Photonic events with large missing energy in e+e- collisions at √s =161 GeV

K. Ackerstaff, G. Alexander, J. Allison, N. Altekamp, K. Ametewee, K. J. Anderson, S. Anderson, S. Arcelli, S. Asai, D. Axen, G. Azuelos, A. H. Ball, E. Barberio, R. J. Barlow, R. Bartoldus, J. R. Batley, J. Bechtluft, C. Beeston, T. Behnke, A. N. Bell & 312 others K. W. Bell, G. Bella, S. Bentvelsen, P. Berlich, S. Bethke, O. Biebel, V. Blobel, I. J. Bloodworth, J. E. Bloomer, M. Bobinski, P. Bock, H. M. Bosch, M. Boutemeur, B. T. Bouwens, S. Braibant, R. M. Brown, A. Buguzzi, H. J. Burckhart, C. Burgard, R. Bürgin, P. Capiluppi, R. K. Carnegie, A. A. Carter, J. R. Carter, C. Y. Chang, D. G. Charlton, D. Chrisman, P. E.L. Clarke, I. Cohen, J. E. Conboy, O. C. Cooke, M. Cuffiani, S. Dado, C. Dallapiccola, G. M. Dallavalle, S. de Jong, L. A. del Pozo, K. Desch, M. S. Dixit, E. do Couto e Silva, M. Doucet, E. Duchovni, G. Duckeck, I. P. Duerdoth, J. E.G. Edwards, P. G. Estabrooks, H. G. Evans, M. Evans, F. Fabbri, P. Fath, F. Fiedler, M. Fierro, H. M. Fischer, R. Folman, D. G. Fong, M. Foucher, A. Fürtjes, P. Gagnon, J. W. Gary, J. Gascon, S. M. Gascon-Shotkin, N. I. Geddes, C. Geich-Gimbel, T. Geralis, G. Giacomelli, P. Giacomelli, R. Giacomelli, V. Gibson, W. R. Gibson, D. M. Gingrich, D. Glenzinski, J. Goldberg, M. J. Goodrick, W. Gorn, C. Grandi, E. Gross, J. Grunhaus, M. Gruwé, C. Hajdu, G. G. Hanson, M. Hansroul, M. Hapke, C. K. Hargrove, P. A. Hart, C. Hartmann, M. Hauschild, C. M. Hawkes, R. Hawkings, R. J. Hemingway, M. Herndon, G. Herten, R. D. Heuer, M. D. Hildreth, J. C. Hill, S. J. Hillier, T. Hilse, P. R. Hobson, R. J. Homer, A. K. Honma, D. Horváth, R. Howard, R. E. Hughes-Jones, D. E. Hutchcroft, P. Igo-Kemenes, D. C. Imrie, M. R. Ingram, K. Ishii, A. Jawahery, P. W. Jeffreys, H. Jeremie, M. Jimack, A. Joly, C. R. Jones, G. Jones, M. Jones, R. W.L. Jones, U. Jost, P. Jovanovic, T. R. Junk, D. Karlen, Kiyotomo Kawagoe, T. Kawamoto, R. K. Keeler, R. G. Kellogg, B. W. Kennedy, B. J. King, J. Kirk, S. Kluth, T. Kobayashi, M. Kobel, D. S. Koetke, T. P. Kokott, M. Kolrep, S. Komamiya, T. Kress, P. Krieger, J. von Krogh, P. Kyberd, G. D. Lafferty, R. Lahmann, W. P. Lai, D. Lanske, J. Lauber, S. R. Lautenschlager, J. G. Layter, D. Lazic, A. M. Lee, E. Lefebvre, D. Lellouch, J. Letts, L. Levinson, C. Lewis, S. L. Lloyd, F. K. Loebinger, G. D. Long, M. J. Losty, J. Ludwig, M. Mannelli, S. Marcellini, C. Markus, A. J. Martin, J. P. Martin, G. Martinez, T. Mashimo, W. Matthews, P. Mättig, W. J. McDonald, J. McKenna, E. A. Mckigney, T. J. McMahon, A. I. McNab, R. A. McPherson, F. Meijers, S. Menke, F. S. Merritt, H. Mes, J. Meyer, A. Michelini, G. Mikenberg, D. J. Miller, R. Mir, W. Mohr, A. Montanari, T. Mori, M. Morii, U. Müller, K. Nagai, I. Nakamura, H. A. Neal, B. Nellen, B. Nijjhar, R. Nisius, S. W. O'Neale, F. G. Oakham, F. Odorici, H. O. Ogren, N. J. Oldershaw, T. Omori, M. J. Oreglia, S. Orito, J. Pálinkás, G. Pásztor, J. R. Pater, G. N. Patrick, J. Patt, M. J. Pearce, S. Petzold, P. Pfeifenschneider, J. E. Pilcher, J. Pinfold, D. E. Plane, P. Poffenberger, B. Poli, A. Posthaus, H. Przysiezniak, D. L. Rees, D. Rigby, S. Robertson, S. A. Robins, N. Rodning, J. M. Roney, A. Rooke, E. Ros, A. M. Rossi, M. Rosvick, P. Routenburg, Y. Rozen, K. Runge, O. Runolfsson, U. Ruppel, D. R. Rust, R. Rylko, K. Sachs, E. K.G. Sarkisyan, M. Sasaki, C. Sbarra, A. D. Schaile, O. Schaile, F. Scharf, P. Scharff-Hansen, P. Schenk, B. Schmitt, S. Schmitt, M. Schröder, H. C. Schultz-Coulon, M. Schulz, M. Schumacher, P. Schütz, W. G. Scott, T. G. Shears, B. C. Shen, C. H. Shepherd-Themistocleous, P. Sherwood, G. P. Siroli, A. Sittler, A. Skillman, A. Skuja, A. M. Smith, T. J. Smith, G. A. Snow, R. Sobie, S. Söldner-Rembold, R. W. Springer, M. Sproston, A. Stahl, M. Steiert, K. Stephens, J. Steuerer, B. Stockhausen, D. Strom, F. Strumia, P. Szymanski, R. Tafirout, S. D. Talbot, S. Tanaka, P. Taras, S. Tarem, M. Thiergen, M. A. Thomson, E. von Törne, S. Towers, I. Trigger, T. Tsukamoto, E. Tsur, A. S. Turcot, M. F. Turner-Watson, P. Utzat, R. van Kooten, M. Verzocchi, P. Vikas, M. Vincter, E. H. Vokurka, F. Wäckerle, A. Wagner, C. P. Ward, D. R. Ward, J. J. Ward, P. M. Watkins, A. T. Watson, N. K. Watson, P. S. Wells, N. Wermes, J. S. White, B. Wilkens, G. W. Wilson, J. A. Wilson, G. Wolf, S. Wotton, T. R. Wyatt, S. Yamashita, G. Yekutieli, V. Zacek

