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arXiv · hep-ex/9809008

The Estimation of the Effective Centre of Mass Energy in q-qbar-gamma Events from DELPHI

P. Abreu·A. De Angelis·G. Della Ricca·D. Fassouliotis·A. Grefrath·N. Kjaer·R. Henriques·M. Mulders·M. Pimenta·L. Vitale
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Abstract

The photon radiation in the initial state lowers the energy available for the e$^+$e$^-$ collisions; this effect is particularly important at LEP2 energies (above the mass of the Z boson). Being aligned to the beam direction, such initial state radiation is mostly undetected. This article describes the procedure used by the DELPHI experiment at LEP to estimate the effective centre-of-mass energy in hadronic events collected at energies above the Z peak. Typical resolutions ranging from 2 to 3 GeV on the effective center-of-mass energy are achieved, depending on the event topology.

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P. Abreu, A. De Angelis, G. Della Ricca, D. Fassouliotis, A. Grefrath, N. Kjaer, R. Henriques, M. Mulders, M. Pimenta, L. Vitale. 1998-09-11. The Estimation of the Effective Centre of Mass Energy in q-qbar-gamma Events from DELPHI. https://doi.org/10.1016/s0168-9002(98)01394-1

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