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arXiv · 0704.3538

High statistics measurement of the cross sections of gamma gamma -> pi^+ pi^- production

T. Mori
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Abstract

We report on a high statistics measurement of the total and differential cross sections of the process gamma gamma -> pi^+ pi^- in the pi^+ pi^- invariant mass range 0.8 GeV/c^2 < W < 1.5 GeV/c^2 with 85.9 fb^{-1} of data collected at sqrt{s}=10.58 GeV and 10.52 GeV with the Belle detector. A clear signal of the f_0(980) resonance is observed in addition to the f_2(1270) resonance. An improved 90% confidence level upper limit Br.(eta'(958) -> pi^+ pi^-) < 2.9 x 10^{-3} is obtained for P- and CP-violating decay of the eta'(958) meson using the most conservative assumption about the interference with the background.

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T. Mori. 2007-04-26. High statistics measurement of the cross sections of gamma gamma -> pi^+ pi^- production. https://doi.org/10.1143/jpsj.76.074102

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