Search for anomalous production of high mass photon pairs in e+e- collisions at LEP

P. D. Acton, R. Akers, G. Alexander, J. Allison, K. J. Anderson, S. Arcelli, A. Astbury, D. Axen, G. Azuelos, J. T.M. Baines, A. H. Ball, J. Banks, R. J. Barlow, S. Barnett, R. Bartoldus, J. R. Batley, G. Beaudoin, A. Beck, G. A. Beck, J. BeckerC. Beeston, T. Behnke, K. W. Bell, G. Bella, P. Bentkowski, P. Berlich, S. Bethke, O. Biebel, I. J. Bloodworth, P. Bock, B. Boden, H. M. Bosch, M. Boutemeur, H. Breuker, P. Bright-Thomas, R. M. Brown, A. Buijs, H. J. Burckhart, C. Burgard, P. Capiluppi, R. K. Carnegie, A. A. Carter, J. R. Carter, C. Y. Chang, D. G. Charlton, S. L. Chu, P. E.L. Clarke, J. C. Clayton, I. Cohen, J. E. Conboy, M. Cooper, M. Coupland, M. Cuffiani, S. Dado, G. M. Dallavalle, S. De Jong, L. A. del Pozo, H. Deng, A. Dieckmann, M. Dittmar, M. S. Dixit, E. do Couto e Silva, J. E. Duboscq, E. Duchovni, G. Duckeck, I. P. Duerdoth, D. J.P. Dumas, P. A. Elcombe, P. G. Estabrooks, E. Etzion, H. G. Evans, F. Fabbri, B. Fabbro, M. Fierro, M. Fincke-Keeler, H. M. Fischer, D. G. Fong, M. Foucher, A. Gaidot, J. W. Gary, J. Gascon, N. I. Geddes, C. Geich-Gimbel, S. W. Gensler, F. X. Gentit, G. Giacomelli, R. Giacomelli, V. Gibson, W. R. Gibson, J. D. Gillies, D. M. Gingrich, J. Goldberg, M. J. Goodrick, W. Gorn, C. Grandi, F. C. Grant, J. Hagemann, G. G. Hanson, M. Hansroul, C. K. Hargrove, P. F. Harrison, J. Hart, P. M. Hattersley, M. Hauschild, C. M. Hawkes, E. Heflin, R. J. Hemingway, G. Herten, R. D. Heuer, J. C. Hill, S. J. Hillier, T. Hilse, D. A. Hinshaw, J. D. Hobbs, P. R. Hobson, D. Hochman, R. J. Homer, A. K. Honma, R. E. Hughes-Jones, R. Humbert, P. Igo-Kemenes, H. Ihssen, D. C. Imrie, A. C. Janissen, A. Jawahery, P. W. Jeffreys, H. Jeremie, M. Jimack, M. Jones, R. W.L. Jones, P. Jovanovic, C. Jui, D. Karlen, K. Kawagoe, T. Kawamoto, R. K. Keeler, R. G. Kellogg, B. W. Kennedy, S. Kluth, T. Kobayashi, D. S. Koetke, T. P. Kokott, Sachio Komamiya, L. Köpke, J. F. Kral, R. Kowalewski, J. von Krogh, J. Kroll, M. Kuwano, P. Kyberd, G. D. Lafferty, H. Lafoux, R. Lahmann, F. Lamarche, J. G. Layter, P. Leblanc, A. M. Lee, M. H. Lehto, D. Lellouch, C. Leroy, J. Letts, S. Levegrün, L. Levinson, S. L. Lloyd, F. K. Loebinger, J. M. Lorah, B. Lorazo, M. J. Losty, X. C. Lou, J. Ludwig, A. Luig, M. Mannelli, S. Marcellini, C. Markus, A. J. Martin, J. P. Martin, T. Mashimo, P. Mättig, U. Maur, J. McKenna, T. J. McMahon, J. R. McNutt, F. Meijers, D. Menszner, F. S. Merritt, H. Mes, A. Michelini, R. P. Middleton, G. Mikenberg, J. Mildenberger, D. J. Miller, R. Mir, W. Mohr, C. Moisan, A. Montanari, T. Mori, M. Morii, U. Müller, B. Nellen, H. H. Nguyen, S. W. O'Neale, F. G. Oakham, F. Odorici, H. O. Orgen, C. J. Oram, M. J. Oreglia, S. Orito, J. P. Pansart, B. Panzer-Steindel, P. Paschievici, G. N. Patrick, N. Paz-Jaoshvili, M. J. Pearce, P. Pfister, J. E. Pilcher, J. Pinfold, D. Pitman, D. E. Plane, P. Poffenberger, B. Poli, A. Pouladdej, T. W. Pritchard, H. Przysiezniak, G. Quast, M. W. Redmond, D. L. Rees, G. E. Richards, S. A. Robins, D. Robinson, A. Rollnik, J. M. Roney, E. Ros, S. Rossberg, A. M. Rossi, M. Rosvick, P. Routenburg, K. Runge, O. Runolfsson, D. R. Rust, M. Sasaki, C. Sbarra, A. D. Schaile, O. Schaile, W. Schappert, P. Scharff-Hansen, P. Schenk, B. Schmitt, H. von der Schmitt, M. Schröder, C. Schwick, J. Schwiening, W. G. Scott, M. Settles, T. G. Shears, B. C. Shen, C. H. Shepherd-Themistocleous, P. Sherwood, G. P. Siroli, A. Skillman, A. Skuja, A. M. Smith, T. J. Smith, G. A. Snow, R. Sobie, R. W. Springer, M. Sproston, A. Stahl, C. Stegmann, K. Stephens, J. Steuerer, R. Ströhmer, D. Strom, H. Takeda, T. Takeshita, S. Tarem, M. Tecchio, P. Teixeira-Dias, N. Tesch, M. A. Thomson, E. Torrente-Lujan, S. Towers, G. Transtromer, N. J. Tresilian, T. Tsukamoto, M. F. Turner, D. Van den plas, R. Van Kooten, G. J. VanDalen, G. Vasseur, C. J. Virtue, A. Wagner, D. L. Wagner, C. Wahl, C. P. Ward, D. R. Ward, P. M. Watkins, A. T. Watson, N. K. Watson, M. Weber, P. Weber, P. S. Wells, N. Wermes, M. A. Whalley, B. Wilkens, G. W. Wilson, J. A. Wilson, V. H. Winterer, T. Wlodek, G. Wolf, S. Wotton, T. R. Wyatt, R. Yaari, A. Yeaman, G. Yekutieli, M. Yurko, W. Zeuner, G. T. Zorn

