Limits on anomalous WWg and WWZ couplings from WWÕWZ\en j j production B. Abbott, M. Abolins, V. Abramov, B. S. Acharya, 13 D. L. Adams, 54 M. Adams, 30 S. Ahn, V. Akimov, G. A. Alves, N. Amos, E. W. Anderson, 36 M. M. Baarmand, 49 V. V. Babintsev, 19 L. Babukhadia, 49 A. Baden, 40 B. Baldin, S. Banerjee, 13 J. Bantly, 53 E. Barberis, 22 P. Baringer, 37 J. F. Bartlett, 29 U. Bassler, 9 A. Belyaev, 18 S. B. Beri, G. Bernardi, 9 I. Bertram, 20 V. A. Bezzubov, 19 P. C. Bhat, 29 V. Bhatnagar, 11 M. Bhattacharjee, 49 G. Blazey, 31 S. Blessing, 27

B. Abbott, M. Abolins, V. Abramov, B.S. Acharya, I. Adam, D.L. Adams, M. Adams, S. Ahn, H. Aihara, G.A. Alves, N. Amos, E.W. Anderson, R. Astur, M.M. Baarmand, V.V. Babintsev, L. Babukhadia, A. Baden, V. Balamurali, B. Baldin, S. Banerjee, J. Bantly, E. Barberis, P. Baringer, J.F. Bartlett, A. Belyaev, S.B. Beri, I. Bertram, V.A. Bezzubov, P.C. Bhat, V. Bhatnagar, M. Bhattacharjee, N. Biswas, G. Blazey, S. Blessing, P. Bloom, A. Boehnlein, N.I. Bojko, F. Borcherding, C. Boswell, A. Brandt, R. Breedon, R. Brock, A. Bross, D. Buchholz, V.S. Burtovoi, J.M. Butler, W. Carvalho, D. Casey, Z. Casilum, H. Castilla-Valdez, D. Chakraborty, S.-M. Chang, S.V. Chekulaev, L.-P. Chen, W. Chen, S. Choi, S. Chopra, B.C. Choudhary, J.H. Christenson, M. Chung, D. Claes, A.R. Clark, W.G. Cobau, J. Cochran, L. Coney, W.E. Cooper, C. Cretsinger, D. Cullen-Vidal, M.A.C. Cummings, D. Cutts, O.I. Dahl, K. Davis, K. De, K. Del Signore, M. Demarteau, D. Denisov, S.P. Denisov, H.T. Diehl, M. Diesburg, G. Di Loreto, P. Draper, Y. Ducros, L.V. Dudko, S.R. Dugad, A. Dyshkant, D. Edmunds, J. Ellison, V.D. Elvira, R. Engelmann, S. Eno, G. Eppley, P. Ermolov, O.V. Eroshin, V.N. Evdokimov, T. Fahland, M.K. Fatyga, S. Feher, D. Fein, T. Ferbel, G. Finocchiaro, H.E. Fisk, Y. Fisyak, E. Flattum, G.E. Forden, M. Fortner, K.C. Frame, S. Fuess, E. Gallas, A.N. Galyaev, P. Gartung, V. Gavrilov, T.L. Geld, R.J. Genik II, K. Genser, C.E. Gerber, Y. Gershtein, B. Gibbard, B. Gobbi, B. Gómez, G. Gómez, P.I. Goncharov, J.L. González Soĺıs, H. Gordon, L.T. Goss, K. Gounder, A. Goussiou, N. Graf, P.D. Grannis, D.R. Green, H. Greenlee, S. Grinstein, P. Grudberg, S. Grünendahl, G. Guglielmo, J.A. Guida, J.M. Guida, A. Gupta, S.N. Gurzhiev, G. Gutierrez, P. Gutierrez, N.J. Hadley, H. Haggerty, S. Hagopian, V. Hagopian, K.S. Hahn, R.E. Hall, P. Hanlet, S. Hansen, J.M. Hauptman, D. Hedin, A.P. Heinson, U. Heintz, R. Hernández-Montoya, T. Heuring, R. Hirosky, J.D. Hobbs, B. Hoeneisen, J.S. Hoftun, F. Hsieh, Ting Hu, Tong Hu, T. Huehn, A.S. Ito, E. James, J. Jaques, S.A. Jerger, R. Jesik, T. Joffe-Minor, K. Johns, M. Johnson, A. Jonckheere, M. Jones, H. Jöstlein, S.Y. Jun, C.K. Jung, S. Kahn, G. Kalbfleisch, D. Karmanov, D. Karmgard, R. Kehoe, M.L. Kelly, S.K. Kim, B. Klima, C. Klopfenstein, W. Ko, J.M. Kohli, D. Koltick, A.V. Kostritskiy, J. Kotcher, A.V. Kotwal, A.V. Kozelov, E.A. Kozlovsky, J. Krane, M.R. Krishnaswamy, S. Krzywdzinski, S. Kuleshov, S. Kunori, F. Landry, G. Landsberg, B. Lauer, A. Leflat, J. Li, Q.Z. Li-Demarteau, J.G.