Cross sections and some features of charm photoproduction at γ energies of 20–70 GeV

doi:10.1016/0370-2693(87)91125-7

Physics Letters B

Volume 187, Issues 3–4, 26 March 1987, Pages 437-441

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Abstract

We report some results on charm photoproduction at γ energies ranging from 20 to 70 GeV. 36 events with pairs of charmed particles have been found in emulsions. The computed total cross section is (230±57)nb/nucleon. Frequencies of different production channels and some distributions are presented and compared with the predictions from a photon-gluon fusion model with string fragmentation.

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^☆: The authors wish to dedicate this work to the memory of their deceased friends and colleagues Giuliano di Caporiacco and Tsai Chu.

¹: Deceased.

^∗: We acknowledge the essential contributions of the Omega-Photon Collaboration, the Omega technical staff and the DD Division. We express our thanks to the team of the late Dr. C. Lubomilov at Dubna as well as to Mrs. M. Galand and Mr. O. Mendola at CERN for the processing of the emulsions. Our gratitude is also due to the scanning teams for their perseverance and efficiency.

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Cross sections and some features of charm photoproduction at γ energies of 20–70 GeV☆

Abstract

Nucl. Phys. B

Phys. Lett. B

Phys. Rev. Lett.

Nuovo Cimento

Review of Particle Properties

Rev. Mod. Phys.