Research output: Contribution to journalArticle

34 Citations (Scopus)

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+-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 νν&#x0304;nγγ candidate with mγγ > 5 GeV is found. From these searches an upper limit is set on any anomalous production of ℓ+-γγ (ℓ = e, μ, τ) events, where the ℓ+- pair comes from a virtual Z0 and mγγ is near 60 GeV, of B(Z0 → Z*0γγ → 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+-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+-γγ (ℓ = e, μ) cross-sections greater than 0.05 pb.

Original languageEnglish
Pages (from-to)391-407
Number of pages17
JournalPhysics Letters B
Volume311
Issue number1-4
DOIs
Publication statusPublished - 1993 Jul 29
Externally publishedYes

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collisions
photons
indication
detectors
cross sections
decay

ASJC Scopus subject areas

  • Nuclear and High Energy Physics

Cite this

Acton, P. D., Akers, R., Alexander, G., Allison, J., Anderson, K. J., Arcelli, S., ... Zorn, G. T. (1993). Search for anomalous production of high mass photon pairs in e+e- collisions at LEP. Physics Letters B, 311(1-4), 391-407. https://doi.org/10.1016/0370-2693(93)90586-7

Search for anomalous production of high mass photon pairs in e+e- collisions at LEP. / Acton, P. D.; Akers, R.; Alexander, G.; Allison, J.; Anderson, K. J.; Arcelli, S.; Astbury, A.; Axen, D.; Azuelos, G.; Baines, J. T.M.; Ball, A. H.; Banks, J.; Barlow, R. J.; Barnett, S.; Bartoldus, R.; Batley, J. R.; Beaudoin, G.; Beck, A.; Beck, G. A.; Becker, J.; Beeston, C.; Behnke, T.; Bell, K. W.; Bella, G.; Bentkowski, P.; Berlich, P.; Bethke, S.; Biebel, O.; Bloodworth, I. J.; Bock, P.; Boden, B.; Bosch, H. M.; Boutemeur, M.; Breuker, H.; Bright-Thomas, P.; Brown, R. M.; Buijs, A.; Burckhart, H. J.; Burgard, C.; Capiluppi, P.; Carnegie, R. K.; Carter, A. A.; Carter, J. R.; Chang, C. Y.; Charlton, D. G.; Chu, S. L.; Clarke, P. E.L.; Clayton, J. C.; Cohen, I.; Conboy, J. E.; Cooper, M.; Coupland, M.; Cuffiani, M.; Dado, S.; Dallavalle, G. M.; De Jong, S.; del Pozo, L. A.; Deng, H.; Dieckmann, A.; Dittmar, M.; Dixit, M. S.; do Couto e Silva, E.; Duboscq, J. E.; Duchovni, E.; Duckeck, G.; Duerdoth, I. P.; Dumas, D. J.P.; Elcombe, P. A.; Estabrooks, P. G.; Etzion, E.; Evans, H. G.; Fabbri, F.; Fabbro, B.; Fierro, M.; Fincke-Keeler, M.; Fischer, H. M.; Fong, D. G.; Foucher, M.; Gaidot, A.; Gary, J. W.; Gascon, J.; Geddes, N. I.; Geich-Gimbel, C.; Gensler, S. W.; Gentit, F. X.; Giacomelli, G.; Giacomelli, R.; Gibson, V.; Gibson, W. R.; Gillies, J. D.; Gingrich, D. M.; Goldberg, J.; Goodrick, M. J.; Gorn, W.; Grandi, C.; Grant, F. C.; Hagemann, J.; Hanson, G. G.; Hansroul, M.; Hargrove, C. K.; Harrison, P. F.; Hart, J.; Hattersley, P. M.; Hauschild, M.; Hawkes, C. M.; Heflin, E.; Hemingway, R. J.; Herten, G.; Heuer, R. D.; Hill, J. C.; Hillier, S. J.; Hilse, T.; Hinshaw, D. A.; Hobbs, J. D.; Hobson, P. R.; Hochman, D.; Homer, R. J.; Honma, A. K.; Hughes-Jones, R. E.; Humbert, R.; Igo-Kemenes, P.; Ihssen, H.; Imrie, D. C.; Janissen, A. C.; Jawahery, A.; Jeffreys, P. W.; Jeremie, H.; Jimack, M.; Jones, M.; Jones, R. W.L.; Jovanovic, P.; Jui, C.; Karlen, D.; Kawagoe, K.; Kawamoto, T.; Keeler, R. K.; Kellogg, R. G.; Kennedy, B. W.; Kluth, S.; Kobayashi, T.; Koetke, D. S.; Kokott, T. P.; Komamiya, Sachio; Köpke, L.; Kral, J. F.; Kowalewski, R.; von Krogh, J.; Kroll, J.; Kuwano, M.; Kyberd, P.; Lafferty, G. D.; Lafoux, H.; Lahmann, R.; Lamarche, F.; Layter, J. G.; Leblanc, P.; Lee, A. M.; Lehto, M. H.; Lellouch, D.; Leroy, C.; Letts, J.; Levegrün, S.; Levinson, L.; Lloyd, S. L.; Loebinger, F. K.; Lorah, J. M.; Lorazo, B.; Losty, M. J.; Lou, X. C.; Ludwig, J.; Luig, A.; Mannelli, M.; Marcellini, S.; Markus, C.; Martin, A. J.; Martin, J. P.; Mashimo, T.; Mättig, P.; Maur, U.; McKenna, J.; McMahon, T. J.; McNutt, J. R.; Meijers, F.; Menszner, D.; Merritt, F. S.; Mes, H.; Michelini, A.; Middleton, R. P.; Mikenberg, G.; Mildenberger, J.; Miller, D. J.; Mir, R.; Mohr, W.; Moisan, C.; Montanari, A.; Mori, T.; Morii, M.; Müller, U.; Nellen, B.; Nguyen, H. H.; O'Neale, S. W.; Oakham, F. G.; Odorici, F.; Orgen, H. O.; Oram, C. J.; Oreglia, M. J.; Orito, S.; Pansart, J. P.; Panzer-Steindel, B.; Paschievici, P.; Patrick, G. N.; Paz-Jaoshvili, N.; Pearce, M. J.; Pfister, P.; Pilcher, J. E.; Pinfold, J.; Pitman, D.; Plane, D. E.; Poffenberger, P.; Poli, B.; Pouladdej, A.; Pritchard, T. W.; Przysiezniak, H.; Quast, G.; Redmond, M. W.; Rees, D. L.; Richards, G. E.; Robins, S. A.; Robinson, D.; Rollnik, A.; Roney, J. M.; Ros, E.; Rossberg, S.; Rossi, A. M.; Rosvick, M.; Routenburg, P.; Runge, K.; Runolfsson, O.; Rust, D. R.; Sasaki, M.; Sbarra, C.; Schaile, A. D.; Schaile, O.; Schappert, W.; Scharff-Hansen, P.; Schenk, P.; Schmitt, B.; von der Schmitt, H.; Schröder, M.; Schwick, C.; Schwiening, J.; Scott, W. G.; Settles, M.; Shears, T. G.; Shen, B. C.; Shepherd-Themistocleous, C. H.; Sherwood, P.; Siroli, G. P.; Skillman, A.; Skuja, A.; Smith, A. M.; Smith, T. J.; Snow, G. A.; Sobie, R.; Springer, R. W.; Sproston, M.; Stahl, A.; Stegmann, C.; Stephens, K.; Steuerer, J.; Ströhmer, R.; Strom, D.; Takeda, H.; Takeshita, T.; Tarem, S.; Tecchio, M.; Teixeira-Dias, P.; Tesch, N.; Thomson, M. A.; Torrente-Lujan, E.; Towers, S.; Transtromer, G.; Tresilian, N. J.; Tsukamoto, T.; Turner, M. F.; Van den plas, D.; Van Kooten, R.; VanDalen, G. J.; Vasseur, G.; Virtue, C. J.; Wagner, A.; Wagner, D. L.; Wahl, C.; Ward, C. P.; Ward, D. R.; Watkins, P. M.; Watson, A. T.; Watson, N. K.; Weber, M.; Weber, P.; Wells, P. S.; Wermes, N.; Whalley, M. A.; Wilkens, B.; Wilson, G. W.; Wilson, J. A.; Winterer, V. H.; Wlodek, T.; Wolf, G.; Wotton, S.; Wyatt, T. R.; Yaari, R.; Yeaman, A.; Yekutieli, G.; Yurko, M.; Zeuner, W.; Zorn, G. T.

