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Title: Q2 Dependence of Quadrupole Strength in the gamma*p-->Delta+(1232) --> p pi0 Transition

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 Q{sup 2} dependence of the magnetic (M{sub 1+}), electric (E{sub 1+}), and scalar (S{sub 1+}) multipoles in the {gamma}*p {yields} {Delta}{sup +}(1232) {yields} p{pi}{sup 0} transition. New precision measurements of the ratios E{sub 1+}/M{sub 1+} and S{sub 1+}/M{sub 1+} are reported here over the range Q{sup 2} = 0.4-1.8 GeV{sup 2}. Results are best described by recent unitary models in which the pion cloud plays a dominant role.

Authors:
; ; ;
Publication Date:
Research Org.:
Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States)
Sponsoring Org.:
USDOE Office of Energy Research (ER) (US)
OSTI Identifier:
838763
Report Number(s):
JLAB-PHY-01-89; DOE/ER/40150-4987; hep-ex/0110007
Journal ID: ISSN 0031-9007; PRLTAO; TRN: US0501526
DOE Contract Number:  
AC05-84ER40150
Resource Type:
Journal Article
Journal Name:
Physical Review Letters
Additional Journal Information:
Journal Volume: 88; Journal Issue: 3; Other Information: PBD: 6 Mar 2002; Journal ID: ISSN 0031-9007
Country of Publication:
United States
Language:
English
Subject:
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; ACCURACY; BARYONS; CLOUDS; DEFORMATION; DEGREES OF FREEDOM; MULTIPOLES; NUCLEONS; PIONS; QUADRUPOLES; QUARKS; SCALARS; SENSITIVITY; TENSOR FORCES

Citation Formats

Burkert, Volker, Joo, Kyungseon, Smith, Lee, Minehart, Ralph, and et. Al. Q2 Dependence of Quadrupole Strength in the gamma*p-->Delta+(1232) --> p pi0 Transition. United States: N. p., 2002. Web.
Burkert, Volker, Joo, Kyungseon, Smith, Lee, Minehart, Ralph, & et. Al. Q2 Dependence of Quadrupole Strength in the gamma*p-->Delta+(1232) --> p pi0 Transition. United States.
Burkert, Volker, Joo, Kyungseon, Smith, Lee, Minehart, Ralph, and et. Al. 2002. "Q2 Dependence of Quadrupole Strength in the gamma*p-->Delta+(1232) --> p pi0 Transition". United States. https://www.osti.gov/servlets/purl/838763.
@article{osti_838763,
title = {Q2 Dependence of Quadrupole Strength in the gamma*p-->Delta+(1232) --> p pi0 Transition},
author = {Burkert, Volker and Joo, Kyungseon and Smith, Lee and Minehart, Ralph and et. Al.},
abstractNote = {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 Q{sup 2} dependence of the magnetic (M{sub 1+}), electric (E{sub 1+}), and scalar (S{sub 1+}) multipoles in the {gamma}*p {yields} {Delta}{sup +}(1232) {yields} p{pi}{sup 0} transition. New precision measurements of the ratios E{sub 1+}/M{sub 1+} and S{sub 1+}/M{sub 1+} are reported here over the range Q{sup 2} = 0.4-1.8 GeV{sup 2}. Results are best described by recent unitary models in which the pion cloud plays a dominant role.},
doi = {},
url = {https://www.osti.gov/biblio/838763}, journal = {Physical Review Letters},
issn = {0031-9007},
number = 3,
volume = 88,
place = {United States},
year = {Wed Mar 06 00:00:00 EST 2002},
month = {Wed Mar 06 00:00:00 EST 2002}
}