Abstract
We have searched for exclusive production in proton-antiproton collisions at , using of integrated luminosity taken by the run II Collider Detector at Fermilab. The event signature requires two electromagnetic showers, each with transverse energy and pseudorapidity , with no other particles detected in the event. Three candidate events are observed. We discuss the consistency of the three events with , , or production. The probability that other processes fluctuate to events is . An upper limit on the cross section of production is set at 410 fb with 95% confidence level.
- Received 18 July 2007
DOI:https://doi.org/10.1103/PhysRevLett.99.242002
©2007 American Physical Society