Experimental comparison of [formula omitted] production by π±, K ±, p and p̄ beams at 39.5 GeV/ c

• Published in: Physics letters. B 1977-05, Vol.68 (1), p.96-100
• Main Authors: Corden, M.J., Dowell, J.D., Eastwood, D., Garvey, J., Homer, R.J., Jobes, M., Kenyon, I.R., McMahon, T., Vallance, R.J., Watkins, P.M., Wilson, J.A., Gago, J., Jung, M., Sonderegger, P., Treille, D., Woodworth, P.L., Eckardt, V., Fent, J., Pretzl, K., Seyboth, P., Seyerlein, J., Perrin, D., Chaurand, B., De Rosny, G., Fluri, L., Romana, A., Salmeron, R., Wijangco, A., Sumorok, K.C.T.O.
• Format: Article
• Language: English
• ISSN: 0370-2693; 1873-2445
• DOI: 10.1016/0370-2693(77)90044-2

Measurements have been made of relative production cross sections of the J ψ by π ±, K ±, p and p̄ at 39.5 GeV/ c incident on copper. J ψ production rates from π −, K − and p̄ are similar. The J ψ relative particle/anti-particle production cross sections for x>0 are σ(π +) σ(π −)=(0.87±0.14) , σ(K +)/ σ(K −)=(0.85±0.5) and σ( p) σ( p ̄ )=(0.15 ±0.08) . The small p/p̄ cross section ratio disagrees with models of J/ψ production by gluon amalgamation.