Determination of the pion form factor up to Q$sup 2$ = 4 GeV$sup 2$ from single-charged-pion electroproduction

Journal Article · Thu Jan 01 04:00:00 EST 1976 · Phys. Rev., D, v. 13, no. 1, pp. 25-42

OSTI ID:4035824

Bebek, C J; Brown, C N; Herzlinger, M; Holmes, S D; Lichtenstein, C A; Pipkin, F M; Raither, S; Sisterson, L K

New measurements of the electroproduction of single charged pions hydrogen and deuterium targets carried out at the Wilson Synchrotron at Cornell University are reported. Measurements were made at the (W, Q$sup 2$) points (2.15 GeV, 1.2 GeV$sup 2$), (2.15, 4.0), and (3.11, 1.2) with hydrogen and deuterium and at (2.15, 2.0), (2.67, 3.4), and (3.11, 1.7) with only hydrogen. The deuterium data were used to determine the ratio of the cross sections for the reactions $gamma$/subV/d $Yields$ $pi$$sup +$nn/subs/ and $gamma$/subV/d $Yields$ $pi$$sup -$pp/subs/ and thus to measure the isoscalar contribution to the reaction $gamma$/subV/p $Yields$ $pi$$sup +$n. The data are consistent with the hypothesis that this ratio is a universal function of the momentum transfer. The measured ratio was used to determine from the hydrogen data and the data taken in earlier experiments the isovector component of the cross section. The dispersion theory formulated by Berends was then used to determine from the isovector component the pion form factor in the Q$sup 2$ range from 0.2 to 4.0 GeV$sup 2$. A simple pole expression of the form 1 + Q$sup 2$/(0.471 +- 0.010)$sup -1$ gives a good fit to the data. (AIP)

• Research Organization: Cyclotron Laboratory, Harvard University, Cambridge, Massachusetts 02138
• NSA Number: NSA-33-024405
• OSTI ID: 4035824
• Journal Information: Phys. Rev., D, v. 13, no. 1, pp. 25-42, Journal Name: Phys. Rev., D, v. 13, no. 1, pp. 25-42; ISSN PRVDA
• Country of Publication: United States
• Language: English

Related Subjects

641001*
DISPERSION RELATIONS
ELECTRON-PROTON INTERACTIONS-- NEUTRONS-- PIONS PLUS
GEV RANGE 10-100
N64110* --Physics (High Energy)--Particle Interactions & Properties (Experimental)--Electromagnetic
PHOTON-DEUTERON INTERACTIONS-- VIRTUAL PARTICLES
VECTOR DOMINANCE MODEL ELECTRON-NEUTRON INTERACTIONS-- PIONS MINUS-- PROTONS