In: Physics Letters B, Vol. 311, No. 1-4, 29.07.1993, p. 391-407.

Research output: Contribution to journalArticle

Acton, PD, Akers, R, Alexander, G, Allison, J, Anderson, KJ, Arcelli, S, Astbury, A, Axen, D, Azuelos, G, Baines, JTM, Ball, AH, Banks, J, Barlow, RJ, Barnett, S, Bartoldus, R, Batley, JR, Beaudoin, G, Beck, A, Beck, GA, Becker, J, Beeston, C, Behnke, T, Bell, KW, Bella, G, Bentkowski, P, Berlich, P, Bethke, S, Biebel, O, Bloodworth, IJ, Bock, P, Boden, B, Bosch, HM, Boutemeur, M, Breuker, H, Bright-Thomas, P, Brown, RM, Buijs, A, Burckhart, HJ, Burgard, C, Capiluppi, P, Carnegie, RK, Carter, AA, Carter, JR, Chang, CY, Charlton, DG, Chu, SL, Clarke, PEL, Clayton, JC, Cohen, I, Conboy, JE, Cooper, M, Coupland, M, Cuffiani, M, Dado, S, Dallavalle, GM, De Jong, S, del Pozo, LA, Deng, H, Dieckmann, A, Dittmar, M, Dixit, MS, do Couto e Silva, E, Duboscq, JE, Duchovni, E, Duckeck, G, Duerdoth, IP, Dumas, DJP, Elcombe, PA, Estabrooks, PG, Etzion, E, Evans, HG, Fabbri, F, Fabbro, B, Fierro, M, Fincke-Keeler, M, Fischer, HM, Fong, DG, Foucher, M, Gaidot, A, Gary, JW, Gascon, J, Geddes, NI, Geich-Gimbel, C, Gensler, SW, Gentit, FX, Giacomelli, G, Giacomelli, R, Gibson, V, Gibson, WR, Gillies, JD, Gingrich, DM, Goldberg, J, Goodrick, MJ, Gorn, W, Grandi, C, Grant, FC, Hagemann, J, Hanson, GG, Hansroul, M, Hargrove, CK, Harrison, PF, Hart, J, Hattersley, PM, Hauschild, M, Hawkes, CM, Heflin, E, Hemingway, RJ, Herten, G, Heuer, RD, Hill, JC, Hillier, SJ, Hilse, T, Hinshaw, DA, Hobbs, JD, Hobson, PR, Hochman, D, Homer, RJ, Honma, AK, Hughes-Jones, RE, Humbert, R, Igo-Kemenes, P, Ihssen, H, Imrie, DC, Janissen, AC, Jawahery, A, Jeffreys, PW, Jeremie, H, Jimack, M, Jones, M, Jones, RWL, Jovanovic, P, Jui, C, Karlen, D, Kawagoe, K, Kawamoto, T, Keeler, RK, Kellogg, RG, Kennedy, BW, Kluth, S, Kobayashi, T, Koetke, DS, Kokott, TP, Komamiya, S, Köpke, L, Kral, JF, Kowalewski, R, von Krogh, J, Kroll, J, Kuwano, M, Kyberd, P, Lafferty, GD, Lafoux, H, Lahmann, R, Lamarche, F, Layter, JG, Leblanc, P, Lee, AM, Lehto, MH, Lellouch, D, Leroy, C, Letts, J, Levegrün, S, Levinson, L, Lloyd, SL, Loebinger, FK, Lorah, JM, Lorazo, B, Losty, MJ, Lou, XC, Ludwig, J, Luig, A, Mannelli, M, Marcellini, S, Markus, C, Martin, AJ, Martin, JP, Mashimo, T, Mättig, P, Maur, U, McKenna, J, McMahon, TJ, McNutt, JR, Meijers, F, Menszner, D, Merritt, FS, Mes, H, Michelini, A, Middleton, RP, Mikenberg, G, Mildenberger, J, Miller, DJ, Mir, R, Mohr, W, Moisan, C, Montanari, A, Mori, T, Morii, M, Müller, U, Nellen, B, Nguyen, HH, O'Neale, SW, Oakham, FG, Odorici, F, Orgen, HO, Oram, CJ, Oreglia, MJ, Orito, S, Pansart, JP, Panzer-Steindel, B, Paschievici, P, Patrick, GN, Paz-Jaoshvili, N, Pearce, MJ, Pfister, P, Pilcher, JE, Pinfold, J, Pitman, D, Plane, DE, Poffenberger, P, Poli, B, Pouladdej, A, Pritchard, TW, Przysiezniak, H, Quast, G, Redmond, MW, Rees, DL, Richards, GE, Robins, SA, Robinson, D, Rollnik, A, Roney, JM, Ros, E, Rossberg, S, Rossi, AM, Rosvick, M, Routenburg, P, Runge, K, Runolfsson, O, Rust, DR, Sasaki, M, Sbarra, C, Schaile, AD, Schaile, O, Schappert, W, Scharff-Hansen, P, Schenk, P, Schmitt, B, von der