Muon pair production in electron-proton collisions

Cross sections for the production of two isolated muons up to high di-muon masses are measured in ep collisions at HERA with the H1 detector in a data sample corresponding to an integrated luminosity of 71 pb−1 at a centre of mass energy of √ s = 319 GeV. The results are in good agreement with Standard Model predictions, the dominant process being photon-photon interactions. Additional muons or electrons are searched for in events with two high transverse momentum muons using the full data sample corresponding to 114 pb−1, where data at √ s = 301 GeV and √ s = 319 GeV are combined. Both the di-lepton sample and the tri-lepton sample agree well with the predictions. To be submitted to Phys. Lett. B A. Aktas, V. Andreev, T. Anthonis, A. Asmone, A. Babaev, S. Backovic, J. Bahr, P. Baranov, E. Barrelet, W. Bartel, S. Baumgartner, J. Becker, M. Beckingham, O. Behnke, O. Behrendt, A. Belousov, Ch. Berger, N. Berger, T. Berndt, J.C. Bizot, J. Bohme, M. -O. Boenig, V. Boudry, J. Bracinik, W. Braunschweig, V. Brisson, H. -B. Broker, D.P. Brown, D. Bruncko, F.W. Busser, A. Bunyatyan, G. Buschhorn, L. Bystritskaya, A.J. Campbell, S. Caron, F. Cassol-Brunner, K. Cerny, V. Chekelian, C. Collard, J.G. Contreras, Y.R. Coppens, J.A. Coughlan, M. -C. Cousinou, B.E. Cox, G. Cozzika, J. Cvach, J.B. Dainton, W.D. Dau, K. Daum, B. Delcourt, N. Delerue, R. Demirchyan, A. De Roeck, K. Desch, E.A. De Wolf, C. Diaconu, J. Dingfelder, V. Dodonov, J.D. Dowell, A. Dubak, C. Duprel, G. Eckerlin, V. Efremenko, S. Egli, R. Eichler, F. Eisele, M. Ellerbrock, E. Elsen, M. Erdmann, W. Erdmann, P.J.W. Faulkner, L. Favart, A. Fedotov, R. Felst, J. Ferencei, M. Fleischer, P. Fleischmann, Y.H. Fleming, G. Flucke, G. Flugge, A. Fomenko, I. Foresti, J. Formanek, G. Franke, G. Frising, E. Gabathuler, K. Gabathuler, J. Garvey, J. Gassner, J. Gayler, R. Gerhards, C. Gerlich, S. Ghazaryan, L. Goerlich, N. Gogitidze, S. Gorbounov, C. Grab, V. Grabski, H. Grassler, T. Greenshaw, M. Gregori, G. Grindhammer, D. Haidt, L. Hajduk, J. Haller, G. Heinzelmann, R.C. W. Henderson, H. Henschel, O. Henshaw, R. Heremans, G. Herrera, I. Herynek, R. -D. Heuer, M. Hildebrandt, K.H. Hiller, J. Hladký, P. Hoting, D. Hoffmann, R. Horisberger, A. Hovhannisyan, M. Ibbotson, M. Ismail, M. Jacquet, L. Janauschek, X. Janssen, V. Jemanov, L. Jonsson, C. Johnson, D.P. Johnson, H. Jung, D. Kant, M. Kapichine, M. Karlsson, J. Katzy, N. Keller, J. Kennedy, I.R. Kenyon, C. Kiesling, M. Klein, C. Kleinwort, T. Kluge, G. Knies, A. Knutsson, B. Koblitz, S.D. Kolya, V. Korbel, P. Kostka, R. Koutouev, A. Kropivnitskaya, J. Kroseberg, J. Kuckens, T. Kuhr, M.P.J. Landon, W. Lange, T. Lastovicka, P. Laycock, A. Lebedev, B. Leisner, R. Lemrani, V. Lendermann, S. Levonian, B. List, E. Lobodzinska, N. Loktionova, R. Lopez-Fernandez, V. Lubimov, H. Lueders, S. Luders, D. Luke, T. Lux, L. Lytkin, A. Makankine, N. Malden, E. Malinovski, S. Mangano, P. Marage, J. Marks, R. Marshall, M. Martisikova, H. -U. Martyn, J. Martyniak, S.J. Maxfield, D. Meer, A. Mehta, K. Meier, A.B. Meyer, H. Meyer, J. Meyer, S. Michine, S. Mikocki, I. Milcewicz, D. Milstead, F. Moreau, A. Morozov, I. Morozov, J.V. Morris, M. Mozer, K. Muller, P. Murin, V. Nagovizin, B. Naroska, J. Naumann, Th. Naumann, P.R. Newman, C. Niebuhr, D. Nikitin, G. Nowak, M. Nozicka, B. Olivier, J.E. Olsson, G.Ossoskov, D. Ozerov, C. Pascaud, G.D. Patel, M. Peez, E. Perez, A. Perieanu, A. Petrukhin, D. Pitzl, R. Poschl, B. Portheault, B. Povh, N. Raicevic, J. Rauschenberger, P. Reimer, B. Reisert, C. Risler, E. Rizvi, P. Robmann, R. Roosen, A. Rostovtsev, Z. Rurikova, S. Rusakov, K. Rybicki6,†, D.P.C. Sankey, E. Sauvan, S. Schatzel, J. Scheins, F. -P. Schilling, P. Schleper, S. Schmidt, S. Schmitt, M. Schneider, L. Schoeffel, A. Schoning, V. Schroder, H. -C. Schultz-Coulon, C. Schwanenberger, K. Sedlak, F. Sefkow, I. Sheviakov, L.N. Shtarkov, Y. Sirois, T. Sloan, P. Smirnov, Y. Soloviev, D. South, V. Spaskov, A. Specka, H. Spitzer, R. Stamen, B. Stella, J. Stiewe, I. Strauch, U. Straumann, G. Thompson, P.D. Thompson, F. Tomasz, D. Traynor, P. Truol, G. Tsipolitis, I. Tsurin, J. Turnau, E. Tzamariudaki, A. Uraev, M. Urban, A. Usik, S. Valkar, A. Valkarova, C. Vallee,