Exclusive e+e- and Exclusive γγ Productions

Document(s) Web Page       Public Notes: Exclusive e+e-   Exclusive γγ       Figures Contact(s) M. Albrow, B. Caron, A. Hamilton, B. Heinemann and J. Pinfold Abstract We present two exclusive production processes: exclusive e+e- production through γγ -> e+e-, and exclusive γγ production through gg -> γγ (via a quark loop). We have observed 16 exclusive e+e- production events with a background estimate of 2.1 +0.7-0.3. Each event has an e+e- pair (E_T(e) > 5 GeV, |η(e)| < 2) and nothing else observable in the CDF detector. The measured cross section is 1.6 +0.5-0.3 (stat) ± 0.3 (sys) pb, while the predicted cross section is 1.711 ± 0.008 pb. The kinematic properties of the events are consistent with the predictions of the LPAIR Monte Carlo. We have evidence for 3 exclusive γγ production events, with a background estimate of 0.0 +0.2-0.0. Each event has two photons (E_T(γ) > 5 GeV, |η(γ)| < 1) and nothing else observable in the CDF detector. The measured cross section for these events, 0.14 +0.14-0.04 (stat) ± 0.03 (sys) pb, agrees with the theoretical prediction of 0.04 pb with a factor 3 to 5 theoretical uncertainty. Comments Last Update: April 2006       Dataset: 532 pb-1