Search for squarks in R-parity violating supersymmetry in ep collisions at HERA

F.D. Aaron; C. Alexa; V. Andreev; S. Backovic; A. Baghdasaryan; S. Baghdasaryan; E. Barrelet; W. Bartel; K. Begzsuren; A. Belousov; J.C. Bizot; V. Boudry; I. Bozovic-Jelisavcic; J. Bracinik; G. Brandt; M. Brinkmann; V. Brisson; D. Britzger; D. Bruncko; A. Bunyatyan; G. Buschhorn; L. Bystritskaya; A.J. Campbell; K.B. Cantun Avila; F. Ceccopieri; K. Cerny; V. Cerny; V. Chekelian; A. Cholewa; J.G. Contreras; J.A. Coughlan; J. Cvach; J.B. Dainton; K. Daum; B. Delcourt; J. Delvax; E.A. Wolf; C. Diaconu; M. Dobre; V. Dodonov; A. Dossanov; A. Dubak; G. Eckerlin; S. Egli; A. Eliseev; E. Elsen; L. Favart; A. Fedotov; R. Felst; J. Feltesse; J. Ferencei; D.-J. Fischer; M. Fleischer; A. Fomenko; E. Gabathuler; J. Gayler; S. Ghazaryan; A. Glazov; L. Goerlich; N. Gogitidze; M. Gouzevitch; C. Grab; A. Grebenyuk; T. Greenshaw; B.R. Grell; G. Grindhammer; S. Habib; D. Haidt; C. Helebrant; R.C.W. Henderson; E. Hennekemper; H. Henschel; M. Herbst; G. Herrera; M. Hildebrandt; K.H. Hiller; D. Hoffmann; R. Horisberger; T. Hreus; F. Huber; M. Jacquet; X. Janssen; L. Jönsson; A.W. Jung; H. Jung; M. Kapichine; J. Katzy; I.R. Kenyon; C. Kiesling; M. Klein; C. Kleinwort; T. Kluge; A. Knutsson; R. Kogler; P. Kostka; M. Kraemer; J. Kretzschmar; K. Krüger; K. Kutak; M.P.J. Landon; W. Lange; G. Laštovička-Medin; P. Laycock; A. Lebedev; V. Lendermann; S. Levonian; K. Lipka; B. List; J. List; N. Loktionova; R. Lopez-Fernandez; V. Lubimov; A. Makankine; E. Malinovski; P. Marage; H.-U. Martyn; S.J. Maxfield; A. Mehta; A.B. Meyer; H. Meyer; J. Meyer; S. Mikocki; I. Milcewicz-Mika; F. Moreau; A. Morozov; J.V. Morris; M.U. Mozer; M. Mudrinic; K. Müller; Th. Naumann; P.R. Newman; C. Niebuhr; D. Nikitin; G. Nowak; K. Nowak; J.E. Olsson; S. Osman; D. Ozerov; P. Pahl; V. Palichik; I. Panagoulias; M. Pandurovic; Th. Papadopoulou; C. Pascaud; G.D. Patel; E. Perez; A. Petrukhin; I. Picuric; S. Piec; H. Pirumov; D. Pitzl; R. Plačakytė; B. Pokorny; R. Polifka; B. Povh; V. Radescu; N. Raicevic; T. Ravdandorj; P. Reimer; E. Rizvi; P. Robmann; R. Roosen; A. Rostovtsev; M. Rotaru; J.E. Ruiz Tabasco; S. Rusakov; D. Šálek; D.P.C. Sankey; M. Sauter; E. Sauvan; S. Schmitt; L. Schoeffel; A. Schöning; H.-C. Schultz-Coulon; F. Sefkow; L.N. Shtarkov; S. Shushkevich; T. Sloan; I. Smiljanic; Y. Soloviev; P. Sopicki; D. South; V. Spaskov; A. Specka; Z. Staykova; M. Steder; B. Stella; G. Stoicea; U. Straumann; D. Sunar; T. Sykora; G. Thompson; P.D. Thompson; T. Toll; T.H. Tran; D. Traynor; P. Truöl; I. Tsakov; B. Tseepeldorj; J. Turnau; K. Urban; A. Valkárová; C. Vallée; P. Mechelen; Y. Vazdik; M. Driesch; D. Wegener; E. Wünsch; J. Žáček; J. Zálešák; Z. Zhang; A. Zhokin; H. Zohrabyan; F. Zomer