Research output: Contribution to journalArticle

19 Citations (Scopus)

Abstract

Photonic events with large missing energy have been observed with the OPAL detector at LEP using two search topologies. The first topology looks for events with significant missing energy and at least one photon in |cos θ| < 0.7 with large scaled energy, xy > 0.2. The second topology looks for events with an acoplanar photon pair where both photons are in |cos θ| < 0.7 and have energy exceeding 1.75 GeV. In the data sample corresponding to an integrated luminosity of 10.0 pb-1, 11 events are selected for the first topology and a cross-section of 1.6 ± 0.5 pb is measured within the kinematic acceptance, consistent with that expected for the Standard Model process e+e- → νν̄γ(γ). No events are selected for the second topology giving a 95% CL cross-section upper limit of 0.41 pb within the kinematic acceptance. Upper limits on the cross-section times branching ratio for new particle production are also derived.

Original languageEnglish
Pages (from-to)210-220
Number of pages11
JournalPhysics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics
Volume391
Issue number1-2
DOIs
Publication statusPublished - Jan 9 1997

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topology
photonics
collisions
acceptability
cross sections
photons
kinematics
energy
particle production
luminosity
detectors

All Science Journal Classification (ASJC) codes

  • Nuclear and High Energy Physics

Cite this

Photonic events with large missing energy in e+e- collisions at √s =161 GeV. / Ackerstaff, K.; Alexander, G.; Allison, J.; Altekamp, N.; Ametewee, K.; Anderson, K. J.; Anderson, S.; Arcelli, S.; Asai, S.; Axen, D.; Azuelos, G.; Ball, A. H.; Barberio, E.; Barlow, R. J.; Bartoldus, R.; Batley, J. R.; Bechtluft, J.; Beeston, C.; Behnke, T.; Bell, A. N.; Bell, K. W.; Bella, G.; Bentvelsen, S.; Berlich, P.; Bethke, S.; Biebel, O.; Blobel, V.; Bloodworth, I. J.; Bloomer, J. E.; Bobinski, M.; Bock, P.; Bosch, H. M.; Boutemeur, M.; Bouwens, B. T.; Braibant, S.; Brown, R. M.; Buguzzi, A.; Burckhart, H. J.; Burgard, C.; Bürgin, R.; Capiluppi, P.; Carnegie, R. K.; Carter, A. A.; Carter, J. R.; Chang, C. Y.; Charlton, D. G.; Chrisman, D.; Clarke, P. E.L.; Cohen, I.; Conboy, J. E.; Cooke, O. C.; Cuffiani, M.; Dado, S.; Dallapiccola, C.; Dallavalle, G. M.; de Jong, S.; del Pozo, L. A.; Desch, K.; Dixit, M. S.; do Couto e Silva, E.; Doucet, M.; Duchovni, E.; Duckeck, G.; Duerdoth, I. P.; Edwards, J. E.G.; Estabrooks, P. G.; Evans, H. G.; Evans, M.; Fabbri, F.; Fath, P.; Fiedler, F.; Fierro, M.; Fischer, H. M.; Folman, R.; Fong, D. G.; Foucher, M.; Fürtjes, A.; Gagnon, P.; Gary, J. W.; Gascon, J.; Gascon-Shotkin, S. M.; Geddes, N. I.; Geich-Gimbel, C.; Geralis, T.; Giacomelli, G.; Giacomelli, P.; Giacomelli, R.; Gibson, V.; Gibson, W. R.; Gingrich, D. M.; Glenzinski, D.; Goldberg, J.; Goodrick, M. J.; Gorn, W.; Grandi, C.; Gross, E.; Grunhaus, J.; Gruwé, M.; Hajdu, C.; Hanson, G. G.; Hansroul, M.; Hapke, M.; Hargrove, C. K.; Hart, P. A.; Hartmann, C.; Hauschild, M.; Hawkes, C. M.; Hawkings, R.; Hemingway, R. J.; Herndon, M.; Herten, G.; Heuer, R. D.; Hildreth, M. D.; Hill, J. C.; Hillier, S. J.; Hilse, T.; Hobson, P. R.; Homer, R. J.; Honma, A. K.; Horváth, D.; Howard, R.; Hughes-Jones, R. E.; Hutchcroft, D. E.; Igo-Kemenes, P.; Imrie, D. C.; Ingram, M. R.; Ishii, K.; Jawahery, A.; Jeffreys, P. W.; Jeremie, H.; Jimack, M.; Joly, A.; Jones, C. R.; Jones, G.; Jones, M.; Jones, R. W.L.; Jost, U.; Jovanovic, P.; Junk, T. R.; Karlen, D.; Kawagoe, Kiyotomo; Kawamoto, T.; Keeler, R. K.; Kellogg, R. G.; Kennedy, B. W.; King, B. J.; Kirk, J.; Kluth, S.; Kobayashi, T.; Kobel, M.; Koetke, D. S.; Kokott, T. P.; Kolrep, M.; Komamiya, S.; Kress, T.; Krieger, P.; von Krogh, J.; Kyberd, P.; Lafferty, G. D.; Lahmann, R.; Lai, W. P.; Lanske, D.; Lauber, J.; Lautenschlager, S. R.; Layter, J. G.; Lazic, D.; Lee, A. M.; Lefebvre, E.; Lellouch, D.; Letts, J.; Levinson, L.; Lewis, C.; Lloyd, S. L.; Loebinger, F. K.; Long, G. D.; Losty, M. J.; Ludwig, J.; Mannelli, M.; Marcellini, S.; Markus, C.; Martin, A. J.; Martin, J. P.; Martinez, G.; Mashimo, T.; Matthews, W.; Mättig, P.; McDonald, W. J.; McKenna, J.; Mckigney, E. A.; McMahon, T. J.; McNab, A. I.; McPherson, R. A.; Meijers, F.; Menke, S.; Merritt, F. S.; Mes, H.; Meyer, J.; Michelini, A.; Mikenberg, G.; Miller, D. J.; Mir, R.; Mohr, W.; Montanari, A.; Mori, T.; Morii, M.; Müller, U.; Nagai, K.; Nakamura, I.; Neal, H. A.; Nellen, B.; Nijjhar, B.; Nisius, R.; O'Neale, S. W.; Oakham, F. G.; Odorici, F.; Ogren, H. O.; Oldershaw, N. J.; Omori, T.; Oreglia, M. J.; Orito, S.; Pálinkás, J.; Pásztor, G.; Pater, J. R.; Patrick, G. N.; Patt, J.; Pearce, M. J.; Petzold, S.; Pfeifenschneider, P.; Pilcher, J. E.; Pinfold, J.; Plane, D. E.; Poffenberger, P.; Poli, B.; Posthaus, A.; Przysiezniak, H.; Rees, D. L.; Rigby, D.; Robertson, S.; Robins, S. A.; Rodning, N.; Roney, J. M.; Rooke, A.; Ros, E.; Rossi, A. M.; Rosvick, M.; Routenburg, P.; Rozen, Y.; Runge, K.; Runolfsson, O.; Ruppel, U.; Rust, D. R.; Rylko, R.; Sachs, K.; Sarkisyan, E. K.G.; Sasaki, M.; Sbarra, C.; Schaile, A. D.; Schaile, O.; Scharf, F.; Scharff-Hansen, P.; Schenk, P.; Schmitt, B.; Schmitt, S.; Schröder, M.; Schultz-Coulon, H. C.; Schulz, M.; Schumacher, M.; Schütz, P.; Scott, W. G.; Shears, T. G.; Shen, B. C.; Shepherd-Themistocleous, C. H.; Sherwood, P.; Siroli, G. P.; Sittler, A.; Skillman, A.; Skuja, A.; Smith, A. M.; Smith, T. J.; Snow, G. A.; Sobie, R.; Söldner-Rembold, S.; Springer, R. W.; Sproston, M.; Stahl, A.; Steiert, M.; Stephens, K.; Steuerer, J.; Stockhausen, B.; Strom, D.; Strumia, F.; Szymanski, P.; Tafirout, R.; Talbot, S. D.; Tanaka, S.; Taras, P.; Tarem, S.; Thiergen, M.; Thomson, M. A.; von Törne, E.; Towers, S.; Trigger, I.; Tsukamoto, T.; Tsur, E.; Turcot, A. S.; Turner-Watson, M. F.; Utzat, P.; van Kooten, R.; Verzocchi, M.; Vikas, P.; Vincter, M.; Vokurka, E. H.; Wäckerle, F.; Wagner, A.; Ward, C. P.; Ward, D. R.; Ward, J. J.; Watkins, P. M.; Watson, A. T.; Watson, N. K.; Wells, P. S.; Wermes, N.; White, J. S.; Wilkens, B.; Wilson, G. W.; Wilson, J. A.; Wolf, G.; Wotton, S.; Wyatt, T. R.; Yamashita, S.; Yekutieli, G.; Zacek, V.

