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Q^2 Dependence of Quadrupole Strength in the \gamma*p -> Delta^+(1232) -> p\pi^0 transition

Fissum, Kevin LU orcid (2002) In Physical Review Letters 88. p.122001-122001
Abstract
Models of baryon structure predict a small quadrupole deformation of the nucleon due to residual tensor forces between quarks or distortions from the pion cloud. Sensitivity to quark versus pion degrees of freedom occurs through the Q2 dependence of the magnetic (M1+), electric (E1+), and scalar (S1+) multipoles in the γ∗p→Δ+→pπ0 transition. We report new experimental values for the ratios E1+/M1+ and S1+/M1+ over the range Q2=0.4–1.8GeV2, extracted from precision p(e,e′p)π0 data using a truncated multipole expansion. Results are best described by recent unitary models in which the pion cloud plays a dominant role.
Please use this url to cite or link to this publication:
author
author collaboration
organization
publishing date
type
Contribution to journal
publication status
published
in
Physical Review Letters
volume
88
pages
122001 - 122001
publisher
American Physical Society
external identifiers
  • scopus:85038318780
ISSN
1079-7114
DOI
10.1103/PhysRevLett.88.122001
project
Production of Mesons with Electromagnetic Beams
language
English
LU publication?
yes
id
eea4c1e8-e148-4d24-bc5c-cc0600b4a3d9
date added to LUP
2019-06-24 11:21:18
date last changed
2022-01-31 22:23:54
@article{eea4c1e8-e148-4d24-bc5c-cc0600b4a3d9,
  abstract     = {{Models of baryon structure predict a small quadrupole deformation of the nucleon due to residual tensor forces between quarks or distortions from the pion cloud. Sensitivity to quark versus pion degrees of freedom occurs through the Q2 dependence of the magnetic (M1+), electric (E1+), and scalar (S1+) multipoles in the γ∗p→Δ+→pπ0 transition. We report new experimental values for the ratios E1+/M1+ and S1+/M1+ over the range Q2=0.4–1.8GeV2, extracted from precision p(e,e′p)π0 data using a truncated multipole expansion. Results are best described by recent unitary models in which the pion cloud plays a dominant role.}},
  author       = {{Fissum, Kevin}},
  issn         = {{1079-7114}},
  language     = {{eng}},
  pages        = {{122001--122001}},
  publisher    = {{American Physical Society}},
  series       = {{Physical Review Letters}},
  title        = {{Q^2 Dependence of Quadrupole Strength in the \gamma*p -> Delta^+(1232) -> p\pi^0 transition}},
  url          = {{http://dx.doi.org/10.1103/PhysRevLett.88.122001}},
  doi          = {{10.1103/PhysRevLett.88.122001}},
  volume       = {{88}},
  year         = {{2002}},
}