R. Lima, D. Lincoln, S.L. Linn, J. Linnemann, R. Lipton, F. Lobkowicz, S.C. Loken, A. Lucotte, L. Lueking, A.L. Lyon, A.K.A. Maciel, R.J. Madaras, R. Madden, L. Magaña-Mendoza, V. Manankov, S. Mani, H.S. Mao, R. Markeloff, T. Marshall, M.I. Martin, K.M. Mauritz, B. May, A.A. Mayorov, R. McCarthy, J. McDonald, T. McKibben, J. McKinley, T. McMahon, H.L. Melanson, M. Merkin, K.W. Merritt, C. Miao, H. Miettinen, A. Mincer, C.S. Mishra, N. Mokhov, N.K. Mondal, H.E. Montgomery, P. Mooney, M. Mostafa, H. da Motta, C. Murphy, F. Nang, M. Narain, V.S. Narasimham, A. Narayanan, H.A. Neal, J.P. Negret, P. Nemethy, D. Norman, L. Oesch, V. Oguri, E. Oliveira, E. Oltman, N. Oshima, D. Owen, P. Padley, A. Para, Y.M. Park, R. Partridge, N. Parua, M. Paterno, B. Pawlik, J. Perkins, M. Peters, R. Piegaia, H. Piekarz, Y. Pischalnikov, B.G. Pope, H.B. Prosper, S. Protopopescu, J. Qian, P.Z. Quintas, R. Raja, S. Rajagopalan, O. Ramirez, S. Reucroft, M. Rijssenbeek, T. Rockwell, M. Roco, P. Rubinov, R. Ruchti, J. Rutherfoord, A. Sánchez-Hernández, A. Santoro, L. Sawyer, R.D. Schamberger, H. Schellman, J. Sculli, E. Shabalina, C. Shaffer, H.C. Shankar, R.K. Shivpuri, M. Shupe, H. Singh, J.B. Singh, V. Sirotenko, E. Smith, R.P. Smith, R. Snihur, G.R. Snow, J. Snow, S. Snyder, J. Solomon, M. Sosebee, N. Sotnikova, M. Souza, A.L. Spadafora, G. Steinbrück, R.W. Stephens, M.L. Stevenson, D. Stewart, F. Stichelbaut, D. Stoker, V. Stolin, D.A. Stoyanova, M. Strauss, K. Streets, M. Strovink, A. Sznajder, P. Tamburello, J. Tarazi, M. Tartaglia, T.L.T. Thomas, J. Thompson, T.G. Trippe, P.M. Tuts, V. Vaniev, N. Varelas, E.W. Varnes, D. Vititoe, A.A. Volkov, A.P. Vorobiev, H.D. Wahl, G. Wang, J. Warchol, G. Watts, M. Wayne, H. Weerts, A. White, J.T. White, J.A. Wightman, S. Willis, S.J. Wimpenny, J.V.D. Wirjawan, J. Womersley, E. Won, D.R. Wood, Z. Wu, H. Xu, R. Yamada, P. Yamin, T. Yasuda, P. Yepes, K. Yip, C. Yoshikawa, S. Youssef, J. Yu, Y. Yu, B. Zhang, Y. Zhou, Z. Zhou, Z.H. Zhu, M. Zielinski, D. Zieminska, A. Zieminski, E.G. Zverev, and A. Zylberstejn

B. Abbott, M. Abolins, B.S. Acharya, I. Adam, D.L. Adams, M. Adams, S. Ahn, H. Aihara, G.A. Alves, N. Amos, E.W. Anderson, R. Astur, M.M. Baarmand, A. Baden, V. Balamurali, J. Balderston, B. Baldin, S. Banerjee, J. Bantly, E. Barberis, J.F. Bartlett, K. Bazizi, A. Belyaev, S.B. Beri, I. Bertram, V.A. Bezzubov, P.C. Bhat, V. Bhatnagar, M. Bhattacharjee, N. Biswas, G. Blazey, S. Blessing, P. Bloom, A. Boehnlein, N.I. Bojko, F. Borcherding, C. Boswell, A. Brandt, R. Brock, A. Bross, D. Buchholz, V.S. Burtovoi, J.M. Butler, W. Carvalho, D. Casey, Z. Casilum, H. Castilla-Valdez, D. Chakraborty, S.-M. Chang, S.V. Chekulaev, L.