Nucleon form factors, <Emphasis Type="Bold">B</Emphasis>-meson factories and the radiative return

The feasibility of a measurement of the electric and magnetic nucleon form factors at B-meson factories through the radiative return is studied. Angular distributions allow for a separation of the contributions from the two form factors. The distributions are presented for the laboratory and the hadronic rest frame, and the advantages of different coordinate systems are investigated. It is demonstrated that Q ² values up to 8 or even 9 GeV² are within reach. The Monte Carlo event generator PHOKHARA is extended to nucleon final states, and results are presented which include next-to-leading order radiative corrections from initial-state radiation. The impact of angular cuts on rates and distributions is investigated and the relative importance of radiative corrections is analyzed.Received: 8 March 2004, Revised: 12 April 2004, Published online: 9 June 2004Work supported in part by BMBF under grant number 05HT9VKB0, EC 5th Framework Programme under contract HPRN-CT-2002-00311 (EURIDICE network), Polish State Committee for Scientific Research (KBN) under contract 2 P03B 017 24, BFM2002-00568, Generalitat Valenciana under grant GRUPOS03/013, and MCyT under grant FPA-2001-3031.