doi:10.1140/epjc/s10052-011-1572-y

2022 Impact factor 4.4

Particles and Fields

Open Access

Eur. Phys. J. C (2011) 71: 1572
https://doi.org/10.1140/epjc/s10052-011-1572-y

Regular Article - Experimental Physics

Search for squarks in R-parity violating supersymmetry in ep collisions at HERA

The H1 Collaboration
F.D. Aaron⁵, C. Alexa⁵, V. Andreev²⁵, S. Backovic³⁰, A. Baghdasaryan³⁸, S. Baghdasaryan³⁸, E. Barrelet²⁹, W. Bartel¹¹, K. Begzsuren³⁵, A. Belousov²⁵, J.C. Bizot²⁷, V. Boudry²⁸, I. Bozovic-Jelisavcic², J. Bracinik³, G. Brandt¹¹, M. Brinkmann¹¹, V. Brisson²⁷, D. Britzger¹¹, D. Bruncko¹⁶, A. Bunyatyan¹³^,38, G. Buschhorn²⁶, L. Bystritskaya²⁴, A.J. Campbell¹¹, K.B. Cantun Avila²², F. Ceccopieri⁴, K. Cerny³², V. Cerny¹⁶, V. Chekelian²⁶, A. Cholewa¹¹, J.G. Contreras²², J.A. Coughlan⁶, J. Cvach³¹, J.B. Dainton¹⁸, K. Daum³⁷, B. Delcourt²⁷, J. Delvax⁴, E.A. Wolf⁴, C. Diaconu²¹, M. Dobre¹², V. Dodonov¹³, A. Dossanov²⁶, A. Dubak³⁰, G. Eckerlin¹¹, S. Egli³⁶, A. Eliseev²⁵, E. Elsen¹¹, L. Favart⁴, A. Fedotov²⁴, R. Felst¹¹, J. Feltesse¹⁰, J. Ferencei¹⁶, D.-J. Fischer¹¹, M. Fleischer¹¹, A. Fomenko²⁵, E. Gabathuler¹⁸, J. Gayler¹¹, S. Ghazaryan¹¹, A. Glazov¹¹, L. Goerlich⁷, N. Gogitidze²⁵, M. Gouzevitch¹¹, C. Grab⁴⁰, A. Grebenyuk¹¹, T. Greenshaw¹⁸, B.R. Grell¹¹, G. Grindhammer²⁶, S. Habib¹¹, D. Haidt¹¹, C. Helebrant¹¹, R.C.W. Henderson¹⁷, E. Hennekemper¹⁵, H. Henschel³⁹, M. Herbst¹⁵, G. Herrera²³, M. Hildebrandt³⁶, K.H. Hiller³⁹, D. Hoffmann²¹, R. Horisberger³⁶, T. Hreus⁴, F. Huber¹⁴, M. Jacquet²⁷, X. Janssen⁴, L. Jönsson²⁰, A.W. Jung¹⁵, H. Jung¹¹^,4, M. Kapichine⁹, J. Katzy¹¹, I.R. Kenyon³, C. Kiesling²⁶, M. Klein¹⁸, C. Kleinwort¹¹, T. Kluge¹⁸, A. Knutsson¹¹, R. Kogler²⁶, P. Kostka³⁹, M. Kraemer¹¹, J. Kretzschmar¹⁸, K. Krüger¹⁵^*, K. Kutak¹¹, M.P.J. Landon¹⁹, W. Lange³⁹, G. Laštovička-Medin³⁰, P. Laycock¹⁸, A. Lebedev²⁵, V. Lendermann¹⁵, S. Levonian¹¹, K. Lipka¹¹, B. List¹², J. List¹¹, N. Loktionova²⁵, R. Lopez-Fernandez²³, V. Lubimov²⁴, A. Makankine⁹, E. Malinovski²⁵, P. Marage⁴, H.-U. Martyn¹, S.J. Maxfield¹⁸, A. Mehta¹⁸, A.B. Meyer¹¹, H. Meyer³⁷, J. Meyer¹¹, S. Mikocki⁷, I. Milcewicz-Mika⁷, F. Moreau²⁸, A. Morozov⁹, J.V. Morris⁶, M.U. Mozer⁴, M. Mudrinic², K. Müller⁴¹, Th. Naumann³⁹, P.R. Newman³, C. Niebuhr¹¹, D. Nikitin⁹, G. Nowak⁷, K. Nowak¹¹, J.E. Olsson¹¹, S. Osman²⁰, D. Ozerov²⁴, P. Pahl¹¹, V. Palichik⁹, I. Panagoulias¹¹, M. Pandurovic², Th. Papadopoulou¹¹, C. Pascaud²⁷, G.D. Patel¹⁸, E. Perez¹⁰, A. Petrukhin¹¹, I. Picuric³⁰, S. Piec¹¹, H. Pirumov¹⁴, D. Pitzl¹¹, R. Plačakytė¹², B. Pokorny³², R. Polifka³², B. Povh¹³, V. Radescu¹⁴, N. Raicevic³⁰, T. Ravdandorj³⁵, P. Reimer³¹, E. Rizvi¹⁹, P. Robmann⁴¹, R. Roosen⁴, A. Rostovtsev²⁴, M. Rotaru⁵, J.E. Ruiz Tabasco²², S. Rusakov²⁵, D. Šálek³², D.P.C. Sankey⁶, M. Sauter¹⁴, E. Sauvan²¹, S. Schmitt¹¹, L. Schoeffel¹⁰, A. Schöning¹⁴, H.-C. Schultz-Coulon¹⁵, F. Sefkow¹¹, L.N. Shtarkov²⁵, S. Shushkevich²⁶, T. Sloan¹⁷, I. Smiljanic², Y. Soloviev²⁵, P. Sopicki⁷, D. South¹¹, V. Spaskov⁹, A. Specka²⁸, Z. Staykova¹¹, M. Steder¹¹, B. Stella³³, G. Stoicea⁵, U. Straumann⁴¹, D. Sunar⁴, T. Sykora³²^,4, G. Thompson¹⁹, P.D. Thompson³, T. Toll¹¹, T.H. Tran²⁷, D. Traynor¹⁹, P. Truöl⁴¹, I. Tsakov³⁴, B. Tseepeldorj³⁵, J. Turnau⁷, K. Urban¹⁵, A. Valkárová³², C. Vallée²¹, P. Mechelen⁴, Y. Vazdik²⁵, M. Driesch¹¹, D. Wegener⁸, E. Wünsch¹¹, J. Žáček³², J. Zálešák³¹, Z. Zhang²⁷, A. Zhokin²⁴, H. Zohrabyan³⁸ and F. Zomer²⁷