-P. Chen, W. Chen, S. Choi, S. Chopra, B.C. Choudhary, J.H. Christenson, M. Chung, D. Claes, A.R. Clark, W.G. Cobau, J. Cochran, L. Coney, W.E. Cooper, C. Cretsinger, D. Cullen-Vidal, M.A.C. Cummings, D. Cutts, O.I. Dahl, K. Davis, K. De, K. Del Signore, M. Demarteau, D. Denisov, S.P. Denisov, H.T. Diehl, M. Diesburg, G. Di Loreto, P. Draper, Y. Ducros, L.V. Dudko, S.R. Dugad, D. Edmunds, J. Ellison, V.D. Elvira, R. Engelmann, S. Eno, G. Eppley, P. Ermolov, O.V. Eroshin, V.N. Evdokimov, T. Fahland, M.K. Fatyga, S. Feher, D. Fein, T. Ferbel, G. Finocchiaro, H.E. Fisk, Y. Fisyak, E. Flattum, G.E. Forden, M. Fortner, K.C. Frame, S. Fuess, E. Gallas, A.N. Galyaev, P. Gartung, T.L. Geld, R.J. Genik II, K. Genser, C.E. Gerber, B. Gibbard, S. Glenn, B. Gobbi, A. Goldschmidt, B. Gómez, G. Gómez, P.I. Goncharov, J.L. González Soĺıs, H. Gordon, L.T. Goss, K. Gounder, A. Goussiou, N. Graf, P.D. Grannis, D.R. Green, H. Greenlee, G. Grim, S. Grinstein, N. Grossman, P. Grudberg, S. Grünendahl, G. Guglielmo, J.A. Guida, J.M. Guida, A. Gupta, S.N. Gurzhiev, P. Gutierrez, Y.E. Gutnikov, N.J. Hadley, H. Haggerty, S. Hagopian, V. Hagopian, K.S. Hahn, R.E. Hall, P. Hanlet, S. Hansen, J.M. Hauptman, D. Hedin, A.P. Heinson, U. Heintz, R. Hernández-Montoya, T. Heuring, R. Hirosky, J.D. Hobbs, B. Hoeneisen, J.S. Hoftun, F. Hsieh, Ting Hu, Tong Hu, T. Huehn, A.S. Ito, E. James, J. Jaques, S.A. Jerger, R. Jesik, J.Z.-Y. Jiang, T. Joffe-Minor, K. Johns, M. Johnson, A. Jonckheere, M. Jones, H. Jöstlein, S.Y. Jun, C.K. Jung, S. Kahn, G. Kalbfleisch, J.S. Kang, D. Karmanov, D. Karmgard, R. Kehoe, M.L. Kelly, C.L. Kim, S.K. Kim, A. Klatchko, B. Klima, C. Klopfenstein, V.I. Klyukhin, V.I. Kochetkov, J.M. Kohli, D. Koltick, A.V. Kostritskiy, J. Kotcher, A.V. Kotwal, J. Kourlas, A.V. Kozelov, E.A. Kozlovski, J. Krane, M.R. Krishnaswamy, S. Krzywdzinski, S. Kunori, S. Lami, R. Lander, F. Landry, G. Landsberg, B. Lauer, A. Leflat, H. Li, J. Li, Q.Z. Li-Demarteau, J.G.R. Lima, D. Lincoln, S.L. Linn, J. Linnemann, R. Lipton, Y.C. Liu, F. Lobkowicz, S.C. Loken, S. Lökös, L. Lueking, A.L. Lyon, A.K.A. Maciel, R.J. Madaras, R. Madden, L. Magaña-Mendoza, V. Manankov, S. Mani, H.S. Mao, R. Markeloff, T. Marshall, M.I. Martin, K.M. Mauritz, B. May, A.A. Mayorov, R. McCarthy, J. McDonald, T. McKibben, J. McKinley, T. McMahon, H.L. Melanson, M. Merkin, K.W. Merritt, H. Miettinen, A. Mincer, C.S. Mishra, N. Mokhov, N.K. Mondal, H.E. Montgomery, P. Mooney, H. da Motta, C. Murphy, F. Nang, M. Narain, V.S. Narasimham, A. Narayanan, H.A. Neal, J.P. Negret, P. Nemethy, D. Norman, L. Oesch, V. Oguri, E. Oliveira, E. Oltman, N. Oshima, D. Owen, P. Padley, A. Para, Y.M. Park, R. Partridge, N. Parua, M. Paterno, B. Pawlik, J. Perkins, M. Peters, R. Piegaia, H. Piekarz, Y. Pischalnikov, V.M. Podstavkov, B.G. Pope, H.B. Prosper, S. Protopopescu, J. Qian, P.Z. Quintas, R. Raja, S. Rajagopalan, O. Ramirez, L. Rasmussen, S. Reucroft, M. Rijssenbeek, T. Rockwell, M. Roco, N.A. Roe, P. Rubinov, R. Ruchti, J. Rutherfoord, A. Sánchez-Hernández, A. Santoro, L. Sawyer, R.D. Schamberger, H. Schellman, J. Sculli, E. Shabalina, C. Shaffer, H.C. Shankar, R.K. Shivpuri, M. Shupe, H. Singh, J.B. Singh, V. Sirotenko, W. Smart, E. Smith, R.P. Smith, R. Snihur, G.R. Snow, J. Snow, S. Snyder, J. Solomon, P.M. Sood, M. Sosebee, N. Sotnikova, M. Souza, A.L. Spadafora, G. Steinbrück, R.W. Stephens, M.L. Stevenson, D. Stewart, F. Stichelbaut, D.A. Stoianova, D. Stoker, M. Strauss, K. Streets, M. Strovink, A. Sznajder, P. Tamburello, J. Tarazi, M. Tartaglia, T.L.T. Thomas, J. Thompson, T.G. Trippe, P.M. Tuts, N. Varelas, E.W. Varnes, D. Vititoe, A.A. Volkov, A.P. Vorobiev, H.D. Wahl, G. Wang, J. Warchol, G. Watts, M. Wayne, H. Weerts, A. White, J.T. White, J.A. Wightman, S. Willis, S.J. Wimpenny, J.V.D. Wirjawan, J. Womersley, E. Won, D.R. Wood, H. Xu, R. Yamada, P. Yamin, J. Yang, T. Yasuda, P. Yepes, C. Yoshikawa, S. Youssef, J. Yu, Y. Yu, Z.H. Zhu, D. Zieminska, A. Zieminski, E.G. Zverev, and A. Zylberstejn

B. Abbott, M. Abolins, V. Abramov, B.S. Acharya, I. Adam, D.L. Adams, M. Adams, S. Ahn, V. Akimov, G.A. Alves, N. Amos, E.W. Anderson, M.M. Baarmand, V.V. Babintsev, L. Babukhadia, A. Baden, B. Baldin, S. Banerjee, J. Bantly, E. Barberis, P. Baringer, J.F. Bartlett, A. Belyaev, S.B. Beri, I. Bertram, V.A. Bezzubov, P.C. Bhat, V. Bhatnagar, M. Bhattacharjee, N. Biswas, G. Blazey, S. Blessing, P. Bloom, A. Boehnlein, N.I. Bojko, F. Borcherding, C. Boswell, A. Brandt, R. Breedon, G. Briskin, R. Brock, A. Bross, D. Buchholz, V.S. Burtovoi, J.M. Butler, W. Carvalho, D. Casey, Z. Casilum, H. Castilla-Valdez, D. Chakraborty, S.V. Chekulaev, W. Chen, S. Choi, S. Chopra, B.C. Choudhary, J.H. Christenson, M. Chung, D. Claes, A.R. Clark, W.G. Cobau, J. Cochran, L. Coney, W.E. Cooper, D. Coppage, C. Cretsinger, D. Cullen-Vidal, M.A.C. Cummings, D. Cutts, O.I. Dahl, K. Davis, K. De, K. Del Signore, M. Demarteau, D. Denisov, S.P. Denisov, H.T. Diehl, M. Diesburg, G. Di Loreto, P. Draper, Y. Ducros, L.V. Dudko, S.R. Dugad, A. Dyshkant, D. Edmunds, J. Ellison, V.D. Elvira, R. Engelmann, S. Eno, G. Eppley, P. Ermolov, O.V. Eroshin, H. Evans, V.N. Evdokimov, T. Fahland, M.K. Fatyga, S. Feher, D. Fein, T. Ferbel, H.E. Fisk, Y. Fisyak, E. Flattum, G.E. Forden, M. Fortner, K.C. Frame, S. Fuess, E. Gallas, A.N. Galyaev, P. Gartung, V. Gavrilov, T.L. Geld, R.J. Genik II, K. Genser, C.E. Gerber, Y. Gershtein, B. Gibbard, B. Gobbi, B. Gómez, G. Gómez, P.I. Goncharov, J.L. González Soĺıs, H. Gordon, L.T. Goss, K. Gounder, A. Goussiou, N. Graf, P.D. Grannis, D.R. Green, J.A. Green, H. Greenlee, S. Grinstein, P. Grudberg, S. Grünendahl, G. Guglielmo, J.A. Guida, J.M. Guida, A. Gupta, S.N. Gurzhiev, G. Gutierrez, P. Gutierrez, N.J. Hadley, H. Haggerty, S. Hagopian, V. Hagopian, K.S. Hahn, R.E. Hall, P. Hanlet, S. Hansen, J.M. Hauptman, C. Hays, C. Hebert, D. Hedin, A.P. Heinson, U. Heintz, R. Hernández-Montoya, T. Heuring, R. Hirosky, J.D. Hobbs, B. Hoeneisen, J.S. Hoftun, F. Hsieh, Tong Hu, A.S. Ito, S.A. Jerger, R. Jesik, T. Joffe-Minor, K. Johns, M. Johnson, A. Jonckheere, M. Jones, H. Jöstlein, S.Y. Jun, C.K. Jung, S. Kahn, D. Karmanov, D. Karmgard, R. Kehoe, S.K. Kim, B. Klima, C. Klopfenstein, B. Knuteson, W. Ko, J.M. Kohli, D. Koltick, A.V. Kostritskiy, J. Kotcher, A.V. Kotwal, A.V. Kozelov, E.A. Kozlovsky, J. Krane, M.R. Krishnaswamy, S. Krzywdzinski, M. Kubantsev, S. Kuleshov, Y. Kulik, S. Kunori, F. Landry, G. Landsberg, A. Leflat, J. Li, Q.Z. Li, J.G.R. Lima, D. Lincoln, S.L. Linn, J. Linnemann, R. Lipton, A. Lucotte, L. Lueking, A.L. Lyon, A.K.A. Maciel, R.J. Madaras, R. Madden, L. Magaña-Mendoza, V. Manankov, S. Mani, H.S. Mao, R. Markeloff, T. Marshall, M.I. Martin, R.D. Martin, K.M. Mauritz, B. May, A.A. Mayorov, R. McCarthy, J. McDonald, T. McKibben, J. McKinley, T. McMahon, H.L. Melanson, M. Merkin, K.W. Merritt, C. Miao, H. Miettinen, A. Mincer, C.S. Mishra, N. Mokhov, N.K. Mondal, H.E. Montgomery, P. Mooney, M. Mostafa, H. da