Precision Comparison of Inelastic electron and Positron Scattering from Hydrogen

Fancher, D.L. ; Caldwell, David O. ; Cumalat, John P. ; et al.
Phys.Rev.Lett. 37 (1976) 1323, 1976.
Inspire Record 4108 DOI 10.17182/hepdata.21910

Using 13.5-GeV beams at Stanford Linear Accelerator Center, we have compared electron and positron inelastic scattering over the range 1.2<|q2|<3.3 (GeV/c)2, 2<ν<9.5 GeV for the four-momentum and energy transfers, respectively. We find the ratio of the cross sections to be e+e−=1.0027±0.0035 (including statistical and systematic effects), with no significant dependence on q2 or ν. This result has appreciably smaller errors than previous attempts to find two-photon-exchange effects in electron or muon scattering.

1 data table

No description provided.


Electroproduction of pions near the $\Delta(1236)$ isobar and the form-factor $G^*_M(q^2)$ of the $({\gamma} N\Delta)$ vertex

Bartel, W. ; Dudelzak, B. ; Krehbiel, H. ; et al.
Phys.Lett.B 28 (1968) 148-151, 1968.
Inspire Record 52791 DOI 10.17182/hepdata.45279

The cross section for inelastic electron-proton scattering was measured at incident electron energies of 1.5 to 6 GeV by magnetic analysis of the scattered electrons at angles between 10° and 35°. For invariant masses of the hardonic final state W ⩽ 1.4 GeV. the measured spectra are compared with theoretical predictions for electroproduction of the Δ(1236) isobar. The magnetic dipole transition form factor G ∗ M ( q 2 ) of the (γ N Δ)-vertex is derived for momentum transfers q 2 = 0.2 − 2.34 (GeV/ c ) 2 ard found to decrease more rapidly with q 2 than the proton form factors.

1 data table

Axis error includes +- 0.0/0.0 contribution.