In: Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics, Vol. 391, No. 1-2, 09.01.1997, p. 210-220.

Research output: Contribution to journalArticle

Ackerstaff, K, Alexander, G, Allison, J, Altekamp, N, Ametewee, K, Anderson, KJ, Anderson, S, Arcelli, S, Asai, S, Axen, D, Azuelos, G, Ball, AH, Barberio, E, Barlow, RJ, Bartoldus, R, Batley, JR, Bechtluft, J, Beeston, C, Behnke, T, Bell, AN, Bell, KW, Bella, G, Bentvelsen, S, Berlich, P, Bethke, S, Biebel, O, Blobel, V, Bloodworth, IJ, Bloomer, JE, Bobinski, M, Bock, P, Bosch, HM, Boutemeur, M, Bouwens, BT, Braibant, S, Brown, RM, Buguzzi, A, Burckhart, HJ, Burgard, C, Bürgin, R, Capiluppi, P, Carnegie, RK, Carter, AA, Carter, JR, Chang, CY, Charlton, DG, Chrisman, D, Clarke, PEL, Cohen, I, Conboy, JE, Cooke, OC, Cuffiani, M, Dado, S, Dallapiccola, C, Dallavalle, GM, de Jong, S, del Pozo, LA, Desch, K, Dixit, MS, do Couto e Silva, E, Doucet, M, Duchovni, E, Duckeck, G, Duerdoth, IP, Edwards, JEG, Estabrooks, PG, Evans, HG, Evans, M, Fabbri, F, Fath, P, Fiedler, F, Fierro, M, Fischer, HM, Folman, R, Fong, DG, Foucher, M, Fürtjes, A, Gagnon, P, Gary, JW, Gascon, J, Gascon-Shotkin, SM, Geddes, NI, Geich-Gimbel, C, Geralis, T, Giacomelli, G, Giacomelli, P, Giacomelli, R, Gibson, V, Gibson, WR, Gingrich, DM, Glenzinski, D, Goldberg, J, Goodrick, MJ, Gorn, W, Grandi, C, Gross, E, Grunhaus, J, Gruwé, M, Hajdu, C, Hanson, GG, Hansroul, M, Hapke, M, Hargrove, CK, Hart, PA, Hartmann, C, Hauschild, M, Hawkes, CM, Hawkings, R, Hemingway, RJ, Herndon, M, Herten, G, Heuer, RD, Hildreth, MD, Hill, JC, Hillier, SJ, Hilse, T, Hobson, PR, Homer, RJ, Honma, AK, Horváth, D, Howard, R, Hughes-Jones, RE, Hutchcroft, DE, Igo-Kemenes, P, Imrie, DC, Ingram, MR, Ishii, K, Jawahery, A, Jeffreys, PW, Jeremie, H, Jimack, M, Joly, A, Jones, CR, Jones, G, Jones, M, Jones, RWL, Jost, U, Jovanovic, P, Junk, TR, Karlen, D, Kawagoe, K, Kawamoto, T, Keeler, RK, Kellogg, RG, Kennedy, BW, King, BJ, Kirk, J, Kluth, S, Kobayashi, T, Kobel, M, Koetke, DS, Kokott, TP, Kolrep, M, Komamiya, S, Kress, T, Krieger, P, von Krogh, J, Kyberd, P, Lafferty, GD, Lahmann, R, Lai, WP, Lanske, D, Lauber, J, Lautenschlager, SR, Layter, JG, Lazic, D, Lee, AM, Lefebvre, E, Lellouch, D, Letts, J, Levinson, L, Lewis, C, Lloyd, SL, Loebinger, FK, Long, GD, Losty, MJ, Ludwig, J, Mannelli, M, Marcellini, S, Markus, C, Martin, AJ, Martin, JP, Martinez, G, Mashimo, T, Matthews, W, Mättig, P, McDonald, WJ, McKenna, J, Mckigney, EA, McMahon, TJ, McNab, AI, McPherson, RA, Meijers, F, Menke, S, Merritt, FS, Mes, H, Meyer, J, Michelini, A, Mikenberg, G, Miller, DJ, Mir, R, Mohr, W, Montanari, A, Mori, T, Morii, M, Müller, U, Nagai, K, Nakamura, I, Neal, HA, Nellen, B, Nijjhar, B, Nisius, R, O'Neale, SW, Oakham, FG, Odorici, F, Ogren, HO, Oldershaw, NJ, Omori, T, Oreglia, MJ, Orito, S, Pálinkás, J, Pásztor, G, Pater, JR, Patrick, GN, Patt, J, Pearce, MJ, Petzold, S, Pfeifenschneider, P, Pilcher, JE, Pinfold, J, Plane, DE, Poffenberger, P, Poli, B, Posthaus, A, Przysiezniak, H, Rees, DL, Rigby, D, Robertson, S, Robins, SA, Rodning, N, Roney, JM, Rooke, A, Ros, E, Rossi, AM, Rosvick, M, Routenburg, P, Rozen, Y, Runge, K, Runolfsson, O, Ruppel, U, Rust, DR, Rylko, R, Sachs, K, Sarkisyan, EKG, Sasaki, M, Sbarra, C, Schaile, AD, Schaile, O, Scharf, F, Scharff-Hansen, P, Schenk, P, Schmitt, B, Schmitt, S, Schröder, M, Schultz-Coulon, HC, Schulz, M, Schumacher, M, Schütz, P, Scott, WG, Shears, TG, Shen, BC, Shepherd-Themistocleous, CH, Sherwood, P, Siroli, GP, Sittler, A, Skillman, A, Skuja, A, Smith, AM, Smith, TJ, Snow, GA, Sobie, R, Söldner-Rembold, S, Springer, RW, Sproston, M, Stahl, A, Steiert, M, Stephens, K, Steuerer, J, Stockhausen, B, Strom, D, Strumia, F, Szymanski, P, Tafirout, R, Talbot, SD, Tanaka, S, Taras, P, Tarem, S, Thiergen, M, Thomson, MA, von Törne, E, Towers, S, Trigger, I, Tsukamoto, T, Tsur, E, Turcot, AS, Turner-Watson, MF, Utzat, P, van Kooten, R, Verzocchi, M, Vikas, P, Vincter, M, Vokurka, EH, Wäckerle, F, Wagner, A, Ward, CP, Ward, DR, Ward, JJ, Watkins, PM, Watson, AT, Watson, NK, Wells, PS, Wermes, N, White, JS, Wilkens, B, Wilson, GW, Wilson, JA, Wolf, G, Wotton, S, Wyatt, TR, Yamashita, S, Yekutieli, G & Zacek, V 1997, 'Photonic events with large missing energy in e+e- collisions at √s =161 GeV', Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics, vol. 391, no. 1-2, pp. 210-220. https://doi.org/10.1016/S0370-2693(96)01554-7
