wisinski; Washington: J.S. Brown, T.H. Burnett, V. Cook, A.L. Duncan, A. Li, R. Mir, P.M. Mockett, B. Nemati, L. Parrish, H. J. Willutzki. J/G Decays to Vector Pseudoscalar Meson Pairs.[‘l The J/$(3097) is the lowest lying cz vector meson. The narrow width (63 keV) of the J/$ is a consequence of disconnected quark lines in its decay (OZI rule). A full set of measurements of J/$J -+ VP decays enables us to study the contributions of the different processes to the decay rates, the mixing angle in the pseudoscalar meson nonet, and the quark content of the 7 and 7’ mesons. Our data, taken with the Mark III detector at the SLAC e+estorage ring SPEAR, consist of 5.8 x lo6 produced J/ll, ‘s. All J/~/J + VP decays are analyzed. Most processes are observed in more than one decay mode of the pseudoscalar, thus enabling us to cross-check our measurements. Our results are summarized in Table I, where the first error is statistical and the second systematic. Table I. J/q -+ VP branching ratios. J/$ + Branching ratio (10m3) J/$ + Branching ratio (10m3) K*+K+ c.c . 5.26 f 0.13 310.53 wr” 0.482 rt 0.019 f 0.064 K*Ol?O + C.C. 4.33 rf 0.12 f 0.45 WV 1.71 f 0.08 f 0.20 P-/r 14.2 f 0.1 f 1.9 (0’ 0.166 f 0.017 f 0.019 Prl 0.193 f 0.013 xk 0.029 qw <0.0068 (90% CL) PI 0.114 f 0.014 f 0.016 &j 0.661 f 0.045 f 0.078 47’ 0.308 f 0.034 f 0.036 The widths of J/ll, into the VP meson pairs are equal to 1 Ail2 x pci, where pvi is the momentum of the vector meson in the rest frame of the J/$. In a recent phenomenological mode1’21 the amplitudes Ai are composed of strong, SU(3) violating and electromagnetic processes as well as processes with more than one disconnected quark line (DOZI processes). The 7 and 7’ mesons can be parametrized by: 14 = Xr& Iuii+ CL?) + Yv IS), Iq’) = Xv’-& IuE+ d;i) + Yvj 1~3). We fit the phenomenological model to the ten reduced branching ratios with the constraints Xf + Yi2 = 1 and X,J = -Yq. The fit yields Yq = -0.581 from which we calculate the mixing angle in the pseudoscalar nonet to be: 19~ = (-19.2 f 1.4)O. The result for 8, is in good agreement with recent two-photon results.131 A fit to the data, without the above constraints on Xi and Yi yields Xi + Yl = 1.00 f 0.16 and X;I”, + Y$ = 1.44 f. 0.26. The results of the unconstrained fit indicate that the model where the Q and 7’ consist of only u, d and s quarks, with no contribution from gluonium, is consistent with the data. J/T/I Decays to yr+rr-7r+7rThe radiative decay J/$ -+ yrr+rr-r+rh as b een studied previously by Mark III, with a smaller data sample.[41 The present analysis is still in progress, and is therefore preliminary. Our data, taken with the Mark III detector at the