https://doi.org/10.1140/epjc/s10052-012-1935-z
Regular Article - Theoretical Physics
Bound–free pair production in ultra–relativistic ion collisions at the LHC collider: analytic approach to the total and differential cross sections
1
Physikalisches Institut der Universität Heidelberg, Philosophenweg 12, 69120, Heidelberg, Germany
2
GSI Helmholtzzentrum für Schwerionenforschung GmbH, Planckstraße 1, 64291, Darmstadt, Germany
3
Department of Physics, Missouri University of Science and Technology, Rolla, MO, 65409-0640, USA
4
Sobolev Institute of Mathematics, Koptyug avenue 4, 630090, Novosibirsk, Russia
5
Novosibirsk State University, Pirogova Street 2, 630090, Novosibirsk, Russia
* e-mail: surz@physi.uni-heidelberg.de
Received:
16
January
2012
Published online:
27
March
2012
A theoretical investigation of the bound–free electron–positron pair production in relativistic heavy ion collisions is presented. Special attention is paid to the positrons emitted under large angles with respect to the beam direction. The measurement of these positrons in coincidence with the down–charged ions is in principle feasible by LHC experiments. In order to provide reliable estimates for such measurements, we employ the equivalent photon approximation together with the Sauter approach and derive simple analytic expressions for the differential pair-production cross section, which compare favorably to the results of available numerical calculations. Based on the analytic expressions, detailed calculations are performed for collisions of bare Pb82+ ions, taking typical experimental conditions of the LHC experiments into account. We find that the expected count rate strongly depends on the experimental parameters and may be significantly enhanced by increasing the positron-detector acceptance cone.
© Springer-Verlag / Società Italiana di Fisica, 2012