Ackerstaff, K. ; Alexander, G. ; Allison, J. ; Altekamp, N. ; Ametewee, K. ; Anderson, K. J. ; Anderson, S. ; Arcelli, S. ; Asai, S. ; Axen, D. ; Azuelos, G. ; Ball, A. H. ; Barberio, E. ; Barlow, R. J. ; Bartoldus, R. ; Batley, J. R. ; Bechtluft, J. ; Beeston, C. ; Behnke, T. ; Bell, A. N. ; Bell, K. W. ; Bella, G. ; Bentvelsen, S. ; Berlich, P. ; Bethke, S. ; Biebel, O. ; Blobel, V. ; Bloodworth, I. J. ; Bloomer, J. E. ; Bobinski, M. ; Bock, P. ; Bosch, H. M. ; Boutemeur, M. ; Bouwens, B. T. ; Braibant, S. ; Brown, R. M. ; Buguzzi, A. ; Burckhart, H. J. ; Burgard, C. ; Bürgin, R. ; Capiluppi, P. ; Carnegie, R. K. ; Carter, A. A. ; Carter, J. R. ; Chang, C. Y. ; Charlton, D. G. ; Chrisman, D. ; Clarke, P. E.L. ; Cohen, I. ; Conboy, J. E. ; Cooke, O. C. ; Cuffiani, M. ; Dado, S. ; Dallapiccola, C. ; Dallavalle, G. M. ; de Jong, S. ; del Pozo, L. A. ; Desch, K. ; Dixit, M. S. ; do Couto e Silva, E. ; Doucet, M. ; Duchovni, E. ; Duckeck, G. ; Duerdoth, I. P. ; Edwards, J. E.G. ; Estabrooks, P. G. ; Evans, H. G. ; Evans, M. ; Fabbri, F. ; Fath, P. ; Fiedler, F. ; Fierro, M. ; Fischer, H. M. ; Folman, R. ; Fong, D. G. ; Foucher, M. ; Fürtjes, A. ; Gagnon, P. ; Gary, J. W. ; Gascon, J. ; Gascon-Shotkin, S. M. ; Geddes, N. I. ; Geich-Gimbel, C. ; Geralis, T. ; Giacomelli, G. ; Giacomelli, P. ; Giacomelli, R. ; Gibson, V. ; Gibson, W. R. ; Gingrich, D. M. ; Glenzinski, D. ; Goldberg, J. ; Goodrick, M. J. ; Gorn, W. ; Grandi, C. ; Gross, E. ; Grunhaus, J. ; Gruwé, M. ; Hajdu, C. ; Hanson, G. G. ; Hansroul, M. ; Hapke, M. ; Hargrove, C. K. ; Hart, P. A. ; Hartmann, C. ; Hauschild, M. ; Hawkes, C. M. ; Hawkings, R. ; Hemingway, R. J. ; Herndon, M. ; Herten, G. ; Heuer, R. D. ; Hildreth, M. D. ; Hill, J. C. ; Hillier, S. J. ; Hilse, T. ; Hobson, P. R. ; Homer, R. J. ; Honma, A. K. ; Horváth, D. ; Howard, R. ; Hughes-Jones, R. E. ; Hutchcroft, D. E. ; Igo-Kemenes, P. ; Imrie, D. C. ; Ingram, M. R. ; Ishii, K. ; Jawahery, A. ; Jeffreys, P. W. ; Jeremie, H. ; Jimack, M. ; Joly, A. ; Jones, C. R. ; Jones, G. ; Jones, M. ; Jones, R. W.L. ; Jost, U. ; Jovanovic, P. ; Junk, T. R. ; Karlen, D. ; Kawagoe, Kiyotomo ; Kawamoto, T. ; Keeler, R. K. ; Kellogg, R. G. ; Kennedy, B. W. ; King, B. J. ; Kirk, J. ; Kluth, S. ; Kobayashi, T. ; Kobel, M. ; Koetke, D. S. ; Kokott, T. P. ; Kolrep, M. ; Komamiya, S. ; Kress, T. ; Krieger, P. ; von Krogh, J. ; Kyberd, P. ; Lafferty, G. D. ; Lahmann, R. ; Lai, W. P. ; Lanske, D. ; Lauber, J. ; Lautenschlager, S. R. ; Layter, J. G. ; Lazic, D. ; Lee, A. M. ; Lefebvre, E. ; Lellouch, D. ; Letts, J. ; Levinson, L. ; Lewis, C. ; Lloyd, S. L. ; Loebinger, F. K. ; Long, G. D. ; Losty, M. J. ; Ludwig, J. ; Mannelli, M. ; Marcellini, S. ; Markus, C. ; Martin, A. J. ; Martin, J. P. ; Martinez, G. ; Mashimo, T. ; Matthews, W. ; Mättig, P. ; McDonald, W. J. ; McKenna, J. ; Mckigney, E. A. ; McMahon, T. J. ; McNab, A. I. ; McPherson, R. A. ; Meijers, F. ; Menke, S. ; Merritt, F. S. ; Mes, H. ; Meyer, J. ; Michelini, A. ; Mikenberg, G. ; Miller, D. J. ; Mir, R. ; Mohr, W. ; Montanari, A. ; Mori, T. ; Morii, M. ; Müller, U. ; Nagai, K. ; Nakamura, I. ; Neal, H. A. ; Nellen, B. ; Nijjhar, B. ; Nisius, R. ; O'Neale, S. W. ; Oakham, F. G. ; Odorici, F. ; Ogren, H. O. ; Oldershaw, N. J. ; Omori, T. ; Oreglia, M. J. ; Orito, S. ; Pálinkás, J. ; Pásztor, G. ; Pater, J. R. ; Patrick, G. N. ; Patt, J. ; Pearce, M. J. ; Petzold, S. ; Pfeifenschneider, P. ; Pilcher, J. E. ; Pinfold, J. ; Plane, D. E. ; Poffenberger, P. ; Poli, B. ; Posthaus, A. ; Przysiezniak, H. ; Rees, D. L. ; Rigby, D. ; Robertson, S. ; Robins, S. A. ; Rodning, N. ; Roney, J. M. ; Rooke, A. ; Ros, E. ; Rossi, A. M. ; Rosvick, M. ; Routenburg, P. ; Rozen, Y. ; Runge, K. ; Runolfsson, O. ; Ruppel, U. ; Rust, D. R. ; Rylko, R. ; Sachs, K. ; Sarkisyan, E. K.G. ; Sasaki, M. ; Sbarra, C. ; Schaile, A. D. ; Schaile, O. ; Scharf, F. ; Scharff-Hansen, P. ; Schenk, P. ; Schmitt, B. ; Schmitt, S. ; Schröder, M. ; Schultz-Coulon, H. C. ; Schulz, M. ; Schumacher, M. ; Schütz, P. ; Scott, W. G. ; Shears, T. G. ; Shen, B. C. ; Shepherd-Themistocleous, C. H. ; Sherwood, P. ; Siroli, G. P. ; Sittler, A. ; Skillman, A. ; Skuja, A. ; Smith, A. M. ; Smith, T. J. ; Snow, G. A. ; Sobie, R. ; Söldner-Rembold, S. ; Springer, R. W. ; Sproston, M. ; Stahl, A. ; Steiert, M. ; Stephens, K. ; Steuerer, J. ; Stockhausen, B. ; Strom, D. ; Strumia, F. ; Szymanski, P. ; Tafirout, R. ; Talbot, S. D. ; Tanaka, S. ; Taras, P. ; Tarem, S. ; Thiergen, M. ; Thomson, M. A. ; von