Extracting the spectral function of4Hefrom a relativistic plane-wave treatment

Abstract

The spectral function of 4 He is extracted from a plane-wave approximation to the (e, e ′ p) reaction using a fully relativistic formalism. We take advantage of both an algebraic "trick" and a general relativistic formalism for quasifree processes developed earlier to arrive at transparent, analytical expressions for all quasifree (e, e ′ p) observables. An observable is identified for the clean and model-independent extraction of the spectral function. Our simple relativistic plane-wave calculations provide baseline predictions for the recently measured, but not yet fully analyzed, momentum distribution of 4 He by the A1-collaboration from Mainz. Yet in spite of its simplicity, our approach predicts momentum distributions for 4 He that rival some of the best nonrelativistic calculations to date. Finally, we highlight some of the challenges and opportunities that remain, both theoretically and experimentally, in the extraction of quasifree observables. PACS number(s): 25.30.Fj,24.10.Jv,21.10.Jx

Quasifree Processes From Nuclei: Meson Photoproduction and Electron Scattering

“…Faced by an increasing demand for studying quasifree processes from nuclei, we have developed a general fully relativistic treatment for studying such interactions 1,2,3 . The power of the theoretical approach employed here lies in its simplicity.…”

“…We have applied this formalism to two kinds of processes: kaon photoproduction 1,2 and electron scattering 3 . Further, there is a promising potential of applying it to many processes being studied experimentally at various laboratories.…”