Bereiche | Tage | Auswahl | Suche | Downloads | Hilfe
HK: Physik der Hadronen und Kerne
HK 3: Elektromagnetische und hadronische Proben I
HK 3.6: Vortrag
Montag, 17. März 2003, 17:30–17:45, B
Theoretical investigation of the proton polarisation: A possible candidate for future PHELIX-GSI experiments? — •Marco Tomaselli1, Lon-chang Liu2, Daniel Ursescu1, and Thomas Kühl1 — 1Gesellschaft für Schwerionenforschung, D64291 Darmstadt, Germany — 2T-Division, Los Alamos National Laboratory, Los Alamos, NM 87545, USA
Polarisation experiments are important for the investigation of the microscopic structure of the protons. Experiments were done at MAMI [1] tagged photon facility in Mainz in order to determine the electric and magnetic polarizabilities of the protons; they obtained alpha=11.9 e−4 fm3 with 15 % total error and beta=1.2 e−4 fm3 with more than 100 % error. Advance in the field of the new bright sources as PHELIX from GSI coupled with GSI Future Project can offer new possibilities towards better measurements of these parameters [2]. We started ab-initio calculations to study the three quark systems in the search of the radial distribution using the Dynamic Correlation Model (DCM) [3]. In this model the three quark systems via ⟨ qq⟩ [4] ⟨ qq ⟩ [5] excitations modify the structure of the vacuum. The ⟨ qq ⟩ excitation simulates additionally relativistic effects in this dynamic model. According to [6] the harmonic-oscillator states are assumed to represent a convenient set of base states for the calculation. [1] V. Olmos de Leon et al., Eur. Phys. J. A10, 207 (2001). [2] D. Ursescu et al., 2002 in preparation. [3] M. Tomaselli, L.C. Liu et al., Wigner Centennial Conference, 2002; Pècs, Hungary. [4,5] M. Tomaselli, Annals Phys. (N.Y.) 205, 362 (1991); Phys. Rev. C48, 2290 (1993). [6] N. Isgur and G. Karl, Phys. Rev. D19, 2653 (1979).