Törne, E. ; Towers, S. ; Trigger, I. ; Tsukamoto, T. ; Tsur, E. ; Turcot, A. S. ; Turner-Watson, M. F. ; Utzat, P. ; van Kooten, R. ; Verzocchi, M. ; Vikas, P. ; Vincter, M. ; Vokurka, E. H. ; Wäckerle, F. ; Wagner, A. ; Ward, C. P. ; Ward, D. R. ; Ward, J. J. ; Watkins, P. M. ; Watson, A. T. ; Watson, N. K. ; Wells, P. S. ; Wermes, N. ; White, J. S. ; Wilkens, B. ; Wilson, G. W. ; Wilson, J. A. ; Wolf, G. ; Wotton, S. ; Wyatt, T. R. ; Yamashita, S. ; Yekutieli, G. ; Zacek, V. / Photonic events with large missing energy in e+e- collisions at √s =161 GeV. In: Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics. 1997 ; Vol. 391, No. 1-2. pp. 210-220.
@article{4b2378fb4c8b4f0abd57e016318173dd,
title = "Photonic events with large missing energy in e+e- collisions at √s =161 GeV",
abstract = "Photonic events with large missing energy have been observed with the OPAL detector at LEP using two search topologies. The first topology looks for events with significant missing energy and at least one photon in |cos θ| < 0.7 with large scaled energy, xy > 0.2. The second topology looks for events with an acoplanar photon pair where both photons are in |cos θ| < 0.7 and have energy exceeding 1.75 GeV. In the data sample corresponding to an integrated luminosity of 10.0 pb-1, 11 events are selected for the first topology and a cross-section of 1.6 ± 0.5 pb is measured within the kinematic acceptance, consistent with that expected for the Standard Model process e+e- → νν̄γ(γ). No events are selected for the second topology giving a 95{\%} CL cross-section upper limit of 0.41 pb within the kinematic acceptance. Upper limits on the cross-section times branching ratio for new particle production are also derived.",
author = "K. Ackerstaff and G. Alexander and J. Allison and N. Altekamp and K. Ametewee and Anderson, {K. J.} and S. Anderson and S. Arcelli and S. Asai and D. Axen and G. Azuelos and Ball, {A. H.} and E. Barberio and Barlow, {R. J.} and R. Bartoldus and Batley, {J. R.} and J. Bechtluft and C. Beeston and T. Behnke and Bell, {A. N.} and Bell, {K. W.} and G. Bella and S. Bentvelsen and P. Berlich and S. Bethke and O. Biebel and V. Blobel and Bloodworth, {I. J.} and Bloomer, {J. E.} and M. Bobinski and P. Bock and Bosch, {H. M.} and M. Boutemeur and Bouwens, {B. T.} and S. Braibant and Brown, {R. M.} and A. Buguzzi and Burckhart, {H. J.} and C. Burgard and R. B{\"u}rgin and P. Capiluppi and Carnegie, {R. K.} and Carter, {A. A.} and Carter, {J. R.} and Chang, {C. Y.} and Charlton, {D. G.} and D. Chrisman and Clarke, {P. E.L.} and I. Cohen and Conboy, {J. E.} and Cooke, {O. C.} and M. Cuffiani and S. Dado and C. Dallapiccola and Dallavalle, {G. M.} and {de Jong}, S. and {del Pozo}, {L. A.} and K. Desch and Dixit, {M. S.} and {do Couto e Silva}, E. and M. Doucet and E. Duchovni and G. Duckeck and Duerdoth, {I. P.} and Edwards, {J. E.G.} and Estabrooks, {P. G.} and Evans, {H. G.} and M. Evans and F. Fabbri and P. Fath and F. Fiedler and M. Fierro and Fischer, {H. M.} and R. Folman and Fong, {D. G.} and M. Foucher and A. F{\"u}rtjes and P. Gagnon and Gary, {J. W.} and J. Gascon and Gascon-Shotkin, {S. M.} and Geddes, {N. I.} and C. Geich-Gimbel and T. Geralis and G. Giacomelli and P. Giacomelli and R. Giacomelli and V. Gibson and Gibson, {W. R.} and Gingrich, {D. M.} and D. Glenzinski and J. Goldberg and Goodrick, {M. J.} and W. Gorn and C. Grandi and E. Gross and J. Grunhaus and M. Gruw{\'e} and C. Hajdu and Hanson, {G. G.} and M. Hansroul and M. Hapke and Hargrove, {C. K.} and Hart, {P. A.} and C. Hartmann and M. Hauschild and Hawkes, {C. M.