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arXiv · hep-ex/0406017

Initial State Radiation and Inclusive Hadron Production Measurements at BABAR

Abstract

The status of analysis of processes with hard photon emitted from the initial state (ISR) at BABAR is presented. We tag events by the presence of a hard photon in the detector, then reconstruct mu+mu- and several exclusive hadronic final states. The invariant mass of the final state determines an effective collision center of mass energy at which these measurements can be compared with results from direct e+e- annihilation process. The first results on e+e- --> 2h+2h-, where h=pi,K and on e+e- --> J/psi, obtained with a sample of 89.3/fb, are presented. Measurements of inclusive eta, pi+, K+ and p/anti-p production cross sections below the Y(4S) resonance are also presented. These measurements have nearly complete momentum coverage and precision comparable to the best measurements at higher energies. They therefore allow for precise tests of QCD predictions and fragmentation models at 10.54 GeV and of their scaling properties.

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BibTeXRIS

F. Anulli. 2004-06-06. Initial State Radiation and Inclusive Hadron Production Measurements at BABAR. https://arxiv.org/abs/hep-ex/0406017

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