Asymmetries in the Production of Lambda0 in 250 GeV/c pi+-, K+- and p -- Nucleon Interactions

G. A. Alves, S. Amato, J. C. Anjos, J. A. Appel, J. Astorga, T. Bernard, S. B. Bracker, L. M. Cremaldi, W. D. Dagenhart, C. L. Darling, D. Errede, H. C. Fenker, C. Gay, D. R. Green, R. Jedicke, P. E. Karchin, S. Kwan, L. H. Lueking, J. R. T. de Mello Neto, J. Metheny, R. H. Milburn, J. M. de Miranda, H. da Motta, A. Napier, M. S. Nicola, D. Passmore, A. Rafatian, A. C. dos Reis, W. R. Ross, A. F. S. Santoro, M. Sheaff, M. H. G. Souza, C. Stoughton, M. E. Streetman, D. J. Summers, S. F. Takach, A. Wallace, Z. Wu

Published 2003-03-19Version 1

Using data from Fermilab fixed-target experiment E769, we have measured particle-antiparticle production asymmetries for Lambda0 hyperons in 250 GeV/c pi+-, K+- and p -- nucleon interactions. The asymmetries are measured as functions of Feynman-x (x_F) and p_t^2 over the ranges -0.12<=x_F<=0.12 and 0<=p_t^2<=3 (GeV/c)^2 (for positive beam) and -0.12<=x_F<=0.4 and 0<=p_t^2<=10 (GeV/c)^2 (for negative beam). We find substantial asymmetries, even at x_F around zero. We also observe leading-particle-type asymmetries. These latter effects are qualitatively as expected from valence-quark content of the target and variety of projectiles studied.