Please use this identifier to cite or link to this item:
Title: Observation of Exclusive γγ Production in pp̅ Collisions at √s=1.96  TeV
Authors: Aaltonen, T., Álvarez González, B., Casal, Bruno, Gómez, G., Palencia, Enrique, Rodrigo, Teresa, Scodellaro, Luca, Vila, Iván, Vilar, Rocío, Vizán, J., CDF Collaboration
Issue Date: 2012
Publisher: American Physical Society
Abstract: We have observed exclusive γγ production in proton-antiproton collisions at √s=1.96  TeV, using data from 1.11±0.07  fb-1 integrated luminosity taken by the Run II Collider Detector at Fermilab. We selected events with two electromagnetic showers, each with transverse energy ET>2.5  GeV and pseudorapidity |η|<1.0, with no other particles detected in -7.4<η<+7.4. The two showers have similar ET and azimuthal angle separation Δϕ∼π; 34 events have two charged particle tracks, consistent with the QED process pp̅ →p+e+e-+p̅ by two-photon exchange, while 43 events have no charged tracks. The number of these events that are exclusive π0π0 is consistent with zero and is <15 at 95% C.L. The cross section for pp̅ →p+γγ+p̅ with |η(γ)|<1.0 and ET(γ)>2.5  GeV is 2.48-0.35+0.40(stat)-0.51+0.40(syst)  pb.
Publisher version (URL):
Identifiers: doi: 10.1103/PhysRevLett.108.081801
issn: 0031-9007
e-issn: 1079-7114
Citation: Physical Review Letters 108(8): 081801 (2012)
Appears in Collections:(IFCA) Artículos
Files in This Item:
File Description SizeFormat 
Observation of Exclusive.pdf377,47 kBAdobe PDFView/Open
Show full item record

Items in Digital.CSIC are protected by copyright, with all rights reserved, unless otherwise indicated.