Lefrancois, J.
Electron production
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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
Table 1

Axis error includes +- 0.0/0.0 contribution.


Photoproduction of eta meson between threshold and 900 mev

Delcourt, B. ; Lefrancois, J. ; Perez-Y-Jorba, J.P. ; et al.
Phys.Lett.B 29 (1969) 75-78, 1969.
Inspire Record 56793 DOI 10.17182/hepdata.28963

We have measured differential cross sections of γ + p → p + η 0 at several energies. The angular distributions show that S 11 production is predominant in the energy range investigated and that the other resonant terms seen in π-production of η are absent or very low. Finally, experimental data are theoretically interpreted and the S 11 parameters deduced.

6 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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Electromagnetic proton form-factors at squared four momentum transfers between 1-GeV/c**2 and 3-GeV/c**2

Bartel, W. ; Busser, F.W. ; Dix, W.R. ; et al.
Phys.Lett.B 33 (1970) 245-248, 1970.
Inspire Record 63047 DOI 10.17182/hepdata.45284

Electron-proton elastic scattering cross sections have been measured at four-momentum transfers between 1.0 and 3.0 (GeV/ c ) 2 and at electron scattering angles between 10° and 20° and at about 86° in the laboratory. The proton electromagnetic form factors G E and G M were determined. The results indicate that G E ( q 2 ) decreases faster with increasing q 2 than G M ( q 2 ).

2 data tables
Table 1

Axis error includes +- 2.5/2.5 contribution (Due to counting statisticss, separation of elastic events, beam monitoring, incident energy, scattering angle, proton absorption, solid angle, target length and density).

Table 2

CONST(NAME=MU) is the magnetic moment.


Evidence for decays of the d- and e-mesons into delta pi in anti-p p annihilation at 700 mev/c

Defoix, C. ; Do Nascimento, A. ; O' Neall, J.S. ; et al.
Nucl.Phys.B 44 (1972) 125-141, 1972.
Inspire Record 75085 DOI 10.17182/hepdata.32849

A study is made of η 0 production in p p → 3π + 3π − π 0 (7500 events) at an incident momentum of 720 MeV/ c . The reaction is dominated by production of ω 0 (≈68 o/o). The η o production has been studied by means of two independent methods: the first, a study of correlations between the (4 π ) ± and (5 π ) 0 and the (3 π ) 0 systems, circumvents the problem of ω 0 reflections. The second attempts to isolate the η 0 4π channel by means of rigorous selections using the decay properties of η 0 and ω 0 . The results of the two methods are consistent and confirnm the production of σ +- , D 0 and E 0 with the decays ifD 0 → σ ± π ± → η 0 π + π ( su −), E 0 → σ ± π ∓ → η ( su 0) π + π − , E 0 → η 0 π + π − .

1 data table
Table 1

CORRECTED FOR UNOBSERVED ETA DECAYS AND I=0 ASSUMED FOR ETAPRIME, D(1285) AND E(1420) --> ETA PI0 PI0.


The reaction k- p ---> lambda eta from 0.80 to 1.84 gev/c

Rader, R. ; Barloutaud, R. ; Griselin, J. ; et al.
Nuovo Cim.A 16 (1973) 178-186, 1973.
Inspire Record 86997 DOI 10.17182/hepdata.37772

We present new data on the reaction K−p→Λη from 0.80 to 1.84 GeV/c. An interpretation is attempted in terms of the formation of known hyperon resonances.

3 data tables
Table 1

THE ORIGINAL DATA AT 49 MOMENTA HAVE BEEN GROUPED INTO 27 MOMENTUM BANDS. SIG = 4*PI*(REDUCED CM K- WAVELENGTH)**2*LEG(L=0).

Table 2

DATA FURTHER GROUPED INTO 9 MOMENTUM REGIONS.

Table 3

DATA FURTHER GROUPED INTO 9 MOMENTUM REGIONS.


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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Pi0 electroproduction at the delta(1236) resonance at a four-momentum transfer of q-squared = 0.3(gev/c)-squared

Baetzner, K. ; Beck, U. ; Becks, K.H. ; et al.
Nucl.Phys.B 76 (1974) 1-14, 1974.
Inspire Record 94609 DOI 10.17182/hepdata.32274

The reaction e − + p → e − + p + π 0 has been studied in the region of the Δ (1236) resonance at a four-momentum transfer of the virtual photon of 0.3 (GeV/ c ) 2 . Angles and momenta of the secondary electron and of the outgoing proton were measured in coincidence to obtain the angular dependence of the differential cross section. The angular distribution for s- and p-waves of the pion in the πN cm-system was fitted to the cross section for three W -bins around the maximum of the resonance. The contribution of the resonant multipoles M 1+ , E 1+ and S 1+ to the cross section as well as the contribution of the background amplitudes M 1− , E 0+ and S 0+ are given.

3 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.


Cross-sections for quasi-two-body reactions in k- p interactions between 1263 and 1843 mev/c

Berthon, A. ; Tristram, G. ; Vrana, J. ; et al.
Nuovo Cim.A 21 (1974) 146-167, 1974.
Inspire Record 96519 DOI 10.17182/hepdata.37752

We give the cross-sections of quasi-two-body reactions produced in K−-proton interactions at 13 different energies in the centreof-mass energy range 1.915 to 2.168 GeV.

1 data table
Table 1

No description provided.


K- n ---> sigma- eta near threshold

Chu, R.Y.L. ; Bartley, J. ; Dowd, R. ; et al.
Nuovo Cim.A 20 (1974) 35-48, 1974.
Inspire Record 96713 DOI 10.17182/hepdata.37736

The reaction K−n→Σ−η has been studied near threshold. The production angular distribution and the cross-section as a function of energy were measured. The combined angular distributions of this experiment and two previous ones suggest that aJ=1/2 amplitude dominates in Σ−η production. Our cross-section can be fitted with a Σ−1η resonance of mass 1785±12 and width 89±33, or it can be fitted in a zero-effective-range scattering approximation with a scattering length of (0.92±0.12)±i(0.04±0.28) fm.

3 data tables
Table 1

No description provided.

Table 2

CROSS SECTION NEAR THRESHOLD CORRESPONDS TO A SCATTERING LENGTH OF (0.92 +- 0.12) +- I*(0.04 +- 0.28) FM.

Table 3

PRODUCTION ANGULAR DISTRIBUTION - ASSUMED SYMMETRIC IN COS(THETA).


Electroproduction of eta-mesons at the s(11)(1535) resonance

Beck, U. ; Becks, K.H. ; Burkert, V. ; et al.
Phys.Lett.B 51 (1974) 103-105, 1974.
Inspire Record 95168 DOI 10.17182/hepdata.27938

The reaction e − + p → e − + p + η has been studied in the region of the S 11 (1535)-resonance by detecting the recoil proton in coincidence with the scattered electron. The reaction has been observed at three four-momentum transfers of the virtual photon: q 2 = 0.2, 0.28 and 0.4 (GeV/ c ). First results of the differential cross section measurements are given and compared with quark model calculations.

2 data tables
Table 1

No description provided.

Table 2

No description provided.