The spectral function of He-4 is calculated with the Lorentz integral transform method in a large energy and momentum range. The excitation spectrum of the residual 3N system is fully taken into account. The obtained spectral function is used to calculate the quasielastic longitudinal (e,e') response R-L Of 4He for q = 300, 400, and 500 MeV/c. Comparison with the exact R-L shows a rather sizable disagreement except in the quasielastic peak, where the differences reduce to about 10% at q=500 MeV/c. It is shown as well that very simple momentum distribution approximations for the spectral function provide almost the same results for R-L as the exact spectral function.
Exact 4 He spectral function in a semirealistic NN potential model
Efros, Victor;Leidemann, Winfried;Orlandini, Giuseppina
1998-01-01
Abstract
The spectral function of He-4 is calculated with the Lorentz integral transform method in a large energy and momentum range. The excitation spectrum of the residual 3N system is fully taken into account. The obtained spectral function is used to calculate the quasielastic longitudinal (e,e') response R-L Of 4He for q = 300, 400, and 500 MeV/c. Comparison with the exact R-L shows a rather sizable disagreement except in the quasielastic peak, where the differences reduce to about 10% at q=500 MeV/c. It is shown as well that very simple momentum distribution approximations for the spectral function provide almost the same results for R-L as the exact spectral function.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione
