Abstract
A search for events with photon pairs of large invariant mass is described based on a data sample of 43 pb-1 collected with the OPAL detector. This search is motivated by the L3 observation of four events of the type e+e- → l+l-γγ with an invariant mass of the two photons, mγγ, clustering around 60 GeV. In the OPAL data, four ℓ+ℓ-γγ events are found with mγγ above 40 GeV. The number of observed events is consistent with the QED expectation and no obvious resonance structure is seen. Three candidate qq̄γγ events with mγγ above 40 GeV are found and no νν̄nγγ candidate with mγγ > 5 GeV is found. From these searches an upper limit is set on any anomalous production of ℓ+ℓ-γγ (ℓ = e, μ, τ) events, where the ℓ+ℓ- pair comes from a virtual Z0 and mγγ is near 60 GeV, of B(Z0 → Z*0γγ → ℓ+ℓ-γγ) < 6.0 × 10-7 at the 95% CL. In a similar search in the reaction e+e- → γγγ, seven events are observed with a photon pairing of mass near 60 GeV compared to an expected background of 2.7 ± 0.4 from QED. In a search for the production of a 60 GeV resonance X in two-photon collisions, an upper limit is set on ΓXB2(X → γγ) of 2.6 MeV at the 95% CL. A search is also performed for ℓ+ℓ-X (ℓ = e, μ) events in non-γγ decay modes of X. No indication of a 60 GeV resonance is seen. Combining these two searches, ΓX values greater than 110 MeV are excluded at the 95% CL for ℓ+ℓ-γγ (ℓ = e, μ) cross-sections greater than 0.05 pb.
| Original language | English |
|---|---|
| Pages (from-to) | 391-407 |
| Number of pages | 17 |
| Journal | Physics Letters B |
| Volume | 311 |
| Issue number | 1-4 |
| DOIs | |
| Publication status | Published - 1993 Jul 29 |
| Externally published | Yes |
ASJC Scopus subject areas
- Nuclear and High Energy Physics
Access to Document
Other files and links
Fingerprint
Dive into the research topics of 'Search for anomalous production of high mass photon pairs in e+e- collisions at LEP'. Together they form a unique fingerprint.Cite this
- APA
- Standard
- Harvard
- Vancouver
- Author
- BIBTEX
- RIS
In: Physics Letters B, Vol. 311, No. 1-4, 29.07.1993, p. 391-407.
Research output: Contribution to journal › Article › peer-review
}
TY - JOUR
T1 - Search for anomalous production of high mass photon pairs in e+e- collisions at LEP
AU - Acton, P. D.
AU - Akers, R.
AU - Alexander, G.
AU - Allison, J.
AU - Anderson, K. J.
AU - Arcelli, S.
AU - Astbury, A.
AU - Axen, D.
AU - Azuelos, G.
AU - Baines, J. T.M.
AU - Ball, A. H.
AU - Banks, J.
AU - Barlow, R. J.
AU - Barnett, S.
AU - Bartoldus, R.
AU - Batley, J. R.
AU - Beaudoin, G.
AU - Beck, A.
AU - Beck, G. A.
AU - Becker, J.
AU - Beeston, C.
AU - Behnke, T.
AU - Bell, K. W.
AU - Bella, G.
AU - Bentkowski, P.
AU - Berlich, P.
AU - Bethke, S.
AU - Biebel, O.
AU - Bloodworth, I. J.
AU - Bock, P.
AU - Boden, B.
AU - Bosch, H. M.
AU - Boutemeur, M.
AU - Breuker, H.
AU - Bright-Thomas, P.
AU - Brown, R. M.
AU - Buijs, A.
AU - Burckhart, H. J.
AU - Burgard, C.
AU - Capiluppi, P.
AU - Carnegie, R. K.
AU - Carter, A. A.
AU - Carter, J. R.
AU - Chang, C. Y.
AU - Charlton, D. G.
AU - Chu, S. L.
AU - Clarke, P. E.L.
AU - Clayton, J. C.
AU - Cohen, I.
AU - Conboy, J. E.
AU - Cooper, M.
AU - Coupland, M.
AU - Cuffiani, M.
AU - Dado, S.
AU - Dallavalle, G. M.
AU - De Jong, S.
AU - del Pozo, L. A.
