Search for scalar top and scalar bottom quarks at root s = 183 GeV at LEP

Authors
Ackerstaff, K Alexander, G Allison, J Altekamp, N Anderson, KJ Anderson, S Arcelli, S Asai, S Axen, D Azuelos, G Ball, AH Barberio, E Barlow, RJ Bartoldus, R Batley, JR Baumann, S Bechtluft, J Beeston, C Behnke, T Bell, AN Bell, KW Bella, G Bentvelsen, S Bethke, S Biebel, O Biguzzi, A Bird, SD Blobel, V Bloodworth, IJ Bloomer, JE Bobinski, M Bock, P Bonacorsi, D Boutemeur, M Bouwens, BT Braibant, S Brigliadori, L Brown, RM Burckhart, HJ Burgard, C Burgin, 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 Davis, R De Jong, S del Pozo, LA Desch, K Dienes, B Dixit, MS Silva, EDE Doucet, M Duchovni, E Duckeck, G Duerdoth, IP Eatough, D Edwards, JEG Estabrooks, PG Evans, HG Evans, M Fabbri, F Fanti, M Faust, AA Fiedler, F Fierro, M Fischer, HM Fleck, I Folman, R Fong, DG Foucher, M Furtjes, A Futyan, DI 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 Gruwe, 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 Hobson, PR Homer, RJ Honma, AK Horvath, D Hossain, KR Howard, R Huntemeyer, P 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 Jost, U Jovanovic, P Junk, TR Karlen, D Kartvelishvili, V Kawagoe, K Kawamoto, T Kayal, PI Keeler, RK Kellogg, RG Kennedy, BW Kirk, J Klier, A 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 Lloyd, SL Loebinger, FK Long, GD Losty, MJ Ludwig, J Macchiolo, A Macpherson, A Mannelli, M Marcellini, S Markus, C Martin, AJ Martin, JP Martinez, G Mashimo, T Mattig, P McDonald, WJ McKenna, J McKigney, EA McMahon, TJ McPherson, RA Meijers, F Menke, S Merritt, FS Mes, H Meyer, J Michelini, A Mikenberg, G Miller, DJ Mincer, A Mir, R Mohr, W Montanari, A Mori, T Morii, M Muller, U Mihara, S Nagai, K Nakamura, I Neal, HA Nellen, B Nisius, R O'Neale, SW Oakham, FG Odorici, F Ogren, HO Oh, A Oldershaw, NJ Oreglia, MJ Orito, S Palinkas, J Pasztor, G Pater, JR Patrick, GN Patt, J Pearce, MJ Perez-Ochoa, R Petzold, S Pfeifenschneider, P Pilcher, JE Pinfold, J Plane, DE Poffenberger, P Poli, B Posthaus, A Rees, DL Rigby, D Robertson, S Robins, SA Rodning, N Roney, JM Rooke, A Ros, E Rossi, AM Routenburg, P Rozen, Y Runge, K Runolfsson, O Ruppel, U Rust, DR Rylko, R Sachs, K Saeki, T Sarkisyan, EKG Sbarra, C Schaile, AD Schaile, O Scharf, F Scharff-Hansen, P Schenk, P Schieck, J Schleper, P Schmitt, B Schmitt, S Schoning, A Schroder, M Schultz-Coulon, HC Schumacher, M Schwick, C Scott, WG Shears, TG Shen, BC Shepherd-Themistocleous, CH Sherwood, P Siroli, GP Sittler, A Skillman, A Skuja, A Smith, AM Snow, GA Sobie, R Soldner-Rembold, S Springer, RW Sproston, M Stephens, K Steuerer, J Stockhausen, B Stoll, K Strom, D Szymanski, P Tafirout, R Talbot, SD Tanaka, S Taras, P Tarem, S Teuscher, R Thiergen, M Thomson, MA von Torne, E Towers, S Trigger, I Trocsanyi, Z Tsur, E Turcot, AS Turner-Watson, MF Utzat, P Van Kooten, R Verzocchi, M Vikas, P Vokurka, EH Voss, H Wackerle, F Wagner, A Ward, CP Ward, DR Watkins, PM Watson, AT Watson, NK Wells, PS Wermes, N White, JS Wilkens, B Wilson, GW Wilson, JA Wolf, G Wyatt, TR Yamashita, S Yekutieli, G Zacek, V Zer-Zion, D
Citation
K. Ackerstaff et al., Search for scalar top and scalar bottom quarks at root s = 183 GeV at LEP, EUR PHY J C, 6(2), 1999, pp. 225-238
Citations number
52
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Physics
Journal title
EUROPEAN PHYSICAL JOURNAL C
ISSN journal
1434-6044 → ACNP
Volume
6
Issue
2
Year of publication
1999
Pages
225 - 238
Database
ISI
SICI code
1434-6044(199901)6:2<225:SFSTAS>2.0.ZU;2-6
Abstract
Searches for a scalar top quark and a scalar bottom quark have been perform ed using a total data sample of 56.8 pb(-1) at a centre-of-mass energy of r oot s = 183 GeV collected with the OPAL detector at LEP. No candidate event s were observed. Combining this result with those obtained at lower centre- of-mass energies, the 95% C.L. lower limit on the scalar top quark mass is 85.0 GeV if the mixing angle between the supersymmetric partners of the lef t- and right-handed states of the top quark is zero. The lower limit is 81. 3 GeV, even if the scalar top quark decouples from the Z(0) boson. These li mits were obtained assuming that the scalar top quark decays into a charm q uark and the lightest neutralino, and that the mass difference between the scalar top quark and the lightest neutralino is larger than 10 GeV. The com plementary decay mode of the scalar top quark in which it decays into a bot tom quark, a charged lepton and a scalar neutrino was also studied. From a similar analysis, a mass limit on the light scalar bottom quark was set at 82.7 GeV for a mass difference between the scalar bottom quark and the ligh test neutralino larger than 7 GeV, and at 84.0 GeV for the mass difference larger 10 GeV and the lightest neutralino heavier than 30 GeV. These limits were obtained assuming that the scalar bottom quark decays into a bottom q uark and the lightest neutralino, and that a mixing angle between the super symmetric partners of the left- and right-handed states of the bottom quark is zero.