Proton ground-state correlations in 40Ca studied with the reaction 40Ca(e, e′ p)49K

Kramer, G. J.; Blok, H.P.; Brand, van den J.F.J.; Bulten, H.; Ent, R.; Jans, E.; Lanen, J.B.J.M.; Lapikás, L.; Nann, H.; Quint, E.N.M.; Steenhoven, van der G; Huberts, de Pka Peter Witt; Wagner, G.

doi:10.1016/s0370-2693(89)80022-x

Cited by 86 publications

(72 citation statements)

References 19 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Our current results are also larger by about 10-15% than the numbers extracted in Ref. [26]. Introducing local DOM potentials in the analysis of transfer reactions has been shown to have salutary effects for the extraction of spectroscopic information of neutrons [31] and nonlocal potentials should further improve such analyses.…”

contrasting

confidence: 53%

“…We merely aimed for a reasonable representation of these cross sections since their interpretation requires further consideration of rescattering contributions [25]. We did not include the results of the analysis of the (e, e ′ p) reaction from NIKHEF [26] because the extracted spectroscopic factors depend on the employed local optical potentials. We plan to reanalyze these data with our nonlocal potentials in a future study.…”

mentioning

confidence: 99%

See 1 more Smart Citation

Forging the Link between Nuclear Reactions and Nuclear Structure

et al. 2014

View full text Add to dashboard Cite

A comprehensive description of all single-particle properties associated with the nucleus 40 Ca is generated by employing a nonlocal dispersive optical potential capable of simultaneously reproducing all relevant data above and below the Fermi energy. The introduction of nonlocality in the absorptive potentials yields equivalent elastic differential cross sections as compared to local versions but changes the absorption profile as a function of angular momentum suggesting important consequences for the analysis of nuclear reactions. Below the Fermi energy, nonlocality is essential to allow for an accurate representation of particle number and the nuclear charge density. Spectral properties implied by (e, e ′ p) and (p, 2p) reactions are correctly incorporated, including the energy distribution of about 10% high-momentum nucleons, as experimentally determined by data from Jefferson Lab. These high-momentum nucleons provide a substantial contribution to the energy of the ground state, indicating a residual attractive contribution from higher-body interactions for 40 Ca of about 0.64 MeV/A.PACS numbers: 21.10. Pc,24.10.Ht,11.55.Fv The properties of a nucleon that is strongly influenced by the presence of other nucleons have traditionally been studied in separate energy domains. Positive energy nucleons are described by fitted optical potentials mostly in local form [1,2]. Bound nucleons have been analyzed in static potentials that lead to an independent-particle model modified by the interaction between valence nucleons as in traditional shell-model calculations [3,4]. The link between nuclear reactions and nuclear structure is provided by considering these potentials as representing different energy domains of one underlying nucleon self-energy. This idea was implemented in the dispersive optical model (DOM) by Mahaux and Sartor [5]. By employing dispersion relations, the method provides a critical link between the physics above and below the Fermi energy with both sides being influenced by the absorptive potentials on the other side.The DOM provides an ideal strategy to predict properties for exotic nuclei by utilizing extrapolations of these potentials towards the respective drip lines [6,7]. The main stumbling block so far has been the need to utilize the approximate expressions for the properties of nucleons below the Fermi energy that were developed by Mahaux and Sartor [5] to correct for the normalizationdistorting energy dependence of the Hartree-Fock (HF) potential. By restoring the proper treatment of nonlocality in the HF contribution, it was possible to overcome this problem [8] although the local treatment of the absorptive potentials yielded a poor description of the nuclear charge density and particle number.In the present work we have for the first time treated the nonlocality of these potentials for the nucleus 40 Ca with the aim to include all available data below the Fermi energy that can be linked to the nucleon single-particle propagator [9] while maintaining a correct description of the el...

show abstract

contrasting

confidence: 53%

mentioning

confidence: 99%

Forging the Link between Nuclear Reactions and Nuclear Structure

et al. 2014

View full text Add to dashboard Cite

show abstract

“…In Section 3 it is investigated, which part of the bound-state wave function (BSWF) is probed by the (e,e ′ p) and (d, 3 He) reactions, in order to understand the model sensitivity arising from the shape of the BSWF. In Section 4 one 48 Ca(e,e ′ p) [13] and two 48 Ca(d, 3 He) [15,16] data sets are used for a detailed comparison between the (e,e ′ p) and (d, 3 He) spectroscopic factors. In Section 5 a re-analysis of (d, 3 He) data sets for other nuclei is made, in which non-locality and finite range corrections are included and BSWF's deduced from (e,e ′ p) experiments are used.…”