Schmitt, H, Schröder, M, Schwick, C, Schwiening, J, Scott, WG, Settles, M, Shears, TG, Shen, BC, Shepherd-Themistocleous, CH, Sherwood, P, Siroli, GP, Skillman, A, Skuja, A, Smith, AM, Smith, TJ, Snow, GA, Sobie, R, Springer, RW, Sproston, M, Stahl, A, Stegmann, C, Stephens, K, Steuerer, J, Ströhmer, R, Strom, D, Takeda, H, Takeshita, T, Tarem, S, Tecchio, M, Teixeira-Dias, P, Tesch, N, Thomson, MA, Torrente-Lujan, E, Towers, S, Transtromer, G, Tresilian, NJ, Tsukamoto, T, Turner, MF, Van den plas, D, Van Kooten, R, VanDalen, GJ, Vasseur, G, Virtue, CJ, Wagner, A, Wagner, DL, Wahl, C, Ward, CP, Ward, DR, Watkins, PM, Watson, AT, Watson, NK, Weber, M, Weber, P, Wells, PS, Wermes, N, Whalley, MA, Wilkens, B, Wilson, GW, Wilson, JA, Winterer, VH, Wlodek, T, Wolf, G, Wotton, S, Wyatt, TR, Yaari, R, Yeaman, A, Yekutieli, G, Yurko, M, Zeuner, W & Zorn, GT 1993, 'Search for anomalous production of high mass photon pairs in e+e- collisions at LEP', Physics Letters B, vol. 311, no. 1-4, pp. 391-407. https://doi.org/10.1016/0370-2693(93)90586-7
Acton PD, Akers R, Alexander G, Allison J, Anderson KJ, Arcelli S et al. Search for anomalous production of high mass photon pairs in e+e- collisions at LEP. Physics Letters B. 1993 Jul 29;311(1-4):391-407. https://doi.org/10.1016/0370-2693(93)90586-7
Acton, P. D. ; Akers, R. ; Alexander, G. ; Allison, J. ; Anderson, K. J. ; Arcelli, S. ; Astbury, A. ; Axen, D. ; Azuelos, G. ; Baines, J. T.M. ; Ball, A. H. ; Banks, J. ; Barlow, R. J. ; Barnett, S. ; Bartoldus, R. ; Batley, J. R. ; Beaudoin, G. ; Beck, A. ; Beck, G. A. ; Becker, J. ; Beeston, C. ; Behnke, T. ; Bell, K. W. ; Bella, G. ; Bentkowski, P. ; Berlich, P. ; Bethke, S. ; Biebel, O. ; Bloodworth, I. J. ; Bock, P. ; Boden, B. ; Bosch, H. M. ; Boutemeur, M. ; Breuker, H. ; Bright-Thomas, P. ; Brown, R. M. ; Buijs, A. ; Burckhart, H. J. ; Burgard, C. ; Capiluppi, P. ; Carnegie, R. K. ; Carter, A. A. ; Carter, J. R. ; Chang, C. Y. ; Charlton, D. G. ; Chu, S. L. ; Clarke, P. E.L. ; Clayton, J. C. ; Cohen, I. ; Conboy, J. E. ; Cooper, M. ; Coupland, M. ; Cuffiani, M. ; Dado, S. ; Dallavalle, G. M. ; De Jong, S. ; del Pozo, L. A. ; Deng, H. ; Dieckmann, A. ; Dittmar, M. ; Dixit, M. S. ; do Couto e Silva, E. ; Duboscq, J. E. ; Duchovni, E. ; Duckeck, G. ; Duerdoth, I. P. ; Dumas, D. J.P. ; Elcombe, P. A. ; Estabrooks, P. G. ; Etzion, E. ; Evans, H. G. ; Fabbri, F. ; Fabbro, B. ; Fierro, M. ; Fincke-Keeler, M. ; Fischer, H. M. ; Fong, D. G. ; Foucher, M. ; Gaidot, A. ; Gary, J. W. ; Gascon, J. ; Geddes, N. I. ; Geich-Gimbel, C. ; Gensler, S. W. ; Gentit, F. X. ; Giacomelli, G. ; Giacomelli, R. ; Gibson, V. ; Gibson, W. R. ; Gillies, J. D. ; Gingrich, D. M. ; Goldberg, J. ; Goodrick, M. J. ; Gorn, W. ; Grandi, C. ; Grant, F. C. ; Hagemann, J. ; Hanson, G. G. ; Hansroul, M. ; Hargrove, C. K. ; Harrison, P. F. ; Hart, J. ; Hattersley, P. M. ; Hauschild, M. ; Hawkes, C. M. ; Heflin, E. ; Hemingway, R. J. ; Herten, G. ; Heuer, R. D. ; Hill, J. C. ; Hillier, S. J. ; Hilse, T. ; Hinshaw, D. A. ; Hobbs, J. D. ; Hobson, P. R. ; Hochman, D. ; Homer, R. J. ; Honma, A. K. ; Hughes-Jones, R. E. ; Humbert, R. ; Igo-Kemenes, P. ; Ihssen, H. ; Imrie, D. C. ; Janissen, A. C. ; Jawahery, A. ; Jeffreys, P. W. ; Jeremie, H. ; Jimack, M. ; Jones, M. ; Jones, R. W.L. ; Jovanovic, P. ; Jui, C. ; Karlen, D. ; Kawagoe, K. ; Kawamoto, T. ; Keeler, R. K. ; Kellogg, R. G. ; Kennedy, B. W. ; Kluth, S. ; Kobayashi, T. ; Koetke, D. S. ; Kokott, T. P. ; Komamiya, Sachio ; Köpke, L. ; Kral, J. F. ; Kowalewski, R. ; von Krogh, J. ; Kroll, J. ; Kuwano, M. ; Kyberd, P. ; Lafferty, G. D. ; Lafoux, H. ; Lahmann, R. ; Lamarche, F. ; Layter, J. G. ; Leblanc, P. ; Lee, A. M. ; Lehto, M. H. ; Lellouch, D. ; Leroy, C. ; Letts, J. ; Levegrün, S. ; Levinson, L. ; Lloyd, S. L. ; Loebinger, F. K. ; Lorah, J. M. ; Lorazo, B. ; Losty, M. J. ; Lou, X. C. ; Ludwig, J. ; Luig, A. ; Mannelli, M. ; Marcellini, S. ; Markus, C. ; Martin, A. J. ; Martin, J. P. ; Mashimo, T. ; Mättig, P. ; Maur, U. ; McKenna, J. ; McMahon, T. J. ; McNutt, J. R. ; Meijers, F. ; Menszner, D. ; Merritt, F. S. ; Mes, H. ; Michelini, A. ; Middleton, R. P. ; Mikenberg, G. ; Mildenberger, J. ; Miller, D. J. ; Mir, R. ; Mohr, W. ; Moisan, C. ; Montanari, A. ; Mori, T. ; Morii, M. ; Müller, U. ; Nellen, B. ; Nguyen, H. H. ; O'Neale, S. W. ; Oakham, F. G. ; Odorici, F. ; Orgen, H. O. ; Oram, C. J. ; Oreglia, M. J. ; Orito, S. ; Pansart, J. P. ; Panzer-Steindel, B. ; Paschievici, P. ; Patrick, G. N. ; Paz-Jaoshvili, N. ; Pearce, M. J. ; Pfister, P. ; Pilcher, J. E. ; Pinfold, J. ; Pitman, D. ; Plane, D. E. ; Poffenberger, P. ; Poli, B. ; Pouladdej, A. ; Pritchard, T. W. ; Przysiezniak, H. ; Quast, G. ; Redmond, M. W. ; Rees, D. L. ; Richards, G. E. ; Robins, S. A. ; Robinson, D. ; Rollnik, A. ; Roney, J. M. ; Ros, E. ; Rossberg, S. ; Rossi, A. M. ; Rosvick, M. ; Routenburg, P. ; Runge, K. ; Runolfsson, O. ; Rust, D. R. ; Sasaki, M. ; Sbarra, C. ; Schaile, A. D. ; Schaile, O. ; Schappert, W. ; Scharff-Hansen, P. ; Schenk, P. ; Schmitt, B. ; von der Schmitt, H. ; Schröder, M. ; Schwick, C. ; Schwiening, J. ; Scott, W. G. ; Settles, M. ; Shears, T. G. ; Shen, B. C. ; Shepherd-Themistocleous, C. H. ; Sherwood, P. ; Siroli, G. P. ; Skillman, A. ; Skuja, A. ; Smith, A. M. ; Smith, T. J. ; Snow, G. A. ; Sobie, R. ; Springer, R. W. ; Sproston, M. ; Stahl, A. ; Stegmann, C. ; Stephens, K. ; Steuerer, J. ; Ströhmer, R. ; Strom, D. ; Takeda, H. ; Takeshita, T. ; Tarem, S. ; Tecchio, M. ; Teixeira-Dias, P. ; Tesch, N. ; Thomson, M. A. ; Torrente-Lujan, E. ; Towers, S. ; Transtromer, G. ; Tresilian, N. J. ; Tsukamoto, T. ; Turner, M. F. ; Van den plas, D. ; Van Kooten, R. ; VanDalen, G. J. ; Vasseur, G. ; Virtue, C. J. ; Wagner, A. ; Wagner, D. L. ; Wahl, C. ; Ward, C. P. ; Ward, D. R. ; Watkins, P. M. ; Watson, A. T. ; Watson, N. K. ; Weber, M. ; Weber, P. ; Wells, P. S. ; Wermes, N. ; Whalley, M. A. ; Wilkens, B. ; Wilson, G. W. ; Wilson, J. A. ; Winterer, V. H. ; Wlodek, T. ; Wolf, G. ; Wotton, S. ; Wyatt, T. R. ; Yaari, R. ; Yeaman, A. ; Yekutieli, G. ; Yurko, M. ; Zeuner, W. ; Zorn, G. T. / Search for anomalous production of high mass photon pairs in e+e- collisions at LEP. In: Physics Letters B. 1993 ; Vol. 311, No. 1-4. pp. 391-407.
@article{c27054cfb3d7487e8f2318cfc191cd86,
