Eur. Phys. J. C (2011) 71: 1573
https://doi.org/10.1140/epjc/s10052-011-1573-x

Regular Article - Experimental Physics

Measurement of beauty production in deep inelastic scattering at HERA using decays into electrons

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, NY, 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, Univ. of the Aegean, Chios, Greece
²² Institute of Experimental Physics, Hamburg University, Hamburg, Germany
²³ High Energy Nuclear Physics Group, Imperial College London, London, UK
²⁴ KEK, Institute of Particle and Nuclear Studies, 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, Kyiv, Ukraine
²⁷ Department of Nuclear Physics, National Taras Shevchenko University of Kyiv, Kyiv, 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, The 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, and INFN, Torino, Italy
⁵¹ Department of Physics, University of Toronto, Toronto, Ontario, M5S 1A7, Canada
⁵² Physics and Astronomy Department, University College London, London, UK
⁵³ Faculty of Physics, University of Warsaw, Warsaw, Poland
⁵⁴ Institute for Nuclear Studies, Warsaw, Poland
⁵⁵ Department of Particle Physics and Astrophysics, Weizmann Institute, Rehovot, Israel
⁵⁶ Department of Physics, University of Wisconsin, Madison, WI, 53706, USA
⁵⁷ Department of Physics, York University, Toronto, Ontario, M3J 1P3, Canada

^* e-mail: levy@alzt.tau.ac.il

Received: 25 January 2011
Published online: 22 February 2011

Abstract

The production of beauty quarks in ep interactions has been studied with the ZEUS detector at HERA for exchanged four-momentum squared Q ²>10 GeV², using an integrated luminosity of 363 pb⁻¹. The beauty events were identified using electrons from semileptonic b decays with a transverse momentum  GeV and pseudorapidity |η ^e |<1.5. Cross sections for beauty production were measured and compared with next-to-leading-order QCD calculations. The beauty contribution to the proton structure function F ₂ was extracted from the double-differential cross section as a function of Bjorken-x and Q ².