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Backward scattering of positrons and electrons on protons

Bouquet, B. ; Benaksas, D. ; Grossetête, B. ; et al.

Phys.Lett.B 26 (1968) 178-180, 1968.

Inspire Record 1389620 DOI 10.17182/hepdata.29320

The ratio R = σ (e + + p)/ σ (e − + p) of the elastic scattering cross-section detecting the recoil proton at 0 o in coincidence with the backward electron or positron was found to be R = 1.036 ± 0.018 at q 2 = 8 fm −2 , R = 1.079 ± 0.046 at q 2 = 32 fm −2 .

2 data tables

Table 1

Axis error includes +- 0.0/0.0 contribution (?////Errors presented are the total combined statistical and systematic error s. Radiative corrections applied).

Table 2

Axis error includes +- 0.0/0.0 contribution (?////Errors presented are the total combined statistical and systematic error s. Radiative corrections applied).

Omega production by e+ e- annihilation

Benaksas, D. ; Cosme, G. ; Jean-Marie, B. ; et al.

Phys.Lett.B 42 (1972) 507-510, 1972.

Inspire Record 84977 DOI 10.17182/hepdata.28178

A large solid angle detector has been used to observe π + π − π 0 events produced, at the ω energy, by electron-positron collisions in the ORSAY storage ring. From the ω excitation curve we have deduced: σ ( e + e − → ω 3 π ) = (180 ± 0.20) μ b, Γ = (9.1 ± 0.8) MeV and with B( ω → π + π − π 0 ) = 0.898 ± 0.045 we have calculated Γ e + e − = (0.76 ± 0. 08) keV and g 2 ω 4π = 18.4 ± 1.8 .

2 data tables

Table 1

EXPERIMENTAL CROSS SECTION INCLUDING RADIATIVE EFFECTS.

Table 2

FITTED CROSS SECTION AT OMEGA PEAK, RADIATIVELY CORRECTED.

pi+ pi- production by e+ e- annihilation in the rho energy range with the Orsay storage ring

Benaksas, D. ; Cosme, G. ; Jean-Marie, B. ; et al.

Phys.Lett.B 39 (1972) 289-293, 1972.

Inspire Record 73648 DOI 10.17182/hepdata.28321

A large solid angle detector has been used to observe two body events produced by electron-positron collisions in the Orsay storage ring. From the π + π − excitation curve in the ϱ region we have deduced the amplitude and the phase of the ω-ϱ interference, and the ϱ resonance paramaters: M ϱ = (775.4±7.3) MeV, Γ ϱ = (149.6 ± 23.2) MeV, √ B ( ω → π + π − ) = 0.19 ± 0.05, φ = (85.7 ± 15.3) 0 , σ ( e + e − → ϱ ) = (1.00 ± 0.13) μ b at S = M ϱ 2 , B ( ϱ → e + e − = (4.1 ± 0.5) × 10 −5 , Γ ( ϱ → e + e − ) = (6.1 ± 0.7) keV, ( g ϱ 2 /4 π ) = 2.26 ± 0.25, ( g ϱππ 2 /4 π ) = 2.84 ± 0.50.

1 data table

Table 1

STATISTICAL ERRORS ONLY. CROSS SECTION AT RHO0 PEAK IS 1.00 +- 0.13 MUB FROM FIT.

PROTON FORM-FACTORS FROM PROTON OBSERVATION

Frerejacque, Daniel ; Benaksas, David ; Drickey, Darrell James ;

Phys.Rev. 141 (1966) 1308-1312, 1966.

Inspire Record 48595 DOI 10.17182/hepdata.26652

A determination of the electric and magnetic form factors of the proton has been made by studying the elastic scattering of electrons from a polyethylene target by observation of the recoiling proton at 0° and 30° for values of q2 between 1 and 1.8 F−2. From these measurements we have deduced the charge radius Rc and the magnetic radius Rm of the proton and find equality within the experimental errors (Rc=0.800±0.025 F; Rm=0.810±0.029 F).

8 data tables

Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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$\pi^+$ $\pi^-$ production in $e^+$ $e^-$ collisions and $\rho$-$\omega$ interference

Augustin, J.E. ; Benaksas, D. ; Buon, J. ; et al.

