Measurement of the production of high-massγ γ, π0 π0, and γ π0 pairs in π-p, π+p, and pp collisions at 300 GeV/c

de Marzo, C.; de Palma, M.; Favuzzi, C.; Maggi, G.; Nappi, E.; Posa, F.; Ranieri, A.; Selvaggi, G.; Spinelli, P.; Bamberger, A.; Fuchs, M.; Heck, W.; Loos, C.; Marx, R.; Runge, K.; Skodzek, E.; Weber, C.; Wülker, M.; Zetsche, F.; Artemiev, V.; Galaktionov, Yu.; Gordeev, A.; Gorodkov, Yu.; Kamyshkov, Yu.; Plyaskin, V.; Pojidaev, V.; Shevchenko, V.; Shumilov, E.; Tchudakov, V.; Bunn, J.; Fent, J.; Freund, P.; Gebauer, J.; Glas, M.; Polakos, P.; Pretzl, K.; Schouten, T.; Seyboth, P.; Seyerlein, J.; Vesztergombi, G.

doi:10.1103/PhysRevD.42.748

The NA24 experiment at CERN investigated inclusive γγ, π0π0, and γπ0 final states in the mass range between 4 and 9 GeV/c2 produced in π−p, π+p, and pp reactions at a c.m.-system energy √s=23.7 GeV. The π0π0 cross sections agree well with expectations of the quark-parton model. For γπ0 production in π−p and pp reactions, a clear signal is observed and cross sections are shown. The production of γγ events was observed with a statistical significance of 2.9σ in π−p reactions. The cross section is in agreement with a higher-order QCD prediction.

Measurement of the production of high-massγ γ, π0 π0, and γ π0 pairs in π-p, π+p, and pp collisions at 300 GeV/c / de Marzo, C.; de Palma, M.; Favuzzi, C.; Maggi, G.; Nappi, E.; Posa, F.; Ranieri, A.; Selvaggi, G.; Spinelli, P.; Bamberger, A.; Fuchs, M.; Heck, W.; Loos, C.; Marx, R.; Runge, K.; Skodzek, E.; Weber, C.; Wülker, M.; Zetsche, F.; Artemiev, V.; Galaktionov, Yu.; Gordeev, A.; Gorodkov, Yu.; Kamyshkov, Yu.; Plyaskin, V.; Pojidaev, V.; Shevchenko, V.; Shumilov, E.; Tchudakov, V.; Bunn, J.; Fent, J.; Freund, P.; Gebauer, J.; Glas, M.; Polakos, P.; Pretzl, K.; Schouten, T.; Seyboth, P.; Seyerlein, J.; Vesztergombi, G.. - In: PHYSICAL REVIEW D. - ISSN 0556-2821. - STAMPA. - 42:3(1990), pp. 748-758. [10.1103/PhysRevD.42.748]