DIFFERENTIAL CROSS-SECTIONS FOR GAMMA-GAMMA-]PPBAR IN THE CM ENERGY-RANGE FROM 2.0 TO 3.1 GEV

Journal article

Exclusive production of proton-antiproton pairs by two photon scattering at CM energies between 2.0 GeV and 3.1 GeV has been measured with the TASSO detector at the e+e- storage ring PETRA. The angular distribution is flat within the accepted CM angular range |cos Θ*|≤0.7. The integrated cross section (|cos Θ*|≤0.6) drops from about 4 nb at 2 GeV to less than 0.5 nb above 3 GeV. For the two-photon production of the ηc(2984) and its subsequent decay into proton-antiproton the upper limit Γ(ηc→γγ)·B(η c→pp)<0.32 keV (95% CL) is found. © 1983.

Authors: Althoff, M; Braunschweig, W; Gather, K; Kirschfink, F; Lubelsmeyer, K

• Publication status: Published
• Journal: Physics Letters B
• Volume: 130
• Issue: 6
• Pages: 449-453
• Publication date: 1983-01-01
• DOI: 10.1016/0370-2693(83)91541-1
• ISSN: 0370-2693
• Language: English