AU - Deng, H.
AU - Dieckmann, A.
AU - Dittmar, M.
AU - Dixit, M. S.
AU - do Couto e Silva, E.
AU - Duboscq, J. E.
AU - Duchovni, E.
AU - Duckeck, G.
AU - Duerdoth, I. P.
AU - Dumas, D. J.P.
AU - Elcombe, P. A.
AU - Estabrooks, P. G.
AU - Etzion, E.
AU - Evans, H. G.
AU - Fabbri, F.
AU - Fabbro, B.
AU - Fierro, M.
AU - Fincke-Keeler, M.
AU - Fischer, H. M.
AU - Fong, D. G.
AU - Foucher, M.
AU - Gaidot, A.
AU - Gary, J. W.
AU - Gascon, J.
AU - Geddes, N. I.
AU - Geich-Gimbel, C.
AU - Gensler, S. W.
AU - Gentit, F. X.
AU - Giacomelli, G.
AU - Giacomelli, R.
AU - Gibson, V.
AU - Gibson, W. R.
AU - Gillies, J. D.
AU - Gingrich, D. M.
AU - Goldberg, J.
AU - Goodrick, M. J.
AU - Gorn, W.
AU - Grandi, C.
AU - Grant, F. C.
AU - Hagemann, J.
AU - Hanson, G. G.
AU - Hansroul, M.
AU - Hargrove, C. K.
AU - Harrison, P. F.
AU - Hart, J.
AU - Hattersley, P. M.
AU - Hauschild, M.
AU - Hawkes, C. M.
AU - Heflin, E.
AU - Hemingway, R. J.
AU - Herten, G.
AU - Heuer, R. D.
AU - Hill, J. C.
AU - Hillier, S. J.
AU - Hilse, T.
AU - Hinshaw, D. A.
AU - Hobbs, J. D.
AU - Hobson, P. R.
AU - Hochman, D.
AU - Homer, R. J.
AU - Honma, A. K.
AU - Hughes-Jones, R. E.
AU - Humbert, R.
AU - Igo-Kemenes, P.
AU - Ihssen, H.
AU - Imrie, D. C.
AU - Janissen, A. C.
AU - Jawahery, A.
AU - Jeffreys, P. W.
AU - Jeremie, H.
AU - Jimack, M.
AU - Jones, M.
AU - Jones, R. W.L.
AU - Jovanovic, P.
AU - Jui, C.
AU - Karlen, D.
AU - Kawagoe, K.
AU - Kawamoto, T.
AU - Keeler, R. K.
AU - Kellogg, R. G.
AU - Kennedy, B. W.
AU - Kluth, S.
AU - Kobayashi, T.
AU - Koetke, D. S.
AU - Kokott, T. P.
AU - Komamiya, S.
AU - Köpke, L.
AU - Kral, J. F.
AU - Kowalewski, R.
AU - von Krogh, J.
AU - Kroll, J.
AU - Kuwano, M.
AU - Kyberd, P.
AU - Lafferty, G. D.
AU - Lafoux, H.
AU - Lahmann, R.
AU - Lamarche, F.
AU - Layter, J. G.
AU - Leblanc, P.
AU - Lee, A. M.
AU - Lehto, M. H.
AU - Lellouch, D.
AU - Leroy, C.
AU - Letts, J.
AU - Levegrün, S.
AU - Levinson, L.
AU - Lloyd, S. L.
AU - Loebinger, F. K.
AU - Lorah, J. M.
AU - Lorazo, B.
AU - Losty, M. J.
AU - Lou, X. C.
AU - Ludwig, J.
AU - Luig, A.
AU - Mannelli, M.
AU - Marcellini, S.
AU - Markus, C.
AU - Martin, A. J.
AU - Martin, J. P.
AU - Mashimo, T.
AU - Mättig, P.
AU - Maur, U.
AU - McKenna, J.
AU - McMahon, T. J.
AU - McNutt, J. R.
AU - Meijers, F.
AU - Menszner, D.
AU - Merritt, F. S.
AU - Mes, H.
AU - Michelini, A.
AU - Middleton, R. P.
AU - Mikenberg, G.
AU - Mildenberger, J.
AU - Miller, D. J.
AU - Mir, R.
AU - Mohr, W.
AU - Moisan, C.
