Eur. Phys. J. C 70, 945-963 (2010)
https://doi.org/10.1140/epjc/s10052-010-1498-9

Measurement of high-Q ² charged current deep inelastic scattering cross sections with a longitudinally polarised positron beam at HERA

¹ Argonne National Laboratory, Argonne, IL, 60439-4815, USA
² Andrews University, Berrien Springs, MI, 49104-0380, USA
³ INFN Bologna, Bologna, Italy
⁴ University and INFN Bologna, Bologna, Italy
⁵ Physikalisches Institut der Universität Bonn, Bonn, Germany
⁶ H.H. Wills Physics Laboratory, University of Bristol, Bristol, UK
⁷ Department of Physics, Panjab University, Chandigarh, India
⁸ Physics Department and INFN, Calabria University, Cosenza, Italy
⁹ Institute for Universe and Elementary Particles, Chonnam National University, Kwangju, South Korea
¹⁰ Jabatan Fizik, Universiti Malaya, 50603, Kuala Lumpur, Malaysia
¹¹ Nevis Laboratories, Columbia University, Irvington on Hudson, New York, 10027, USA
¹² The Henryk Niewodniczanski Institute of Nuclear Physics, Polish Academy of Sciences, Cracow, Poland
¹³ Faculty of Physics and Applied Computer Science, AGH-University of Science and Technology, Cracow, Poland
¹⁴ Department of Physics, Jagellonian University, Cracow, Poland
¹⁵ Deutsches Elektronen-Synchrotron DESY, Hamburg, Germany
¹⁶ Deutsches Elektronen-Synchrotron DESY, Zeuthen, Germany
¹⁷ INFN Florence, Florence, Italy
¹⁸ University and INFN Florence, Florence, Italy
¹⁹ Fakultät für Physik der Universität Freiburg i.Br., Freiburg i.Br., Germany
²⁰ School of Physics and Astronomy, University of Glasgow, Glasgow, UK
²¹ Department of Engineering in Management and Finance, University of the Aegean, Chios, Greece
²² Institute of Experimental Physics, Hamburg University, Hamburg, Germany
²³ Imperial College London, High Energy Nuclear Physics Group, London, UK
²⁴ Institute of Particle and Nuclear Studies, KEK, Tsukuba, Japan
²⁵ Institute of Physics and Technology of Ministry of Education and Science of Kazakhstan, Almaty, Kazakhstan
²⁶ Institute for Nuclear Research, National Academy of Sciences, Kiev, Ukraine
²⁷ Kiev National University, Kiev, Ukraine
²⁸ Center for High Energy Physics, Kyungpook National University, Daegu, South Korea
²⁹ Institut de Physique Nucléaire, Université Catholique de Louvain, Louvain-la-Neuve, Belgium
³⁰ Departamento de Física Teórica, Universidad Autónoma de Madrid, Madrid, Spain
³¹ Department of Physics, McGill University, Montréal, Québec, H3A 2T8, Canada
³² Faculty of General Education, Meiji Gakuin University, Yokohama, Japan
³³ Moscow Engineering Physics Institute, Moscow, Russia
³⁴ Institute of Nuclear Physics, Moscow State University, Moscow, Russia
³⁵ Max-Planck-Institut für Physik, München, Germany
³⁶ NIKHEF and University of Amsterdam, Amsterdam, Netherlands
³⁷ Physics Department, Ohio State University, Columbus, OH, 43210, USA
³⁸ Department of Physics, University of Oxford, Oxford, UK
³⁹ INFN Padova, Padova, Italy
⁴⁰ Dipartimento di Fisica dell’ Università and INFN, Padova, Italy
⁴¹ Department of Physics, Pennsylvania State University, University Park, PA, 16802, USA
⁴² Polytechnic University, Sagamihara, Japan
⁴³ Dipartimento di Fisica, Università ‘La Sapienza’ and INFN, Rome, Italy
⁴⁴ Rutherford Appleton Laboratory, Chilton, Didcot, Oxon, UK
⁴⁵ Raymond and Beverly Sackler Faculty of Exact Sciences, School of Physics, Tel Aviv University, Tel Aviv, Israel
⁴⁶ Department of Physics, Tokyo Institute of Technology, Tokyo, Japan
⁴⁷ Department of Physics, University of Tokyo, Tokyo, Japan
⁴⁸ Department of Physics, Tokyo Metropolitan University, Tokyo, Japan
⁴⁹ Università di Torino and INFN, Torino, Italy
⁵⁰ Università del Piemonte Orientale, Novara, Italy
⁵¹ INFN, Torino, Italy
⁵² Department of Physics, University of Toronto, Toronto, ON, M5S 1A7, Canada
⁵³ Physics and Astronomy Department, University College London, London, UK
⁵⁴ Institute of Experimental Physics, Warsaw University, Warsaw, Poland
⁵⁵ Institute for Nuclear Studies, Warsaw, Poland
⁵⁶ Department of Particle Physics, Weizmann Institute, Rehovot, Israel
⁵⁷ Department of Physics, University of Wisconsin, Madison, WI, 53706, USA
⁵⁸ Department of Physics, York University, Ontario, M3J 1P3, Canada

levy@alzt.tau.ac.il

Received: 24 August 2010
Revised: 16 October 2010
Published online: 18 November 2010

Abstract

Measurements of the cross sections for charged current deep inelastic scattering in e ⁺ p collisions with a longitudinally polarised positron beam are presented. The measurements are based on a data sample with an integrated luminosity of 132 pb⁻¹ collected with the ZEUS detector at HERA at a centre-of-mass energy of 318 GeV. The total cross section is presented at positive and negative values of the longitudinal polarisation of the positron beams. The single-differential cross-sections dσ/dQ ², dσ/dx and dσ/dy are presented for Q ²>200 GeV². The reduced cross-section is presented in the kinematic range 200<Q ²<60 000 GeV² and 0.006<x<0.562. The measurements agree well with the predictions of the Standard Model. The results are used to determine a lower limit on the mass of a hypothetical right-handed W boson.