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Electromagnetic form-factors of the proton at squared four momentum transfers between 10-fm-2 and 50 fm-2

Berger, C ; Burkert, V. ; Knop, G. ; et al.

Phys.Lett.B 35 (1971) 87-89, 1971.

Inspire Record 69362 DOI 10.17182/hepdata.28478

Electron-proton elastic scattering cross sections have been measured to determine the proton electromagnetic form factors at squared four-momentum transfers q 2 between 10 and 50 fm −2 . At these values of q 2 we measured angular distributions between 25° and 110° and in addition at 25° and 35° cross sections for q 2 from 2 to 20 fm −2 using the external electron beam of the Bonn 2.5 GeV electron synchrotron. Our results confirm deviations from the scaling law.

15 data tables

Table 1

Axis error includes +- 2/2 contribution (NORMALIZATION ERROR).

Table 2

Axis error includes +- 2/2 contribution (NORMALIZATION ERROR).

Table 3

Axis error includes +- 2/2 contribution (NORMALIZATION ERROR).

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Measurement of proton and neutron electromagnetic form-factors at squared four momentum transfers up to 3-GeV/c$^2$

Bartel, W. ; Busser, F.W. ; Dix, W.r. ; et al.

Nucl.Phys.B 58 (1973) 429-475, 1973.

Inspire Record 83685 DOI 10.17182/hepdata.69173

Electron-proton elastic scattering cross sections have been measured at squared four-momentum transfers q 2 of 0.67, 1.00, 1.17, 1.50, 1.75, 2.33 and 3.00 (GeV/ c ) 2 and Electron scattering angles θ e between 10° and 20° and at about 86° in the laboratory. The proton electromagnetic form factors G E p and G M p were determined. The results indicate that G E p ( q 2 ) decreases faster with increasing q 2 than G M p ( q 2 ). Quasi-elastic electron-deuteron cross sections have been determined at values of q 2 = 0.39, 0.565, 0.78, 1.0 and 1.5 (GeV/ c ) 2 and scattering angles between 10° and 12°. At q 2 = 0.565 (GeV/ c 2 data have also been taken with θ e = 35° and at q 2 = 1.0 and 1.5 (GeV/ c ) 2 with θ e = 86°. Electron-proton as well as electron-neutron scattering cross sections have been deduced by the ratio method. The theoretical uncertainties of this procedure are shown to be small by comparison of the bound with the free proton cross sections. The magnetic form factor of the neutron G M n derived from the data is consistent with the scaling law. The charge form factor of the neutron is found to be small.

14 data tables

Table 1

Axis error includes +- 2.1/2.1 contribution (NORMALISATION ERROR).

Table 2

Axis error includes +- 2.1/2.1 contribution (NORMALISATION ERROR).

Table 3

Axis error includes +- 2.1/2.1 contribution (NORMALISATION ERROR).

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Measurements of the Deuteron and Proton Magnetic Form-factors at Large Momentum Transfers

Bosted, Peter E. ; Katramatou, A.T. ; Arnold, R.G. ; et al.

Phys.Rev.C 42 (1990) 38-64, 1990.

Inspire Record 283632 DOI 10.17182/hepdata.26165

Measurements of the deuteron elastic magnetic structure function B(Q2) are reported at squared four-momentum transfer values 1.20≤Q2≤2.77 (GeV/c)2. Also reported are values for the proton magnetic form factor GMp(Q2) at 11 Q2 values between 0.49 and 1.75 (GeV/c)2. The data were obtained using an electron beam of 0.5 to 1.3 GeV. Electrons backscattered near 180° were detected in coincidence with deuterons or protons recoiling near 0° in a large solid-angle double-arm spectrometer system. The data for B(Q2) are found to decrease rapidly from Q2=1.2 to 2 (GeV/c)2, and then rise to a secondary maximum around Q2=2.5 (GeV/c)2. Reasonable agreement is found with several different models, including those in the relativistic impulse approximation, nonrelativistic calculations that include meson-exchange currents, isobar configurations, and six-quark configurations, and one calculation based on the Skyrme model. All calculations are very sensitive to the choice of deuteron wave function and nucleon form factor parametrization. The data for GMp(Q2) are in good agreement with the empirical dipole fit.

2 data tables

Table 1

The measured cross section have been devided by those obtained using the dipole form for the proton form factors: G_E=1/(1+Q2/0.71)**2, G_E(Q2)=G_M(Q2)/mu,where Q2 in GeV2, mu=2.79.

Table 2

Axis error includes +- 0.0/0.0 contribution (?////Errors given are the statistical errors and systematic uncertainties add ed in quadreture).

ELECTROPRODUCTION OF PI DELTA AND OTHER NONDIFFRACTIVE FINAL STATES

Day, C.T. ; Harding, D.J. ; Klinger, J.S. ; et al.

Phys.Rev.D 23 (1981) 576-586, 1981.

Inspire Record 166699 DOI 10.17182/hepdata.24078

This paper reports the results of an experiment measuring the parameters of various electroproduction reactions for a range in the electroproduction variables 0.7<Q2<4 GeV2 and 2<W2<16 GeV2. This report is limited to nondiffractive exclusive channels, with detailed results regarding the πΔ final states, statistically limited results for KΛ final states, and upper limits on the production of a number of event topologies containing a single unseen neutral particle.

16 data tables

Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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Omega-Meson Production by Virtual Photons

Joos, P. ; Ladage, A. ; Meyer, H. ; et al.

Nucl.Phys.B 122 (1977) 365-382, 1977.

Inspire Record 118808 DOI 10.17182/hepdata.35453

Qausi-elastic ω production by ep scattering in the kinematic region 0.3. < Q 2 < 1.4 GeV 2 and 1.7 < W < 2.8 GeV was studied using a streamer chamber at DESY. The production angular distribution for γ V p → ω p has a strong non-peripheral component for W < 2 GeV. The ω production cross section falls by a factor of 4 as W changes from 1.7 to 2.8 GeV. In contrast the cross section for ω production with | t | < 0.5 GeV 2 is W independent between 1.7 and 2.8 GeV and for W > 2.0 GeV consistent in both W and Q 2 dependence with the predictions of a model based on one-pion exchange and diffraction.

5 data tables

Table 1

FOR ALL T-VALUES. THE GAMMA* P TOTAL CROSS SECTION WAS TAKEN FROM A FIT TO THE DATA OF S. STEIN ET AL., PR D12, 1884 (1975). 'PPD'.

Table 2

'PPD'. PERIPHERAL OMEGA PRODUCTION.

Table 3

No description provided.

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Electron-Proton Scattering at High-Momentum Transfer

Berkelman, K. ; Feldman, M. ; Littauer, R.M. ; et al.

Phys.Rev. 130 (1963) 2061-2068, 1963.

Inspire Record 46839 DOI 10.17182/hepdata.26788

The elastic electron-proton scattering cross section has been measured at laboratory angles between 90° and 144° and for values of the four-momentum transfer squared between 25 and 45 F−2 (incident electron laboratory energies from 830 to 1360 MeV). Both the scattered electrons and the recoil protons were momentum analyzed and counted in coincidence, making possible background-free measurements down to cross sections of the order of 10−35 cm2/sr. The data are consistent with the Rosenbluth formula, and the resulting form factors tie on well with previous measurements at lower momentum transfer, continuing the established trend.

6 data tables

Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.