¹ I. Physikalisches Institut der RWTH, Aachen, Germany
² Vinca Institute of Nuclear Sciences, University of Belgrade, 1100, Belgrade, Serbia
³ School of Physics and Astronomy, University of Birmingham, Birmingham, UK
⁴ Inter-University Institute for High Energies ULB-VUB, Brussels and Universiteit Antwerpen, Antwerpen, Belgium
⁵ National Institute for Physics and Nuclear Engineering (NIPNE), Bucharest, Romania
⁶ Rutherford Appleton Laboratory, Chilton, Didcot, UK
⁷ Institute for Nuclear Physics, Cracow, Poland
⁸ Institut für Physik, TU Dortmund, Dortmund, Germany
⁹ Joint Institute for Nuclear Research, Dubna, Russia
¹⁰ CEA, DSM/Irfu, CE-Saclay, Gif-sur-Yvette, France
¹¹ DESY, Hamburg, Germany
¹² Institut für Experimentalphysik, Universität Hamburg, Hamburg, Germany
¹³ Max-Planck-Institut für Kernphysik, Heidelberg, Germany
¹⁴ Physikalisches Institut, Universität Heidelberg, Heidelberg, Germany
¹⁵ Kirchhoff-Institut für Physik, Universität Heidelberg, Heidelberg, Germany
¹⁶ Institute of Experimental Physics, Slovak Academy of Sciences, Košice, Slovak Republic
¹⁷ Department of Physics, University of Lancaster, Lancaster, UK
¹⁸ Department of Physics, University of Liverpool, Liverpool, UK
¹⁹ Queen Mary and Westfield College, London, UK
²⁰ Physics Department, University of Lund, Lund, Sweden
²¹ CPPM, Aix-Marseille Université, CNRS/IN2P3, Marseille, France
²² Departamento de Fisica Aplicada, CINVESTAV, Mérida, Yucatán, Mexico
²³ Departamento de Fisica, CINVESTAV IPN, México City, Mexico
²⁴ Institute for Theoretical and Experimental Physics, Moscow, Russia
²⁵ Lebedev Physical Institute, Moscow, Russia
²⁶ Max-Planck-Institut für Physik, München, Germany
²⁷ LAL, Université Paris-Sud, CNRS/IN2P3, Orsay, France
²⁸ LLR, Ecole Polytechnique, CNRS/IN2P3, Palaiseau, France
²⁹ LPNHE, Université Pierre et Marie Curie Paris 6, Université Denis Diderot Paris 7, CNRS/IN2P3, Paris, France
³⁰ Faculty of Science, University of Montenegro, Podgorica, Montenegro
³¹ Institute of Physics, Academy of Sciences of the Czech Republic, Praha, Czech Republic
³² Faculty of Mathematics and Physics, Charles University, Praha, Czech Republic
³³ Dipartimento di Fisica, Università di Roma Tre and INFN Roma 3, Rome, Italy
³⁴ Institute for Nuclear Research and Nuclear Energy, Sofia, Bulgaria
³⁵ Institute of Physics and Technology of the Mongolian Academy of Sciences, Ulaanbaatar, Mongolia
³⁶ Paul Scherrer Institut, Villigen, Switzerland
³⁷ Fachbereich C, Universität Wuppertal, Wuppertal, Germany
³⁸ Yerevan Physics Institute, Yerevan, Armenia
³⁹ DESY, Zeuthen, Germany
⁴⁰ Institut für Teilchenphysik, ETH, Zürich, Switzerland
⁴¹ Physik-Institut der Universität Zürich, Zürich, Switzerland

^* e-mail: kruegerk@mail.desy.de

Received: 30 November 2010
Revised: 24 January 2011
Published online: 1 March 2011

Abstract

A search for squarks in R-parity violating supersymmetry is performed in e ^± p collisions at HERA using the H1 detector. The full data sample taken at a centre-of-mass energy GeV is used for the analysis, corresponding to an integrated luminosity of 255 pb⁻¹ of e ⁺ p and 183 pb⁻¹ of e ⁻ p collision data. The resonant production of squarks via a Yukawa coupling λ′ is considered, taking into account direct and indirect R-parity violating decay modes. Final states with jets and leptons are investigated. No evidence for squark production is found and mass dependent limits on λ′ are obtained in the framework of the Minimal Supersymmetric Standard Model and in the Minimal Supergravity Model. In the considered part of the parameter space, for a Yukawa coupling of electromagnetic strength λ′=0.3, squarks of all flavours are excluded up to masses of 275 GeV at 95% confidence level, with down-type squarks further excluded up to masses of 290 GeV.