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Title: Valence proton-neutron interactions throughout the mass surface

Authors:
; ;
Publication Date:
Research Org.:
Clark University
Sponsoring Org.:
USDOE Office of Science (SC)
OSTI Identifier:
898325
Report Number(s):
DOE/ER/40417-213
DOE Contract Number:
FG02-88ER40417
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review C; Journal Volume: 73
Country of Publication:
United States
Language:
English
Subject:
73 NUCLEAR PHYSICS AND RADIATION PHYSICS

Citation Formats

D. S. Brenner, R. B. Cakirli, and and R. F. Casten. Valence proton-neutron interactions throughout the mass surface. United States: N. p., 2006. Web. doi:10.1103/PhysRevC.73.034315.
D. S. Brenner, R. B. Cakirli, & and R. F. Casten. Valence proton-neutron interactions throughout the mass surface. United States. doi:10.1103/PhysRevC.73.034315.
D. S. Brenner, R. B. Cakirli, and and R. F. Casten. Tue . "Valence proton-neutron interactions throughout the mass surface". United States. doi:10.1103/PhysRevC.73.034315.
@article{osti_898325,
title = {Valence proton-neutron interactions throughout the mass surface},
author = {D. S. Brenner and R. B. Cakirli and and R. F. Casten},
abstractNote = {},
doi = {10.1103/PhysRevC.73.034315},
journal = {Physical Review C},
number = ,
volume = 73,
place = {United States},
year = {Tue Mar 21 00:00:00 EST 2006},
month = {Tue Mar 21 00:00:00 EST 2006}
}
  • Empirical average proton-neutron interaction energies, {delta}V{sub pn}, between the last nucleons can be isolated using double differences of masses. We have examined the systematic behavior of {delta}V{sub pn} throughout the mass surface using the 2003 mass table that includes many new and improved experimental masses. The results are especially revealing for self-conjugate nuclei and in regions of strong shell closures in heavy nuclei. In the former the large p-n interaction strength can be interpreted as a consequence of the T=0 interaction between protons and neutrons in spatially similar orbitals. In the latter, the bifurcated systematic can be understood in termsmore » of the evolution of proton and neutron orbital overlaps in regions surrounding a shell closure. In regions between shells, anomalies are sometimes encountered that are not fully understood. They might reflect structural effects or could arise from one or more erroneously measured masses. A scheme based on fractional shell filling is presented that may serve as a signature of shell structure in exotic nuclei. A link between empirical p-n interactions and growth rates of collectivity is pointed out. Finally, our analysis is used to identify candidates for future mass measurements and their needed levels of accuracy, many of which will require new exotic beam facilities.« less
  • The low-spin structure of one-proton, one-neutron {sup 210}Bi nucleus was investigated in cold-neutron capture reaction on {sup 209}Bi. The γ-coincidence measurements were performed with use of EXILL array consisted of 16 HPGe detectors. The experimental results were compared to shell-model calculations involving valence particles excitations. The {sup 210}Bi nucleus offers the potential to test the effective proton-neutron interactions because most of the states should arise from the proton-neutron excitations. Additionally, it was discovered that a few states should come from the couplings of valence particles to the 3{sup −} octupole vibration in {sup 208}Pb which provides also the possibility ofmore » testing the calculations involving the core excitations.« less
  • The question of cancellation of the logarithmic divergence appearing in the proton-neutron mass difference is studied in a unified theory of weak and electromagnetic interactions. It is concluded that the contribution from weak hadronic currents in an extension of the Salam-Weinberg model for leptons to hadrons does not cancel the logarithmic divergencence arising from purely elecomagnetic interactions.