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Search for single top quark production in ep collisions at HERA

Aktas, A ; Andreev, V ; Anthonis, T ; Asmone, A ; Babaev, A ; Backovic, S ; Bahr, J ; Baranov, P ; Barrelet, E and Bartel, W , et al. (2004) In European Physical Journal C. Particles and Fields 33(1). p.9-22
Abstract
A search for single top quark production is performed in e(+/-) pcollisions at HERA. The search exploits data corresponding to an integrated luminosity of 118.3 pb(-1). A model for the anomalous production of top quarks in a flavour changing neutral current process involving a tugamma coupling is investigated. Decays of top quarks into a b quark and a W boson are considered in the leptonic and the hadronic decay channels of the W. Both a cut-based analysis and a multivariate likelihood analysis are performed to discriminate anomalous top quark production from Standard Model background processes. In the leptonic channel, 5 events are found while 1.31 +/- 0.22 events are expected from the Standard Model background. In the hadronic channel,... (More)
A search for single top quark production is performed in e(+/-) pcollisions at HERA. The search exploits data corresponding to an integrated luminosity of 118.3 pb(-1). A model for the anomalous production of top quarks in a flavour changing neutral current process involving a tugamma coupling is investigated. Decays of top quarks into a b quark and a W boson are considered in the leptonic and the hadronic decay channels of the W. Both a cut-based analysis and a multivariate likelihood analysis are performed to discriminate anomalous top quark production from Standard Model background processes. In the leptonic channel, 5 events are found while 1.31 +/- 0.22 events are expected from the Standard Model background. In the hadronic channel, no excess above the expectation for Standard Model processes is found. These observations lead to a cross section (ep --> e t X) = 0.29(-0.14)(+0.15) pb at roots = 319 GeV. Alternatively, assuming that the observed events are due to a statistical fluctuation, upper limits of 0.55 pb on the anomalous top production cross section and of 0.27 on the tugamma coupling k(tugamma) are established at the 95% confidence level. (Less)
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organization
publishing date
type
Contribution to journal
publication status
published
subject
in
European Physical Journal C. Particles and Fields
volume
33
issue
1
pages
9 - 22
publisher
Springer
external identifiers
  • wos:000189173600002
  • scopus:2442504783
ISSN
1434-6044
DOI
10.1140/epjc/s2003-01588-2
language
English
LU publication?
yes
id
18678fae-6853-48f9-bd85-2f1367988fbb (old id 286460)
date added to LUP
2016-04-01 16:38:10
date last changed
2023-01-05 01:05:23
@article{18678fae-6853-48f9-bd85-2f1367988fbb,
  abstract     = {{A search for single top quark production is performed in e(+/-) pcollisions at HERA. The search exploits data corresponding to an integrated luminosity of 118.3 pb(-1). A model for the anomalous production of top quarks in a flavour changing neutral current process involving a tugamma coupling is investigated. Decays of top quarks into a b quark and a W boson are considered in the leptonic and the hadronic decay channels of the W. Both a cut-based analysis and a multivariate likelihood analysis are performed to discriminate anomalous top quark production from Standard Model background processes. In the leptonic channel, 5 events are found while 1.31 +/- 0.22 events are expected from the Standard Model background. In the hadronic channel, no excess above the expectation for Standard Model processes is found. These observations lead to a cross section (ep --> e t X) = 0.29(-0.14)(+0.15) pb at roots = 319 GeV. Alternatively, assuming that the observed events are due to a statistical fluctuation, upper limits of 0.55 pb on the anomalous top production cross section and of 0.27 on the tugamma coupling k(tugamma) are established at the 95% confidence level.}},