Section: Introductionmentioning

confidence: 99%

A consistent analysis of (e,e′p) and (d,3He) experiments

Kramer¹,

Blok²,

Lapikás³

2001

Nuclear Physics A

Self Cite

203

242

View full text Add to dashboard Cite

The apparent discrepancy between spectroscopic factors obtained in (e,e ′ p) and (d, 3 He) experiments is investigated. This is performed first for 48 Ca(e,e ′ p) and 48 Ca(d, 3 He) experiments and then for other nuclei. It is shown that the discrepancy disappears if the (d, 3 He) experiments are re-analyzed with a non-local finite range DWBA analysis with a bound-state wave function that is obtained from (e,e ′ p) experiments.Key words: NUCLEAR REACTIONS 48 Ca(e,e ′ p), E = 440 MeV; measured ρ(E m , p m ); deduced spectroscopic factors; comparison of spectroscopic factors from (e,e ′ p) and (d, 3 He).

show abstract

“…For the 0d 5/2 , 1s 1/2 , and 0d 3/2 proton holes states, the mean level energies, r.m.s. radii, spectroscopic factors, and widths inferred from measured (e, e ′ p) cross sections [22,23] were also included. Lastly, the fits considered the mean energies of the 0f 7/2 and 0f 5/2 (for 48 Ca only) particle levels [24].…”

mentioning

confidence: 99%

Asymmetry Dependence of Proton Correlations

2006

View full text Add to dashboard Cite

A dispersive optical model analysis of p+ 40 Ca and p+ 48 Ca interactions has been carried out. The real and imaginary potentials have been constrained from fits to elastic scattering data, reaction cross sections, and level properties of valence hole states deduced from (e, e ′ p) data. The surface imaginary potential was found to be larger overall and the gap in this potential on either side of the Fermi energy was found to be smaller for the neutron-rich p+ 48 Ca system. These results imply that protons with energies near the Fermi surface experience larger correlations with increasing asymmetry.PACS numbers: 21.10. Pc,24.10.Ht,11.55.Fv In the independent-particle model, nucleons in the nucleus move in a mean-field potential generated by the other nucleons. All nucleon levels up until the Fermi energy (E F ) are fully occupied, while those above are empty. Although this model enables an understanding of various aspects of nuclear structure, a full description of nuclei and nuclear matter requires consideration of the correlations between the nucleons. These include short-range, central and tensor interactions and longer range correlations associated with low-lying collective excitations [2]. As a result, for closed-shell nuclei, singleparticle (sp) levels below E F have an occupancy of only 70-80% and the levels at higher energy have a nonzero occupancy [3]. The strength of the sp levels are spread over energy, with narrow peaks or broad distributions (depending on their separation from E F ). In addition, there is strength at very high momentum [4].Although there are numerous studies of the effect of correlations on the properties of sp levels for nuclei near stability, there are only a few studies for very neutron or proton-rich nuclei. From neutron knock-out reactions, Gade et al. [5] infer the occupancy of the 0d 5/2 neutron hole state in the proton-rich 32 Ar nucleus is considerably reduced relative to those for stable nuclei.An alternate method to study sp strength is through the use of the dispersive optical model (DOM) developed by Mahaux and Sartor [6]. This description employs the Kramers-Kronig dispersion relation that links the imaginary and real parts of the nucleon self-energy [7]. This procedure links optical-model (OM) analyses of reaction data at positive energies to structural information at negative energies. In the present work, the properties of proton levels in Ca nuclei as a function of asymmetry δ= N −Z A are investigated with the DOM. Previously measured elastic-scattering and reaction-cross-section data for protons on 40 Ca and 48 Ca as well as level properties of hole states in these nuclei, inferred from (e, e ′ p) reactions, were simultaneously fit. The dependence on δ is extracted and used to predict level properties of 60 Ca.In the DOM, the complex energy-dependent potential felt by the protons is comprised of a real V, volume W v and surface W s imaginary components, plus spin-orbit V so and Coulomb V c potentials,are used. The real part of the nuclear potential is assumed...

show abstract

Proton ground-state correlations in 40Ca studied with the reaction 40Ca(e, e′ p)49K

Cited by 86 publications

References 19 publications

Forging the Link between Nuclear Reactions and Nuclear Structure

Forging the Link between Nuclear Reactions and Nuclear Structure

A consistent analysis of (e,e′p) and (d,3He) experiments

Asymmetry Dependence of Proton Correlations

Contact Info

Product

Resources

About