G{sub E{sub p}}/G{sub M{sub p}} Ratio by Polarization Transfer in e(vector sign)p {yields} ep(vector sign)

Journal Article · Mon Feb 14 04:00:00 EST 2000 · Physical Review Letters

DOI:https://doi.org/10.1103/PhysRevLett.84.1398· OSTI ID:20215543

Jones, M K ^[1]; Aniol, K A ^[2]; Baker, F T ^[3]; Berthot, J ^[4]; Bertin, P Y ^[4]; Bertozzi, W ^[5]; Besson, A ^[4]; Bimbot, L ^[6]; Boeglin, W U ^[7]; Brash, E J ^[8]

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1. College of William and Mary, Williamsburg, Virginia 23187 (United States)
2. California State University at Los Angeles, Los Angeles, California 90032 (United States)
3. University of Georgia, Athens, Georgia 30602 (United States)
4. Universite Blaise Pascal/CNRS-IN2P3, F-63177 Aubiere, (France)
5. Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 (United States)
6. Institut de Physique Nucleaire, F-91406 Orsay, (France)
7. Florida International University, Miami, Florida 33199 (United States)
8. University of Regina, Regina, SK S4S OA2, (Canada)

The ratio of the proton's elastic electromagnetic form factors, G{sub E{sub p}}/G{sub M{sub p}} , was obtained by measuring P{sub t} and P{sub l} , the transverse and the longitudinal recoil proton polarization, respectively. For elastic e(vector sign)p{yields}ep(vector sign) , G{sub E{sub p}}/G{sub M{sub p}} is proportional to P{sub t}/P{sub l} . Simultaneous measurement of P{sub t} and P{sub l} in a polarimeter provides good control of the systematic uncertainty. The results for the ratio G{sub E{sub p}}/G{sub M{sub p}} show a systematic decrease as Q{sup 2} increases from 0.5 to 3.5 GeV{sup 2} , indicating for the first time a definite difference in the spatial distribution of charge and magnetization currents in the proton. (c) 2000 The American Physical Society.

• OSTI ID: 20215543
• Journal Information: Physical Review Letters, Journal Name: Physical Review Letters Journal Issue: 7 Vol. 84; ISSN 0031-9007; ISSN PRLTAO
• Country of Publication: United States
• Language: English

Related Subjects

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
ELECTROMAGNETIC FORM FACTORS
ELECTRON-PROTON INTERACTIONS
EXPERIMENTAL DATA
PROTONS