  author       = {{Aktas, A and Andreev, V and Anthonis, T and Asmone, A and Babaev, A and Backovic, S and Bahr, J and Baranov, P and Barrelet, E and Bartel, W and Baumgartner, S and Becker, J and Beckingham, M and Behnke, O and Behrendt, O and Belousov, A and Berger, C and Berndt, T and Bizot, JC and Bohme, J and Boenig, MO and Boudry, V and Bracinik, J and Braunschweig, W and Brisson, V and Broker, HB and Brown, DP and Bruncko, D and Busser, FW and Bunyatyan, A and Buschhorn, G and Bystritskaya, L and Campbell, AJ and Caron, S and Cassol-Brunner, F and Chekelian, V and Clarke, D and Collard, C and Contreras, JG and Coppens, YR and Coughlan, JA and Cousinou, MC and Cox, BE and Cozzika, G and Cvach, J and Dainton, JB and Dau, WD and Daum, K and Delcourt, B and Delerue, N and Demirchyan, R and De Roeck, A and De Wolf, EA and Diaconu, C and Dingfelder, J and Dodonov, V and Dowell, JD and Dubak, A and Duprel, C and Eckerlin, G and Efremenko, V and Egli, S and Eichler, R and Eisele, F and Ellerbrock, M and Elsen, E and Erdmann, M and Erdmann, W and Faulkner, PJW and Favart, L and Fedotov, A and Felst, R and Ferencei, J and Fleischer, M and Fleischmann, P and Fleming, YH and Flucke, G and Flugge, G and Fomenko, A and Foresti, I and Formanek, J and Franke, G and Frising, G and Gabathuler, E and Gabathuler, K and Garvey, J and Gassner, J and Gayler, J and Gerhards, R and Gerlich, C and Ghazaryan, S and Goerlich, L and Gogitidze, N and Gorbounov, S and Grab, C and Grabski, V and Grassler, H and Greenshaw, T and Gregori, M and Grindhammer, G and Haidt, D and Hajduk, L and Haller, J and Heinzelmann, G and Henderson, RCW and Henschel, H and Henshaw, O and Heremans, R and Herrera, G and Herynek, I and Hildebrandt, M and Hiller, KH and Hladky, J and Hoting, P and Hoffmann, D and Horisberger, R and Hovhannisyan, A and Ibbotson, M and Jacquet, M and Janauschek, L and Janssen, X and Jemanov, V and Jönsson, Leif and Johnson, C and Johnson, DP and Jung, Hannes and Kant, D and Kapichine, M and Karlsson, Martin and Katzy, J and Keil, F and Keller, N and Kennedy, J and Kenyon, IR and Kiesling, C and Klein, M and Kleinwort, C and Kluge, T and Knies, G and Koblitz, B and Kolya, SD and Korbel, V and Kostka, P and Koutouev, R and Kropivnitskaya, A and Kroseberg, J and Kueckens, J and Kuhr, T and Landon, MPJ and Lange, W and Lastovicka, T and Laycock, P and Lebedev, A and Leissner, B and Lemrani, R and Lendermann, V and Levonian, S and List, B and Lobodzinska, E and Loktionova, N and Lopez-Fernandez, R and Lubimov, V and Lueders, H and Luders, S and Luke, D and Lytkin, L and Makankine, A and Malden, N and Malinovski, E and Mangano, S and Marage, P and Marks, J and Marshall, R and Martyn, HU and Martyniak, J and Maxfield, SJ and Meer, D and Mehta, A and Meier, K and Meyer, AB and Meyer, H and Meyer, J and Michine, S and Mikocki, S and Milstead, D and Moreau, F and Morozov, A and Morris, JV and Muller, K and Murin, P and Nagovizin, V and Naroska, B and Naumann, J and Naumann, T and Newman, PR and Niebergall, F and Niebuhr, C and Nikitin, D and Nowak, G and Nozicka, M and Olivier, B and Olsson, JE and Ozerov, D and Pascaud, C and Patel, GD and Peez, M and Perez, E and Petrukhin, A and Pitzl, D and Poschl, R and Povh, B and Raicevic, N and Rauschenberger, J and Reimer, P and Reisert, B and Risler, C and Rizvi, E and Robmann, P and Roosen, R and Rostovtsev, A and Rusakov, S and Rybicki, K and Sankey, DPC and Sauvan, E and Schatzel, S and Scheins, J and Schilling, FP and Schleper, P and Schmidt, D and Schmidt, S and Schmitt, S and Schneider, M and Schoeffel, L and Schoning, A and Schroder, V and Schultz-Coulon, HC and Schwanenberger, C and Sedlak, K and Sefkow, F and Sheviakov, I and Shtarkov, LN and Sirois, Y and Sloan, T and Smirnov, P and Soloviev, Y and South, D and Spaskov, V and Specka, A and Spitzer, H and Stamen, R and Stella, B and Stiewe, J and Strauch, I and Straumann, U and Thompson, G and Thompson, PD and Tomasz, F and Traynor, D and Truol, P and Tsipolitis, G and Tsurin, I and Turnau, J and Turney, JE and Tzamariudaki, E and Uraev, A and Urban, M and Usik, A and Valkar, S and Valkarova, A and Vallee, C and Van Mechelen, P and Trevino, AV and Vassiliev, S and Vazdik, Y and Veelken, C and Vest, A and Vichnevski, A and Volchinski, V and Wacker, K and Wagner, J and Waugh, B and Weber, G and Weber, R and Wegener, D and Werner, C and Werner, N and Wessels, M and Wessling, B and Winde, M and Winter, GG and Wissing, C and Woehrling, EE and Wunsch, E and Zacek, J and Zalesak, J and Zhang, Z and Zhokin, A and Zomer, F and zur Nedden, M}},
  issn         = {{1434-6044}},
  language     = {{eng}},
  number       = {{1}},
  pages        = {{9--22}},
  publisher    = {{Springer}},
  series       = {{European Physical Journal C. Particles and Fields}},
  title        = {{Search for single top quark production in ep collisions at HERA}},
  url          = {{http://dx.doi.org/10.1140/epjc/s2003-01588-2}},
  doi          = {{10.1140/epjc/s2003-01588-2}},
  volume       = {{33}},
  year         = {{2004}},
}