München 2006 – wissenschaftliches Programm
Bereiche | Tage | Auswahl | Suche | Downloads | Hilfe
HK: Physik der Hadronen und Kerne
HK 56: Elektromagnetische und Hadronische Sonden
HK 56.3: Vortrag
Freitag, 24. März 2006, 14:45–15:00, F
4He photodisintegration with realistic nuclear forces — •Sonia Bacca1, Doron Gazit2, Nir Barnea2, Winfried Leidemann3, and Giuseppina Orlandini3 — 1GSI, Plankstr. 1, 64291, Darmstadt, Germany — 2The Racah Institute of Physics, The Hebrew University, 91904, Jerusalem, Israel — 3Dipartimento di Fisica, Universita’ di Trento, I-38050 Povo, Italy and INFN, Gruppo Collegato di Trento
We present the first calculation of the total photodisintegration cross section of 4He with realistic two- and three-body nuclear forces.
We make use of the of the Lorentz Integral Transform (LIT) method to reduce the continuum problem to a bound-state-like equation [1]. We solve it by performing expansions in terms of hyperspherical harmonics (HH). Convergence is accelerated treating the nucleon-nucleon Argonne V18 potential with the powerful approach of effective interaction in the HH (EIHH) [2]. The three-body force Urbana IX is also included, though as bare interaction. The main effect of meson exchange currents is taken into account via the Siegert theorem, in the unretarded dipole approximation.
The cross section exhibits a pronounced giant dipole peak. Good agreement with experimental data ((γ,n) form TUNL and (γ,p) from LLL) is found close to threshold, but at higher energy the experimental situation is still not settled.
[1] V.D. Efros, W. Leidemann, and G. Orlandini, Phys. Rev. Lett. 78, 4015 (1997).
[2] N. Barnea, W. Leidemann and G. Orlandini, Phys. Rev. C 61, 054001 (2000); Nucl. Phys. A693, 565 (2001).