AU - Montanari, A.
AU - Mori, T.
AU - Morii, M.
AU - Müller, U.
AU - Nellen, B.
AU - Nguyen, H. H.
AU - O'Neale, S. W.
AU - Oakham, F. G.
AU - Odorici, F.
AU - Orgen, H. O.
AU - Oram, C. J.
AU - Oreglia, M. J.
AU - Orito, S.
AU - Pansart, J. P.
AU - Panzer-Steindel, B.
AU - Paschievici, P.
AU - Patrick, G. N.
AU - Paz-Jaoshvili, N.
AU - Pearce, M. J.
AU - Pfister, P.
AU - Pilcher, J. E.
AU - Pinfold, J.
AU - Pitman, D.
AU - Plane, D. E.
AU - Poffenberger, P.
AU - Poli, B.
AU - Pouladdej, A.
AU - Pritchard, T. W.
AU - Przysiezniak, H.
AU - Quast, G.
AU - Redmond, M. W.
AU - Rees, D. L.
AU - Richards, G. E.
AU - Robins, S. A.
AU - Robinson, D.
AU - Rollnik, A.
AU - Roney, J. M.
AU - Ros, E.
AU - Rossberg, S.
AU - Rossi, A. M.
AU - Rosvick, M.
AU - Routenburg, P.
AU - Runge, K.
AU - Runolfsson, O.
AU - Rust, D. R.
AU - Sasaki, M.
AU - Sbarra, C.
AU - Schaile, A. D.
AU - Schaile, O.
AU - Schappert, W.
AU - Scharff-Hansen, P.
AU - Schenk, P.
AU - Schmitt, B.
AU - von der Schmitt, H.
AU - Schröder, M.
AU - Schwick, C.
AU - Schwiening, J.
AU - Scott, W. G.
AU - Settles, M.
AU - Shears, T. G.
AU - Shen, B. C.
AU - Shepherd-Themistocleous, C. H.
AU - Sherwood, P.
AU - Siroli, G. P.
AU - Skillman, A.
AU - Skuja, A.
AU - Smith, A. M.
AU - Smith, T. J.
AU - Snow, G. A.
AU - Sobie, R.
AU - Springer, R. W.
AU - Sproston, M.
AU - Stahl, A.
AU - Stegmann, C.
AU - Stephens, K.
AU - Steuerer, J.
AU - Ströhmer, R.
AU - Strom, D.
AU - Takeda, H.
AU - Takeshita, T.
AU - Tarem, S.
AU - Tecchio, M.
AU - Teixeira-Dias, P.
AU - Tesch, N.
AU - Thomson, M. A.
AU - Torrente-Lujan, E.
AU - Towers, S.
AU - Transtromer, G.
AU - Tresilian, N. J.
AU - Tsukamoto, T.
AU - Turner, M. F.
AU - Van den plas, D.
AU - Van Kooten, R.
AU - VanDalen, G. J.
AU - Vasseur, G.
AU - Virtue, C. J.
AU - Wagner, A.
AU - Wagner, D. L.
AU - Wahl, C.
AU - Ward, C. P.
AU - Ward, D. R.
AU - Watkins, P. M.
AU - Watson, A. T.
AU - Watson, N. K.
AU - Weber, M.
AU - Weber, P.
AU - Wells, P. S.
AU - Wermes, N.
AU - Whalley, M. A.
AU - Wilkens, B.
AU - Wilson, G. W.
AU - Wilson, J. A.
AU - Winterer, V. H.
AU - Wlodek, T.
AU - Wolf, G.
AU - Wotton, S.
AU - Wyatt, T. R.
AU - Yaari, R.
AU - Yeaman, A.
AU - Yekutieli, G.
AU - Yurko, M.
AU - Zeuner, W.
AU - Zorn, G. T.
