Abstract
A search for massive photon pair production at\(\sqrt s = 63 GeV\) has been carried out on the data sample previously employed for the electron pair production study. Positive evidence is reported form γγ>6GeV, with a production cross-section similar to Drell-Yan electron pairs. The ratio γγ/π0π0 was measured to be ∼10−3 for ap T of each γ or γ or π0 above 3 GeV/c.
This is a preview of subscription content, log in via an institution to check access.
Similar content being viewed by others
References
S.M. Berman et al.: Phys. Rev.D4, 3388 (1971); K. Soh et al.: Phys. Rev.D18, 751 (1978); M. Krawegky, W. Ochs: Phys. Lett.79B, 119 (1978); S. Hemmi: Prog. Theor. Phys.63, 1073 (1980)
B.L. Combridge: CALTECH preprint CALT-68-766 (1980); C. Carimalo et al.: Phys. Lett98B, 105 (1981)
F. Paige, I. Stumer: Proc. ISABELLE Summer Study, Brookhaven, 1981 (BNL-51443, p. 479. Brookhaven Nat. Lab., Upton, LI, New York, 1981)
A.P. Contogouris et al.: Two-photon production at largep T as a new test of QCD. McGill University preprint (1981)
For the calculation of the cross-section pp→γγ+X, we have used 109-1 and the distribution functions of J.F. Owens, E. Reya: Phys. Rev.D17, 303 (1978)
J.H. Cobb et al.: Phys. Lett.72B, 273 (1977); C. Kourkoumelis et al.: Phys. Lett.91B, 475 (1980)
C. Kourkoumelis et al.: Phys. Lett.84B, 271 (1979)
J.H. Cobb et al.: Phys. Rev. Lett.40, 1420 (1978); C. Kourkoumelis et al.: Phys. Lett.85B, 147 (1979); C. Kourkoumelis et al.: Nucl. Phys.B158, 39 (1979)
C. Kourkoumelis et al.: Phys. Lett.87B, 292 (1979); M. Diakonou et al.: Phys. Lett.91B, 296 (1980); E. Anassontzis et al.: Z. Phys. C — Particles and Fields13, 277 (1982)
R.L. Ford, W.R. Nelson: The EGS code system: Computer program for the Monte Carlo simulation of electromagnetic cascade showers. SLAC-210 (1978)
For ourp T range we have measured the following ratios: 109-2, 109-3, 109-4. C. Kourkoumelis et al.: Phys. Lett.84B, 277 (1979); M. Diakonou et al.: Phys. Lett.89B, 432 (1980); In the Monte Carlo program these values were assumed to be independent ofp T
M. Diakonou et al.: Phys. Lett.91B, 301 (1980); C. Kourkoumelis et al.: Nucl. Phys.B179, 1 (1981)
The ratio and the cross-sections were not corrected for the fact that real γγ events overlapping with tracks were interpreted as dileptons. We have studied the probability of chance overlap of a track with a γ within our 10° cone. We concluded that owing to our procedure, 4.7 (2.4) γγ events could have been lost forp T>3 GeV/c (4 GeV/c)
G.J. Aubrecht et al.: Ohio State University preprint COO-1545-250 (1980); R. Baier, R. Rückl: Max-Plank Inst., Munich, preprint MPI-PAE, PTH 16/82 (1982)
M. Spitzer: DESY Report 80/43 (1980).
M. Goldberg: Northeastern University preprint NUB 2425 (1980)
Author information
Authors and Affiliations
Additional information
This research was supported by the US Department of Energy, under Contract No. DE-AC02-76CH00016
Work supported by the US National Science Foundation
Rights and permissions
About this article
Cite this article
Kourkoumelis, C., Resvanis, L.K., Filippas, T.A. et al. Search for massive photon pair production at the CERN intersecting storage rings. Z. Phys. C - Particles and Fields 16, 101–109 (1982). https://doi.org/10.1007/BF01572259
Received:
Issue Date:
DOI: https://doi.org/10.1007/BF01572259