Electromagnetic response functions of few-nucleon systems

Abstract

Inclusive electromagnetic reactions in few-nucleon systems are studied basing on accurate three- and four-body calculations. The longitudinal 4He(e,e') response function obtained at q\le 600 MeV/c completely agrees with experiment. The exact 4He spectral function obtained in a semirealistic potential model is presented, and the accuracy of the quasielastic response calculated with its help is assessed, as well as the accuracy of some simpler approximations for the response. The photodisintegration cross section of 3He obtained with the realistic AV14 NN force plus UrbanaVIII NNN force agrees with experiment. It is shown that this cross section is very sensitive to underlying nuclear dynamics in the E_\gamma\simeq 70-100 MeV region. In particular, the NNN nuclear force clearly manifests itself in this region.Comment: 10 pages, Latex, style file is included, 7 ps figures, to appear in Proc. of the 2nd Int. Conf. on Perspectives in Hadronic Physics, ITCP, Triest, May 1999, World Sci., Singapor

The Lorentz integral transform (LIT) method and its applications to perturbation-induced reactions

“…Only short summaries of this approach have been published in [9,10]. Overviews of the LIT method and of its applications have been presented at various conferences [11,12] …”

“…For convenience we define them as 10) where E 0 is the ground-state energy, and σ I = 0, so that K(σ, E) is actually a Lorentzian function centered on E 0 + σ R , having σ I as a halfwidth…”

“…In view of equations (5.3) and (5.4) it is evident that the harmonic oscillator (HO) Hamiltonian may be written in the form 10) whereη j = η j /r 0 ,ρ = ρ/r 0 where r 0 = ( /(mω)) 1/2 is the oscillator length. It has the eigenvectors…”

“…The present work constitutes the first comprehensive review article of the LIT method. Only short summaries of this approach have been published in [9,10]. Overviews of the LIT method and of its applications have been presented at various conferences [11,12] 1.…”