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arXiv · hep-ex/9601001

Asymmetries between the production of D+ and D- mesons from 500 GeV/c pi- nucleon interactions as a function of xF and pt**2

E. M. Aitala·S. Amato·J. C. Anjos·J. A. Appel·M. Aryal·D. Ashery·J. Astorga·S. Banerjee·I. Bediaga·G. Blaylock·S. B. Bracker·P. R. Burchat·R. A. Burnstein·T. Carter·H. S. Carvalho·I. Costa·L. M. Cremaldi·C. Darling·K. Denisenko·A. Fernandez·P. Gagnon·S. Gerzon·C. Gobel·K. Gounder·D. Granite·A. M. Halling·G. Herrera·G. Hurvits·C. James·P. A. Kasper·N. Kondakis·S. Kwan·D. C. Langs·J. Leslie·J. Lichtenstadt·B. Lundberg·A. Manacero·S. MayTal-Beck·B. Meadows·J. R. T. de Mello Neto·R. H. Milburn·J. M. de Miranda·A. Napier·A. Nguyen·A. B. d'Oliveira·K. O'Shaughnessy·K. C. Peng·L. P. Perera·M. V. Purohit·B. Quinn·S. Radeztsky·A. Rafatian·N. W. Reay·J. J. Reidy·A. C. Reis·H. A. Rubin·A. K. S. Santha·A. F. S. Santoro·A. J. Schwartz·M. Sheaff·R. A. Sidwell·A. J. Slaughter·J. G. Smith·M. D. Sokoloff·N. R. Stanton·K. Sugano·D. J. Summers·S. Takach·K. Thorne·A. K. Tripathi·S. Watanabe·R. Weiss-Babai·J. Wiener·N. Witchey·E. Wolin·D. Yi·R. Zaliznyak·C. Zhang
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Abstract

We present asymmetries between the production of D+ and D- mesons in Fermilab experiment E791 as a function of xF and pt**2. The data used here consist of 74,000 fully-reconstructed charmed mesons produced by a 500 GeV/c pi- beam on C and Pt foils. The measurements are compared to results of models which predict differences between the production of heavy-quark mesons that have a light quark in common with the beam (leading particles) and those that do not (non-leading particles). While the default models do not agree with our data, we can reach agreement with one of them, PYTHIA, by making a limited number of changes to parameters used.

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E. M. Aitala, S. Amato, J. C. Anjos, J. A. Appel, M. Aryal, D. Ashery, J. Astorga, S. Banerjee, I. Bediaga, G. Blaylock, S. B. Bracker, P. R. Burchat, R. A. Burnstein, T. Carter, H. S. Carvalho, I. Costa, L. M. Cremaldi, C. Darling, K. Denisenko, A. Fernandez, P. Gagnon, S. Gerzon, C. Gobel, K. Gounder, D. Granite, A. M. Halling, G. Herrera, G. Hurvits, C. James, P. A. Kasper, N. Kondakis, S. Kwan, D. C. Langs, J. Leslie, J. Lichtenstadt, B. Lundberg, A. Manacero, S. MayTal-Beck, B. Meadows, J. R. T. de Mello Neto, R. H. Milburn, J. M. de Miranda, A. Napier, A. Nguyen, A. B. d'Oliveira, K. O'Shaughnessy, K. C. Peng, L. P. Perera, M. V. Purohit, B. Quinn, S. Radeztsky, A. Rafatian, N. W. Reay, J. J. Reidy, A. C. Reis, H. A. Rubin, A. K. S. Santha, A. F. S. Santoro, A. J. Schwartz, M. Sheaff, R. A. Sidwell, A. J. Slaughter, J. G. Smith, M. D. Sokoloff, N. R. Stanton, K. Sugano, D. J. Summers, S. Takach, K. Thorne, A. K. Tripathi, S. Watanabe, R. Weiss-Babai, J. Wiener, N. Witchey, E. Wolin, D. Yi, R. Zaliznyak, C. Zhang. 1996-01-04. Asymmetries between the production of D+ and D- mesons from 500 GeV/c pi- nucleon interactions as a function of xF and pt**2. https://doi.org/10.1016/0370-2693(96)00093-7

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