title = "Search for anomalous production of high mass photon pairs in e+e- collisions at LEP",
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.",
author = "Acton, {P. D.} and R. Akers and G. Alexander and J. Allison and Anderson, {K. J.} and S. Arcelli and A. Astbury and D. Axen and G. Azuelos and Baines, {J. T.M.} and Ball, {A. H.} and J. Banks and Barlow, {R. J.} and S. Barnett and R. Bartoldus and Batley, {J. R.} and G. Beaudoin and A. Beck and Beck, {G. A.} and J. Becker and C. Beeston and T. Behnke and Bell, {K. W.} and G. Bella and P. Bentkowski and P. Berlich and S. Bethke and O. Biebel and Bloodworth, {I. J.} and P. Bock and B. Boden and Bosch, {H. M.} and M. Boutemeur and H. Breuker and P. Bright-Thomas and Brown, {R. M.} and A. Buijs and Burckhart, {H. J.} and C. Burgard and P. Capiluppi and Carnegie, {R. K.} and Carter, {A. A.} and Carter, {J. R.} and Chang, {C. Y.} and Charlton, {D. G.} and Chu, {S. L.} and Clarke, {P. E.L.} and Clayton, {J. C.} and I. Cohen and Conboy, {J. E.} and M. Cooper and M. Coupland and M. Cuffiani and S. Dado and Dallavalle, {G. M.} and {De Jong}, S. and {del Pozo}, {L. A.} and H. Deng and A. Dieckmann and M. Dittmar and Dixit, {M. S.} and {do Couto e Silva}, E. and Duboscq, {J. E.} and E. Duchovni and G. Duckeck and Duerdoth, {I. P.} and Dumas, {D. J.P.} and Elcombe, {P. A.} and Estabrooks, {P. G.} and E. Etzion and Evans, {H. G.} and F. Fabbri and B. Fabbro and M. Fierro and M. Fincke-Keeler and Fischer, {H. M.} and Fong, {D. G.} and M. Foucher and A. Gaidot and Gary, {J. W.} and J. Gascon and Geddes, {N. I.} and C. Geich-Gimbel and Gensler, {S. W.} and Gentit, {F. X.} and G. Giacomelli and R. Giacomelli and V. Gibson and Gibson, {W. R.} and Gillies, {J. D.} and Gingrich, {D. M.} and J. Goldberg and Goodrick, {M. J.} and W. Gorn and C. Grandi and Grant, {F. C.} and J. Hagemann and Hanson, {G. G.} and M. Hansroul and Hargrove, {C. K.} and Harrison, {P. F.} and J. Hart and Hattersley, {P. M.} and M. Hauschild and Hawkes, {C. M.} and E. Heflin and Hemingway, {R. J.} and G. Herten and Heuer, {R. D.} and Hill, {J. C.} and Hillier, {S. J.} and T. Hilse and Hinshaw, {D. A.} and Hobbs, {J. D.} and Hobson, {P. R.} and D. Hochman and Homer, {R. J.} and Honma, {A. K.} and Hughes-Jones, {R. E.} and R. Humbert and P. Igo-Kemenes and H. Ihssen and Imrie, {D. C.} and Janissen, {A. C.} and A. Jawahery and Jeffreys, {P. W.} and H. Jeremie and M. Jimack and M. Jones and Jones, {R. W.L.} and P. Jovanovic and C. Jui and D. Karlen and K. Kawagoe and T. Kawamoto and Keeler, {R. K.} and Kellogg, {R. G.} and Kennedy, {B. W.} and S. Kluth and T. Kobayashi and Koetke, {D. S.} and Kokott, {T. P.} and Sachio Komamiya and L. K{\"o}pke and Kral, {J. F.} and R. Kowalewski and {von Krogh}, J. and J. Kroll and M. Kuwano and P. Kyberd and Lafferty, {G. D.} and H. Lafoux and R. Lahmann and F. Lamarche and Layter, {J. G.} and P. Leblanc and Lee, {A. M.} and Lehto, {M. H.} and D. Lellouch and C. Leroy and J. Letts and S. Levegr{\"u}n and L. Levinson and Lloyd, {S. L.} and Loebinger, {F. K.} and Lorah, {J. M.} and B. Lorazo and Losty, {M. J.} and Lou, {X. C.