High-Momentum-Transfer Electron Scattering fromPb208

Self-consistent Green's function method for nuclei and nuclear matter

“…Putting together all the above considerations, the resulting approximation to the Faddeev equations (152) can be rewritten in a way where all the propagators involved depend only on one energy variable (or two time variables). The forward-going part of this expansion can be written as follows (after Fourier transformation to the energy representation) (155), G 0 > is the forward-going part of the 2p1h propagator for three dressed but noninteracting lines.…”

“…We recall that elastic electron scattering from 208 Pb [152] accurately determines the value of the central charge density in this nucleus. By multiplying this number by A/Z one obtains the relevant central density of heavy nuclei, corresponding to 0.16 nucleons/fm 3 or k F = 1.33 fm −1 .…”

Measurement of the Neutron Radius ofPb208through Parity Violation in Electron Scattering

“…The result A PV ¼ 0:656 AE 0:060ðstatÞ AE 0:014ðsystÞ ppm corresponds to a difference between the radii of the neutron and proton distributions R n À R p ¼ 0:33 þ0:16 À0:18 fm and provides the first electroweak observation of the neutron skin which is expected in a heavy, neutron-rich nucleus. DOI Nuclear charge densities have been accurately measured with electron scattering and have become our picture of the atomic nucleus, see for example [1]. In contrast, our knowledge of neutron densities comes primarily from hadron scattering experiments involving, for example, pions [2], protons [3][4][5], or antiprotons [6,7], the interpretation of which requires a model-dependent description of the nonperturbative strong interaction.…”

“…Assuming a point-proton radius of 5.45 fm [41], corresponding to the measured charge radius of 5.50 fm [1], implies that the neutron distribution is 1:8 larger than that of the protons: R n À R p ¼ 0:33 þ0:16 À0:18 fm [39] (see also [42]). A future run is planned which will reduce the quoted uncertainty by a factor of 3 [43], to discriminate between models and allow predictions relevant for the description of neutron stars and parity violation in atomic systems.…”

“…Here G p E (G n E ) is the Fourier transform of the proton (neutron) electric form factor. The Dirac equation was solved [9] for an electron scattering from w and the experimental ch [1], and the resulting A PV ð Þ integrated over the acceptance, Eq. (3), to yield the open circles in Fig.…”