Motta, C. Murphy, F. Nang, M. Narain, V.S. Narasimham, A. Narayanan, H.A. Neal, J.P. Negret, P. Nemethy, D. Norman, L. Oesch, V. Oguri, N. Oshima, D. Owen, P. Padley, A. Para, N. Parashar, Y.M. Park, R. Partridge, N. Parua, M. Paterno, B. Pawlik, J. Perkins, M. Peters, R. Piegaia, H. Piekarz, Y. Pischalnikov, B.G. Pope, H.B. Prosper, S. Protopopescu, J. Qian, P.Z. Quintas, R. Raja, S. Rajagopalan, O. Ramirez, N.W. Reay, S. Reucroft, M. Rijssenbeek, T. Rockwell, M. Roco, P. Rubinov, R. Ruchti, J. Rutherfoord, A. Sánchez-Hernández, A. Santoro, L. Sawyer, R.D. Schamberger, H. Schellman, J. Sculli, E. Shabalina, C. Shaffer, H.C. Shankar, R.K. Shivpuri, D. Shpakov, M. Shupe, R.A. Sidwell, H. Singh, J.B. Singh, V. Sirotenko, E. Smith, R.P. Smith, R. Snihur, G.R. Snow, J. Snow, S. Snyder, J. Solomon, M. Sosebee, N. Sotnikova, M. Souza, N.R. Stanton, G. Steinbrück, R.W. Stephens, M.L. Stevenson, F. Stichelbaut, D. Stoker, V. Stolin, D.A. Stoyanova, M. Strauss, K. Streets, M. Strovink, A. Sznajder, P. Tamburello, J. Tarazi, M. Tartaglia, T.L.T. Thomas, J. Thompson, D. Toback, T.G. Trippe, P.M. Tuts, V. Vaniev, N. Varelas, E.W. Varnes, A.A. Volkov, A.P. Vorobiev, H.D. Wahl, G. Wang, J. Warchol, G. Watts, M. Wayne, H. Weerts, A. White, J.T. White, J.A. Wightman, S. Willis, S.J. Wimpenny, J.V.D. Wirjawan, J. Womersley, D.R. Wood, R. Yamada, P. Yamin, T. Yasuda, P. Yepes, K. Yip, C. Yoshikawa, S. Youssef, J. Yu, Y. Yu, B. Zhang, Z. Zhou, Z.H. Zhu, M. Zielinski, D. Zieminska, A. Zieminski, V. Zutshi, E.G. Zverev, and A. Zylberstejn

3 We present the rst measurement of the electron angular distribution parameter 2 in W ! ee events produced in proton-antiproton collisions as a function of the W boson transverse momentum. Our analysis is based on data collected using the DD detector during the 1994{1995 Fermilab Tevatron run. We compare our results with next-to-leading order perturbative QCD, which predicts an angular distribution of (1 1 cos + 2 cos 2), where is the polar angle of the electron in the Collins-Soper frame. In the presence of QCD corrections, the parameters 1 and 2 become functions of p W T , the W boson transverse momentum. This measurement provides a test of next-to-leading order QCD corrections which are a non-negligible contribution to the W boson mass measurement.

We examine properties of tt¯ candidate events in lepton + jets final states to establish the helicities of W bosons in t→W+b decays. Our analysis is based on a direct calculation of a probability density for each event to correspond to a tt¯ final state, as a function of the helicity of the W boson. Using the 125 events/pb of data collected by the DØ experiment at the Fermilab Tevatron pp¯ Collider at s=1.8TeV, we obtain a longitudinal helicity fraction F0=0.56±0.31, consistent with the prediction of F0=0.70 from the standard model.

