Bonn 2010 – wissenschaftliches Programm
HK 4.7: Vortrag
Montag, 15. März 2010, 18:45–19:00, HG III
Investigation of the η-Dalitz decay and measurement of the electromagnetic form factor. — •Henning Berghaeuser — for the A2-Collaboration, II. Physikalisches Institut, Gießen, Deutschland, supported by European Graduate School, Giessen-Copenhagen
The main experimental problem in measuring Dalitz decays of neutral mesons is a clean e−/+ / π−/+ discrimination. It is shown that these decays can be measured with the Crystal Ball and TAPS detector setup at MAMI-C in Mainz despite of the fact, that these detectors are pure calorimeter systems. The η-Dalitz decay (η → e+e−γ) was measured exclusively, thus all particles in the final state were detected. This allowed to exploit the full kinematic information (such as momentum conservation) to reconstruct the Dalitz events with satisfactory statistics. The electromagnetic formfactor of the η meson has been extracted. These results will be presented. An extension of these studies to the ω meson is discussed.