} and R. Hawkings and Hemingway, {R. J.} and M. Herndon and G. Herten and Heuer, {R. D.} and Hildreth, {M. D.} and Hill, {J. C.} and Hillier, {S. J.} and T. Hilse and Hobson, {P. R.} and Homer, {R. J.} and Honma, {A. K.} and D. Horv{\'a}th and R. Howard and Hughes-Jones, {R. E.} and Hutchcroft, {D. E.} and P. Igo-Kemenes and Imrie, {D. C.} and Ingram, {M. R.} and K. Ishii and A. Jawahery and Jeffreys, {P. W.} and H. Jeremie and M. Jimack and A. Joly and Jones, {C. R.} and G. Jones and M. Jones and Jones, {R. W.L.} and U. Jost and P. Jovanovic and Junk, {T. R.} and D. Karlen and Kiyotomo Kawagoe and T. Kawamoto and Keeler, {R. K.} and Kellogg, {R. G.} and Kennedy, {B. W.} and King, {B. J.} and J. Kirk and S. Kluth and T. Kobayashi and M. Kobel and Koetke, {D. S.} and Kokott, {T. P.} and M. Kolrep and S. Komamiya and T. Kress and P. Krieger and {von Krogh}, J. and P. Kyberd and Lafferty, {G. D.} and R. Lahmann and Lai, {W. P.} and D. Lanske and J. Lauber and Lautenschlager, {S. R.} and Layter, {J. G.} and D. Lazic and Lee, {A. M.} and E. Lefebvre and D. Lellouch and J. Letts and L. Levinson and C. Lewis and Lloyd, {S. L.} and Loebinger, {F. K.} and Long, {G. D.} and Losty, {M. J.} and J. Ludwig and M. Mannelli and S. Marcellini and C. Markus and Martin, {A. J.} and Martin, {J. P.} and G. Martinez and T. Mashimo and W. Matthews and P. M{\"a}ttig and McDonald, {W. J.} and J. McKenna and Mckigney, {E. A.} and McMahon, {T. J.} and McNab, {A. I.} and McPherson, {R. A.} and F. Meijers and S. Menke and Merritt, {F. S.} and H. Mes and J. Meyer and A. Michelini and G. Mikenberg and Miller, {D. J.} and R. Mir and W. Mohr and A. Montanari and T. Mori and M. Morii and U. M{\"u}ller and K. Nagai and I. Nakamura and Neal, {H. A.} and B. Nellen and B. Nijjhar and R. Nisius and O'Neale, {S. W.} and Oakham, {F. G.} and F. Odorici and Ogren, {H. O.} and Oldershaw, {N. J.} and T. Omori and Oreglia, {M. J.} and S. Orito and J. P{\'a}link{\'a}s and G. P{\'a}sztor and Pater, {J. R.} and Patrick, {G. N.} and J. Patt and Pearce, {M. J.} and S. Petzold and P. Pfeifenschneider and Pilcher, {J. E.} and J. Pinfold and Plane, {D. E.} and P. Poffenberger and B. Poli and A. Posthaus and H. Przysiezniak and Rees, {D. L.} and D. Rigby and S. Robertson and Robins, {S. A.} and N. Rodning and Roney, {J. M.} and A. Rooke and E. Ros and Rossi, {A. M.} and M. Rosvick and P. Routenburg and Y. Rozen and K. Runge and O. Runolfsson and U. Ruppel and Rust, {D. R.} and R. Rylko and K. Sachs and Sarkisyan, {E. K.G.} and M. Sasaki and C. Sbarra and Schaile, {A. D.} and O. Schaile and F. Scharf and P. Scharff-Hansen and P. Schenk and B. Schmitt and S. Schmitt and M. Schr{\"o}der and Schultz-Coulon, {H. C.} and M. Schulz and M. Schumacher and P. Sch{\"u}tz and Scott, {W. G.} and Shears, {T. G.} and Shen, {B. C.} and Shepherd-Themistocleous, {C. H.} and P. Sherwood and Siroli, {G. P.} and A. Sittler and A. Skillman and A. Skuja and Smith, {A. M.} and Smith, {T. J.} and Snow, {G. A.} and R. Sobie and S. S{\"o}ldner-Rembold and Springer, {R. W.} and M. Sproston and A. Stahl and M. Steiert and K. Stephens and J. Steuerer and B. Stockhausen and D. Strom and F. Strumia and P. Szymanski and R. Tafirout and Talbot, {S. D.} and S. Tanaka and P. Taras and S. Tarem and M. Thiergen and Thomson, {M. A.} and {von T{\"o}rne}, E. and S. Towers and I. Trigger and T. Tsukamoto and E. Tsur and Turcot, {A. S.} and Turner-Watson, {M. F.} and P. Utzat and {van Kooten}, R. and M. Verzocchi and P. Vikas and M. Vincter and Vokurka, {E. H.} and F. W{\"a}ckerle and A. Wagner and Ward, {C. P.} and Ward, {D. R.} and Ward, {J. J.} and Watkins, {P. M.} and Watson, {A. T.} and Watson, {N. K.} and Wells, {P. S.} and N. Wermes and White, {J. S.} and B. Wilkens and Wilson, {G. W.} and Wilson, {J. A.} and G. Wolf and S. Wotton and Wyatt, {T. R.} and S. Yamashita and G. Yekutieli and V. Zacek",
year = "1997",
month = "1",
day = "9",
doi = "10.1016/S0370-2693(96)01554-7",
language = "English",
volume = "391",
pages = "210--220",
journal = "Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics",
issn = "0370-2693",
publisher = "Elsevier",
number = "1-2",