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Using 85.2 +/- 3.6 pb^-1 of p-pbar collisions collected at sqrt(s)=1.8 TeV with the D0 detector at Fermilab's Tevatron Collider, we present the results of a search for direct pair production of scalar top quarks ~t, the supersymmetric partners of the top quark. We examined events containing two or more jets and missing transverse energy, the signature of light scalar top quark decays to charm quarks and neutralinos. After selections, we observe 27 events while expecting 31.1 +/- 6.4 events from known standard model processes. Comparing these results to next-to-leading-order production cross sections, we exclude a significant region of ~t and neutralino phase space. In particular, we exclude the ~t mass m_~t < 122 GeV/c^2 for a neutralino mass of 45 GeV/c^2.

We have searched for the signature of 3- and 4-body decays of pair-produced scalar top quarks (stop) in the inclusive final state containing an electron, a muon, and significant missing transverse energy using a sample of p (p) over bar events corresponding to 108.3 pb(-1) of data collected with the D empty set detector at Fermilab. The search is done in the framework of the minimal supersymmetric standard model assuming that the neutralino (chi(1)(0)) is the lightest supersymmetric particle and is stable. No evidence for a signal is found and we derive cross-section upper limits as a function of stop ((t) over tilde) and neutralino masses in different decay scenarios leading to the blvchi(1)(0) final state. (C) 2004 Published by Elsevier B.V.

We present the results of a search for the production of new particles decaying into two jets in (p) over barp collisions at roots=1.8 TeV, using the DO 1992-1995 data set corresponding to 109 pb(-1). We exclude at the 95% confidence level the production of excited quarks (q*) with masses below 775 GeV/c(2), the most restrictive limit to date. We also exclude standard-model-like W' (Z') bosons with masses between 300 and 800 GeV/c(2) (400 and 640 GeV/c(2)). A W-' boson with mass <786 GeV/c(2) has been excluded by previous measurements, and our lower limit is therefore the most stringent to date.

A search for narrow resonances that decay into tt pairs has been performed using 130 pb(-1) of data in the lepton + jets channel collected by the Dphi detector in pp collisions at square root of (s)=1.8 TeV. There is no significant deviation observed from the standard-model predictions at a top-quark mass of 175 GeV/c2. We therefore present upper limits at the 95% confidence level on the product of the production cross section and branching fraction to tt for narrow resonances as a function of the resonance mass MX. These limits are used to exclude the existence of a leptophobic top-color particle with mass MX<560 GeV/c2, using a theoretical cross section for a width GammaX=0.012MX.