} and J. Ludwig and A. Luig and M. Mannelli and S. Marcellini and C. Markus and Martin, {A. J.} and Martin, {J. P.} and T. Mashimo and P. M{\"a}ttig and U. Maur and J. McKenna and McMahon, {T. J.} and McNutt, {J. R.} and F. Meijers and D. Menszner and Merritt, {F. S.} and H. Mes and A. Michelini and Middleton, {R. P.} and G. Mikenberg and J. Mildenberger and Miller, {D. J.} and R. Mir and W. Mohr and C. Moisan and A. Montanari and T. Mori and M. Morii and U. M{\"u}ller and B. Nellen and Nguyen, {H. H.} and O'Neale, {S. W.} and Oakham, {F. G.} and F. Odorici and Orgen, {H. O.} and Oram, {C. J.} and Oreglia, {M. J.} and S. Orito and Pansart, {J. P.} and B. Panzer-Steindel and P. Paschievici and Patrick, {G. N.} and N. Paz-Jaoshvili and Pearce, {M. J.} and P. Pfister and Pilcher, {J. E.} and J. Pinfold and D. Pitman and Plane, {D. E.} and P. Poffenberger and B. Poli and A. Pouladdej and Pritchard, {T. W.} and H. Przysiezniak and G. Quast and Redmond, {M. W.} and Rees, {D. L.} and Richards, {G. E.} and Robins, {S. A.} and D. Robinson and A. Rollnik and Roney, {J. M.} and E. Ros and S. Rossberg and Rossi, {A. M.} and M. Rosvick and P. Routenburg and K. Runge and O. Runolfsson and Rust, {D. R.} and M. Sasaki and C. Sbarra and Schaile, {A. D.} and O. Schaile and W. Schappert and P. Scharff-Hansen and P. Schenk and B. Schmitt and {von der Schmitt}, H. and M. Schr{\"o}der and C. Schwick and J. Schwiening and Scott, {W. G.} and M. Settles and Shears, {T. G.} and Shen, {B. C.} and Shepherd-Themistocleous, {C. H.} and P. Sherwood and Siroli, {G. P.} and A. Skillman and A. Skuja and Smith, {A. M.} and Smith, {T. J.} and Snow, {G. A.} and R. Sobie and Springer, {R. W.} and M. Sproston and A. Stahl and C. Stegmann and K. Stephens and J. Steuerer and R. Str{\"o}hmer and D. Strom and H. Takeda and T. Takeshita and S. Tarem and M. Tecchio and P. Teixeira-Dias and N. Tesch and Thomson, {M. A.} and E. Torrente-Lujan and S. Towers and G. Transtromer and Tresilian, {N. J.} and T. Tsukamoto and Turner, {M. F.} and {Van den plas}, D. and {Van Kooten}, R. and VanDalen, {G. J.} and G. Vasseur and Virtue, {C. J.} and A. Wagner and Wagner, {D. L.} and C. Wahl and Ward, {C. P.} and Ward, {D. R.} and Watkins, {P. M.} and Watson, {A. T.} and Watson, {N. K.} and M. Weber and P. Weber and Wells, {P. S.} and N. Wermes and Whalley, {M. A.} and B. Wilkens and Wilson, {G. W.} and Wilson, {J. A.} and Winterer, {V. H.} and T. Wlodek and G. Wolf and S. Wotton and Wyatt, {T. R.} and R. Yaari and A. Yeaman and G. Yekutieli and M. Yurko and W. Zeuner and Zorn, {G. T.}",
year = "1993",
month = "7",
day = "29",
doi = "10.1016/0370-2693(93)90586-7",
language = "English",
volume = "311",
pages = "391--407",
journal = "Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics",
issn = "0370-2693",
publisher = "Elsevier",
number = "1-4",

}

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.

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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

VL - 311

SP - 391

EP - 407

JO - Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics

JF - Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics

SN - 0370-2693

IS - 1-4

ER -