N1 - Funding Information: It is a pleasure to thank the SL Division for the efficient operation of the LEP accelerator, the precise information on the absolute energy, and their continuing close cooperation with our experimental group. In addition to the support staff at our own institutions we are pleased to acknowledge the Department of Energy, USA, National Science Foundation, USA, Texas National Research Laboratory Commission, USA, Science and Engineering Research Council, UK, Natural Sciences and Engineering Research Council, Canada, Fussefeld Foundation, Israeli Ministry of Energy and Ministry of Science, Minerva Gesellschaft, Japanese Ministry of Education, Science and Culture (the Monbusho) and a grant under the Monbusho International Science Research Program, German Israeli Bi-national Science Foundation (GIF), Direction des Sciences de la Mati6re du Commissariat fi l'Energie Atomique, France, Bundesministerium fiir Forschung und Technologie, Germany, National Research Council of Canada, A.P. Sloan Foundation and Junta Nacional de Investigaq~o Cient{fica e Tec-nol6gica, Portugal.
PY - 1993/7/29
Y1 - 1993/7/29
N2 - A search for events with photon pairs of large invariant mass is described based on a data sample of 43 pb-1 collected with the OPAL detector. This search is motivated by the L3 observation of four events of the type e+e- → l+l-γγ with an invariant mass of the two photons, mγγ, clustering around 60 GeV. In the OPAL data, four ℓ+ℓ-γγ events are found with mγγ above 40 GeV. The number of observed events is consistent with the QED expectation and no obvious resonance structure is seen. Three candidate qq̄γγ events with mγγ above 40 GeV are found and no νν̄nγγ candidate with mγγ > 5 GeV is found. From these searches an upper limit is set on any anomalous production of ℓ+ℓ-γγ (ℓ = e, μ, τ) events, where the ℓ+ℓ- pair comes from a virtual Z0 and mγγ is near 60 GeV, of B(Z0 → Z*0γγ → ℓ+ℓ-γγ) < 6.0 × 10-7 at the 95% CL. In a similar search in the reaction e+e- → γγγ, seven events are observed with a photon pairing of mass near 60 GeV compared to an expected background of 2.7 ± 0.4 from QED. In a search for the production of a 60 GeV resonance X in two-photon collisions, an upper limit is set on ΓXB2(X → γγ) of 2.6 MeV at the 95% CL. A search is also performed for ℓ+ℓ-X (ℓ = e, μ) events in non-γγ decay modes of X. No indication of a 60 GeV resonance is seen. Combining these two searches, ΓX values greater than 110 MeV are excluded at the 95% CL for ℓ+ℓ-γγ (ℓ = e, μ) cross-sections greater than 0.05 pb.
AB - A search for events with photon pairs of large invariant mass is described based on a data sample of 43 pb-1 collected with the OPAL detector. This search is motivated by the L3 observation of four events of the type e+e- → l+l-γγ with an invariant mass of the two photons, mγγ, clustering around 60 GeV. In the OPAL data, four ℓ+ℓ-γγ events are found with mγγ above 40 GeV. The number of observed events is consistent with the QED expectation and no obvious resonance structure is seen. Three candidate qq̄γγ events with mγγ above 40 GeV are found and no νν̄nγγ candidate with mγγ > 5 GeV is found. From these searches an upper limit is set on any anomalous production of ℓ+ℓ-γγ (ℓ = e, μ, τ) events, where the ℓ+ℓ- pair comes from a virtual Z0 and mγγ is near 60 GeV, of B(Z0 → Z*0γγ → ℓ+ℓ-γγ) < 6.0 × 10-7 at the 95% CL. In a similar search in the reaction e+e- → γγγ, seven events are observed with a photon pairing of mass near 60 GeV compared to an expected background of 2.7 ± 0.4 from QED. In a search for the production of a 60 GeV resonance X in two-photon collisions, an upper limit is set on ΓXB2(X → γγ) of 2.6 MeV at the 95% CL. A search is also performed for ℓ+ℓ-X (ℓ = e, μ) events in non-γγ decay modes of X. No indication of a 60 GeV resonance is seen. Combining these two searches, ΓX values greater than 110 MeV are excluded at the 95% CL for ℓ+ℓ-γγ (ℓ = e, μ) cross-sections greater than 0.05 pb.
UR - http://www.scopus.com/inward/record.url?scp=0001478122&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=0001478122&partnerID=8YFLogxK
U2 - 10.1016/0370-2693(93)90586-7
DO - 10.1016/0370-2693(93)90586-7
M3 - Article
AN - SCOPUS:0001478122
SN - 0370-2693
VL - 311
SP - 391
EP - 407
JO - Physics Letters B
JF - Physics Letters B
IS - 1-4
ER -