(1969) 35, 1969.

Inspire Record 58289 DOI 10.17182/hepdata.37427

None

1 data table

Table 1

RELATIVE PRODUCTION OF PION PAIRS WITHOUT RADIATIVE CORRECTIONS.

Omega-neutral production by e-plus e-minus annihilation

Augustin, J.E. ; Benaksas, D. ; Buon, J. ; et al.

Phys.Lett.B 28 (1969) 513-516, 1969.

Inspire Record 56682 DOI 10.17182/hepdata.29065

The reaction e + e − → ω o has been measured by detecting the charged pions of the π + π − π o decay mode of the ω o. A partial decay width of ω o in e + e − : Γ e + e − =0.94±0.18 keV is deduced from this result.

1 data table

Table 1

FITTED, BACKGROUND SUBTRACTED, PEAK OMEGA CROSS SECTION, CORRECTED FOR UNOBSERVED DECAYS, IS 1.82 +- 0.34 MUB. TABULATED ASSUMING CENTRAL ENERGY IS 782.6 MEV. VACUUM POLARIZATION AND RADIATIVE CORRECTIONS APPLIED.

Deuteron Electromagnetic Form Factors for F-3-2 < q2 < F-6-2

Benaksas, D. ; Drickey, D. ; Frerejacque, D. ;

Phys.Rev. 148 (1966) 1327-1331, 1966.

Inspire Record 944953 DOI 10.17182/hepdata.26653

Two groups of measurements have been made on the elastic scattering of electrons by deuterium; in each case we observed the recoil deuteron instead of the scattered electron. In the first case the spectrometer was set at 45° so that magnetic scattering was unimportant (about 10%) and we deduced the electric form factors of the deuteron. In the second case deuterons were observed at 0°, allowing us to measure directly the magnetic form factor of the deuteron. Form factors of the neutron were deduced from these measurements for the transfer values q2=3, 4, and 5 (F−2). Preliminary results were given in a first paper. Here we also include a description of the experimental setup and discuss relativistic and exchange-current corrections.

3 data tables

Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

Alpha breakup of Li-6 and Li-7 near the Coulomb barrier

Kelly, G. R. ; Davis, N. J. ; Ward, R. P. ; et al.

Phys.Rev.C 63 (2001) 024601, 2001.

Inspire Record 551836 DOI 10.17182/hepdata.25434

Angular distributions of the α-particle production differential cross section from the breakup of 6Li and 7Li projectiles incident on a 208Pb target have been measured at seven projectile energies between 29 and 52 MeV. The α-breakup cross section of 6Li was found to be systematically greater than that of 7Li across the entire energy range. These data have been compared with previously reported results and with the predictions of continuum-discretized coupled channels (CDCC) calculations including resonant and nonresonant projectile breakup. The present data compare well with previous measurements, while the CDCC calculations provide a reasonable prediction of the relative α-breakup cross sections but underpredict their absolute values. The calculations confirm that a major factor in the enhancement of the 6Li to 7Li α-breakup cross section is the difference between the α-breakup thresholds of the two isotopes. These results have implications for structural studies of light exotic nuclei based on elastic scattering.

2 data tables

Table 1

No description provided.

Table 2

No description provided.

Single photoproduction of neutral π-mesons on hydrogen at small angles between 1.3 and 3 GeV

Braunschweig, M. ; Husmann, D. ; Lübelsmeyer, K. ; et al.

Phys.Lett. 22 (1966) 705-708, 1966.

Inspire Record 1389452 DOI 10.17182/hepdata.753

The differential cross section of the reaction γ + p → p + πo has been measured at the Deutsches Elektronen- Synchrotron, Hamburg, at mean phonon energies of 1.36, 2.0 and 3.0 GeV and pion center of mass angles between 0o and 70o. The results are compared with some theoretical calculations based on elementary and reggeized 1- meson exchange.

4 data tables

Table 1

Axis error includes +- 12/12 contribution.

Table 2

Axis error includes +- 12/12 contribution.

Table 3

Axis error includes +- 12/12 contribution.

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