}

TY - JOUR

T1 - Photonic events with large missing energy in e+e- collisions at √s =161 GeV

AU - Ackerstaff, K.

AU - Alexander, G.

AU - Allison, J.

AU - Altekamp, N.

AU - Ametewee, K.

AU - Anderson, K. J.

AU - Anderson, S.

AU - Arcelli, S.

AU - Asai, S.

AU - Axen, D.

AU - Azuelos, G.

AU - Ball, A. H.

AU - Barberio, E.

AU - Barlow, R. J.

AU - Bartoldus, R.

AU - Batley, J. R.

AU - Bechtluft, J.

AU - Beeston, C.

AU - Behnke, T.

AU - Bell, A. N.

AU - Bell, K. W.

AU - Bella, G.

AU - Bentvelsen, S.

AU - Berlich, P.

AU - Bethke, S.

AU - Biebel, O.

AU - Blobel, V.

AU - Bloodworth, I. J.

AU - Bloomer, J. E.

AU - Bobinski, M.

AU - Bock, P.

AU - Bosch, H. M.

AU - Boutemeur, M.

AU - Bouwens, B. T.

AU - Braibant, S.

AU - Brown, R. M.

AU - Buguzzi, A.

AU - Burckhart, H. J.

AU - Burgard, C.

AU - Bürgin, R.

AU - Capiluppi, P.

AU - Carnegie, R. K.

AU - Carter, A. A.

AU - Carter, J. R.

AU - Chang, C. Y.

AU - Charlton, D. G.

AU - Chrisman, D.

AU - Clarke, P. E.L.

AU - Cohen, I.

AU - Conboy, J. E.

AU - Cooke, O. C.

AU - Cuffiani, M.

AU - Dado, S.

AU - Dallapiccola, C.

AU - Dallavalle, G. M.

AU - de Jong, S.

AU - del Pozo, L. A.

AU - Desch, K.

AU - Dixit, M. S.

AU - do Couto e Silva, E.

AU - Doucet, M.

AU - Duchovni, E.

AU - Duckeck, G.

AU - Duerdoth, I. P.

AU - Edwards, J. E.G.

AU - Estabrooks, P. G.

AU - Evans, H. G.

AU - Evans, M.

AU - Fabbri, F.

AU - Fath, P.

AU - Fiedler, F.

AU - Fierro, M.

AU - Fischer, H. M.

AU - Folman, R.

AU - Fong, D. G.

AU - Foucher, M.

AU - Fürtjes, A.

AU - Gagnon, P.

AU - Gary, J. W.

AU - Gascon, J.

AU - Gascon-Shotkin, S. M.

AU - Geddes, N. I.

AU - Geich-Gimbel, C.

AU - Geralis, T.

AU - Giacomelli, G.

AU - Giacomelli, P.

AU - Giacomelli, R.

AU - Gibson, V.

AU - Gibson, W. R.

AU - Gingrich, D. M.

AU - Glenzinski, D.

AU - Goldberg, J.

AU - Goodrick, M. J.

AU - Gorn, W.

AU - Grandi, C.

AU - Gross, E.

AU - Grunhaus, J.

AU - Gruwé, M.

AU - Hajdu, C.

AU - Hanson, G. G.

AU - Hansroul, M.

AU - Hapke, M.

AU - Hargrove, C. K.

AU - Hart, P. A.

AU - Hartmann, C.

AU - Hauschild, M.

AU - Hawkes, C. M.

AU - Hawkings, R.

AU - Hemingway, R. J.

AU - Herndon, M.

AU - Herten, G.

AU - Heuer, R. D.

AU - Hildreth, M. D.

AU - Hill, J. C.

AU - Hillier, S. J.

AU - Hilse, T.

AU - Hobson, P. R.

AU - Homer, R. J.

AU - Honma, A. K.

AU - Horváth, D.

AU - Howard, R.

AU - Hughes-Jones, R. E.

AU - Hutchcroft, D. E.

AU - Igo-Kemenes, P.

AU - Imrie, D. C.

AU - Ingram, M. R.

AU - Ishii, K.

AU - Jawahery, A.

AU - Jeffreys, P. W.

AU - Jeremie, H.

AU - Jimack, M.

AU - Joly, A.

AU - Jones, C. R.

AU - Jones, G.

AU - Jones, M.

AU - Jones, R. W.L.

AU - Jost, U.

AU - Jovanovic, P.

AU - Junk, T. R.

AU - Karlen, D.

AU - Kawagoe, Kiyotomo

AU - Kawamoto, T.

AU - Keeler, R. K.

AU - Kellogg, R. G.

AU - Kennedy, B. W.

AU - King, B. J.

AU - Kirk, J.

AU - Kluth, S.

AU - Kobayashi, T.

AU - Kobel, M.

AU - Koetke, D. S.

AU - Kokott, T. P.

AU - Kolrep, M.

AU - Komamiya, S.

AU - Kress, T.

AU - Krieger, P.

AU - von Krogh, J.

AU - Kyberd, P.

AU - Lafferty, G. D.

AU - Lahmann, R.

AU - Lai, W. P.

AU - Lanske, D.

AU - Lauber, J.

AU - Lautenschlager, S. R.

AU - Layter, J. G.

AU - Lazic, D.

AU - Lee, A. M.

AU - Lefebvre, E.

AU - Lellouch, D.

AU - Letts, J.

AU - Levinson, L.

AU - Lewis, C.

AU - Lloyd, S. L.

AU - Loebinger, F. K.

AU - Long, G. D.

AU - Losty, M. J.

AU - Ludwig, J.

AU - Mannelli, M.

AU - Marcellini, S.

AU - Markus, C.

AU - Martin, A. J.

AU - Martin, J. P.

AU - Martinez, G.

AU - Mashimo, T.

AU - Matthews, W.

AU - Mättig, P.

AU - McDonald, W. J.

AU - McKenna, J.

AU - Mckigney, E. A.

AU - McMahon, T. J.

AU - McNab, A. I.

AU - McPherson, R. A.

AU - Meijers, F.

AU - Menke, S.

AU - Merritt, F. S.

AU - Mes, H.

AU - Meyer, J.

AU - Michelini, A.

AU - Mikenberg, G.

AU - Miller, D. J.

AU - Mir, R.

AU - Mohr, W.

AU - Montanari, A.

AU - Mori, T.

AU - Morii, M.

AU - Müller, U.

AU - Nagai, K.

AU - Nakamura, I.

AU - Neal, H. A.

AU - Nellen, B.

AU - Nijjhar, B.

AU - Nisius, R.

AU - O'Neale, S. W.

AU - Oakham, F. G.

AU - Odorici, F.

AU - Ogren, H. O.

AU - Oldershaw, N. J.

AU - Omori, T.

AU - Oreglia, M. J.

AU - Orito, S.

AU - Pálinkás, J.

AU - Pásztor, G.

AU - Pater, J. R.

AU - Patrick, G. N.

AU - Patt, J.

AU - Pearce, M. J.

AU - Petzold, S.

AU - Pfeifenschneider, P.

AU - Pilcher, J. E.

AU - Pinfold, J.

AU - Plane, D. E.

AU - Poffenberger, P.

AU - Poli, B.

AU - Posthaus, A.

AU - Przysiezniak, H.

AU - Rees, D. L.

AU - Rigby, D.

AU - Robertson, S.

AU - Robins, S. A.

AU - Rodning, N.

AU - Roney, J. M.

AU - Rooke, A.

AU - Ros, E.

AU - Rossi, A. M.

AU - Rosvick, M.

AU - Routenburg, P.

AU - Rozen, Y.

AU - Runge, K.

AU - Runolfsson, O.

AU - Ruppel, U.

AU - Rust, D. R.

AU - Rylko, R.

AU - Sachs, K.

AU - Sarkisyan, E. K.G.

AU - Sasaki, M.

AU - Sbarra, C.

AU - Schaile, A. D.

AU - Schaile, O.

AU - Scharf, F.

AU - Scharff-Hansen, P.

AU - Schenk, P.

AU - Schmitt, B.

AU - Schmitt, S.

AU - Schröder, M.

AU - Schultz-Coulon, H. C.

AU - Schulz, M.

AU - Schumacher, M.

AU - Schütz, P.

AU - Scott, W. G.

AU - Shears, T. G.

AU - Shen, B. C.

AU - Shepherd-Themistocleous, C. H.

AU - Sherwood, P.

AU - Siroli, G. P.

AU - Sittler, A.

AU - Skillman, A.

AU - Skuja, A.

AU - Smith, A. M.

AU - Smith, T. J.

AU - Snow, G. A.

AU - Sobie, R.

AU - Söldner-Rembold, S.

AU - Springer, R. W.

AU - Sproston, M.

AU - Stahl, A.

AU - Steiert, M.

AU - Stephens, K.

AU - Steuerer, J.

AU - Stockhausen, B.

AU - Strom, D.

AU - Strumia, F.

AU - Szymanski, P.

AU - Tafirout, R.

AU - Talbot, S. D.

AU - Tanaka, S.

AU - Taras, P.

AU - Tarem, S.

AU - Thiergen, M.

AU - Thomson, M. A.

AU - von Törne, E.

AU - Towers, S.

AU - Trigger, I.

AU - Tsukamoto, T.

AU - Tsur, E.

AU - Turcot, A. S.

AU - Turner-Watson, M. F.

AU - Utzat, P.

AU - van Kooten, R.

AU - Verzocchi, M.

AU - Vikas, P.

AU - Vincter, M.

AU - Vokurka, E. H.

AU - Wäckerle, F.

AU - Wagner, A.

AU - Ward, C. P.

AU - Ward, D. R.

AU - Ward, J. J.

AU - Watkins, P. M.

AU - Watson, A. T.

AU - Watson, N. K.

AU - Wells, P. S.

AU - Wermes, N.

AU - White, J. S.

AU - Wilkens, B.

AU - Wilson, G. W.

AU - Wilson, J. A.

AU - Wolf, G.

AU - Wotton, S.

AU - Wyatt, T. R.

AU - Yamashita, S.

AU - Yekutieli, G.

AU - Zacek, V.

PY - 1997/1/9

Y1 - 1997/1/9

N2 - Photonic events with large missing energy have been observed with the OPAL detector at LEP using two search topologies. The first topology looks for events with significant missing energy and at least one photon in |cos θ| < 0.7 with large scaled energy, xy > 0.2. The second topology looks for events with an acoplanar photon pair where both photons are in |cos θ| < 0.7 and have energy exceeding 1.75 GeV. In the data sample corresponding to an integrated luminosity of 10.0 pb-1, 11 events are selected for the first topology and a cross-section of 1.6 ± 0.5 pb is measured within the kinematic acceptance, consistent with that expected for the Standard Model process e+e- → νν̄γ(γ). No events are selected for the second topology giving a 95% CL cross-section upper limit of 0.41 pb within the kinematic acceptance. Upper limits on the cross-section times branching ratio for new particle production are also derived.

AB - Photonic events with large missing energy have been observed with the OPAL detector at LEP using two search topologies. The first topology looks for events with significant missing energy and at least one photon in |cos θ| < 0.7 with large scaled energy, xy > 0.2. The second topology looks for events with an acoplanar photon pair where both photons are in |cos θ| < 0.7 and have energy exceeding 1.75 GeV. In the data sample corresponding to an integrated luminosity of 10.0 pb-1, 11 events are selected for the first topology and a cross-section of 1.6 ± 0.5 pb is measured within the kinematic acceptance, consistent with that expected for the Standard Model process e+e- → νν̄γ(γ). No events are selected for the second topology giving a 95% CL cross-section upper limit of 0.41 pb within the kinematic acceptance. Upper limits on the cross-section times branching ratio for new particle production are also derived.

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U2 - 10.1016/S0370-2693(96)01554-7

DO - 10.1016/S0370-2693(96)01554-7

M3 - Article

VL - 391

SP - 210

EP - 220

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 - 1-2

ER -