Pion Production without Annihilation in Antiproton-Proton Interactions at 3.6 GeV/c

Dehne, H.C. ; Lohrmann, E. ; Raubold, E. ; et al.
Phys.Rev. 136 (1964) B843-B851, 1964.
Inspire Record 944966 DOI 10.17182/hepdata.528

Interactions of antiprotons were studied at a momentum of 3.6 GeV/c in a hydrogen bubble chamber. Particular attention was paid to single and multiple pion production without annihilation. Cross sections for the various pion-production channels are given. The total cross section for pion production without annihilation and not including strange-particle production is 18.6−3.3+2.4 mb. Single pion production is found to agree with the predictions of the one-pion-exchange model for small values of the four-momentum transfer. Double pion production in the reaction p¯p→pp¯π+π− agrees with the one-pion-exchange model for all values of the four-momentum transfer, if all possible diagrams are taken into account. The main contribution comes from events where a 32−32 pion-nucleon isobar-anti-isobar pair is produced. For these events the Treiman-Yang angular distribution and the decay angular distributions of the isobars are also in agreement with the one-pion-exchange model.

2 data tables

No description provided.

No description provided.


Photoproduction of $\pi^0$ from Hydrogen near the Second Pion-Nucleon Resonance

DeStaebler, H.C. ; Erickson, E.F. ; Hearn, Anthony C. ; et al.
Phys.Rev. 140 (1965) B336-B348, 1965.
Inspire Record 48749 DOI 10.17182/hepdata.26402

Angular distributions for π0 photoproduction from hydrogen at energies between 660 and 800 MeV and proton center-of-mass angles from 0° to 140° have been measured and analyzed. Some variation from a pure d32 state is seen in the resonance region. A possible high-momentum-transfer enhancement of the cross section is discussed.

13 data tables

Axis error includes +- 0.0/0.0 contribution (3 TO 10////).

Axis error includes +- 0.0/0.0 contribution (3 TO 10////).

Axis error includes +- 0.0/0.0 contribution (3 TO 10////).

More…

A COMPARISON OF ELECTRON - PROTON AND POSITRON - PROTON ELASTIC SCATTERING AT FOUR MOMENTUM TRANSFERS UP TO 5.0-GeV/c**2

Mar, J. ; Barish, Barry C. ; Pine, Jerome ; et al.
Phys.Rev.Lett. 21 (1968) 482-484, 1968.
Inspire Record 52726 DOI 10.17182/hepdata.21724

Measurements of the ratio (R) of positron-proton and electron-proton elastic-scattering cross sections have been made, with the square of the four-momentum transfer (q2) equal to 0.20, 0.69, 0.73, 1.54, 2.44, 3.27, 3.79, and 5.00 (GeV/c)2. The measurements, after radiative corrections, are consistent with R=1, with standard errors ranging from ±0.016 to ±0.123. The results give limits for the size of the two-photon effects.

2 data tables

No description provided.

No description provided.


P-P Interactions at 10 GEV/C

Almeida, S.P. ; Rushbrooke, John G. ; Scharenguivel, J.H. ; et al.
Phys.Rev. 174 (1968) 1638-1661, 1968.
Inspire Record 55886 DOI 10.17182/hepdata.5529

About 3700 two-prong and 5600 four-prong events of 10-GeV/c pp interactions in the Saclay 81-cm hydrogen bubble chamber have been measured and analyzed. The reliability of the identification of the different final states has been checked using Monte Carlo-generated events. For the channels accessible to analysis, cross sections and invariant-mass distributions are given. The c.m. angular distributions and the mean values of the transverse momentum for all final-state particles are shown and discussed. Production of Δ++(1236) accounts for about 30% of the cross section σ(pp→pnπ+)=4.1±0.4 mb. About 50% of the cross section σ(pp→ppπ+π−)=2.4±0.2 mb can be accounted for by Δ++ production. Production of nucleon isobars at 1450, 1520, and 1730 MeV and their subsequent decay into pπ+π− are investigated. Their cross sections, t dependences, and branching ratios are determined, using a one-pion-exchange model (OPEM) for calculating the background distributions. The production of resonances decaying into pπ− at 1236, 1500, and 1690 MeV is seen, and cross sections are given. Resonance production in the ppπ+π−π0 and pnπ+π+π− reactions is studied using background curves calculated with a model based on simple parametrizations of the c.m. momentum distributions. The production of nucleon isobars accounts for nearly 100% of these reactions. For the reactions pp→ppω, ppη, and ppf0, the cross sections found are 0.16±0.03, 0.16±0.07, and 0.10±0.04 mb, respectively, corrected for unobserved decay modes. It is shown that most of the gross features of the pion-production reactions can be explained by the OPEM with the form factors of Ferrari and Selleri.

2 data tables

No description provided.

No description provided.


High-Energy Inelastic e p Scattering at 6-Degrees and 10-Degrees

Bloom, Elliott D. ; Coward, D.H. ; DeStaebler, H.C. ; et al.
Phys.Rev.Lett. 23 (1969) 930-934, 1969.
Inspire Record 54874 DOI 10.17182/hepdata.21635

Cross sections for inelastic scattering of electrons from hydrogen were measured for incident energies from 7 to 17 GeV at scattering angles of 6° to 10° covering a range of squared four-momentum transfers up to 7.4 (GeV/c)2. For low center-of-mass energies of the final hadronic system the cross section shows prominent resonances at low momentum transfer and diminishes markedly at higher momentum transfer. For high excitations the cross section shows only a weak momentum-transfer dependence.

9 data tables

Axis error includes +- 0.0/0.0 contribution (?////FROM UNCERTAINTY IN ELECTRON-DETECTION EFFICIENCY).

Axis error includes +- 0.0/0.0 contribution (?////FROM UNCERTAINTY IN ELECTRON-DETECTION EFFICIENCY).

Axis error includes +- 0.0/0.0 contribution (?////FROM UNCERTAINTY IN ELECTRON-DETECTION EFFICIENCY).

More…

Determination of the total photon - proton cross-section from high-energy inelastic electron scattering

Bloom, Elliott D. ; Cottrell, R.Leslie ; Coward, D.H. ; et al.
SLAC-PUB-0653, 1969.
Inspire Record 54903 DOI 10.17182/hepdata.9945

None

11 data tables

No description provided.

No description provided.

No description provided.

More…

MEASUREMENT OF THE RATIO OF THE PROTON FORM-FACTORS, G(E) / G(M), AT HIGH MOMENTUM TRANSFERS AND THE QUESTION OF SCALING

Litt, J. ; Buschhorn, G. ; Coward, D.H. ; et al.
Phys.Lett.B 31 (1970) 40-44, 1970.
Inspire Record 54895 DOI 10.17182/hepdata.28767

Electron-proton elastic scattering cross sections have been measured at the Stanford Linear Accelerator Center at four-momentum transfers squared (q 2 ) of 1.0, 1.5, 2.0, 2.5and 3.75 (GeV/ c ) 2 . The angular distributions at q 2 = 2.5 and 3.75 (GeV/ c ) 2 are sufficient to provide values of the ratio G E / G M independent of the results from other laboratories. Our results are compatible with scaling, G E (q 2 ) = G M (q 2 )/ μ , within the experimental errors.

6 data tables

No description provided.

No description provided.

No description provided.

More…

Measurements of the polarisation of the recoil proton in elastic electron proton scattering at q-squared=1.3, 1.5 and 1.9(gev/c)squared

Kirkman, H.C. ; Railton, R. ; Rutherglen, J.G. ; et al.
Phys.Lett.B 32 (1970) 519-522, 1970.
Inspire Record 63101 DOI 10.17182/hepdata.28765

An experiment has been carried out to determine the imaginary part of the two-photon exchange amplitude by measuring the polarisation of the recoil proton in elastic electron-proton scattering. The polirisation was found to be −0.006 ± 0.030 at q 2 = 1.3 (GeV/ c ) 2 , +0.052 ± 0.55 at 1.5 (GeV/ c ) 2 and +0.065 ± 0.087 at 1.9 (GeV/ c ) 2 .

1 data table

No description provided.


Inelastic electron-Proton Scattering at Large Momentum Transfers

Miller, Guthrie ; Bloom, Elliott D. ; Buschhorn, G. ; et al.
Phys.Rev.D 5 (1972) 528, 1972.
Inspire Record 67123 DOI 10.17182/hepdata.22355

Differential cross sections for electrons scattered inelastically from hydrogen have been measured at 18°, 26°, and 34°. The range of incident energy was 4.5 to 18 GeV, and the range of four-momentum transfer squared was 1.5 to 21 (GeVc)2. With the use of these data in conjunction with previously measured data at 6° and 10°, the contributions from the longitudinal and transverse components of the exchanged photon have been separately determined. The values of the ratio of the photoabsorption cross sections σSσT are found to lie in the range 0 to 0.5. The question of scaling of 2MpW1 and νW2 as a function of ω is discussed, and scaling is verified for a large kinematic range. Also, a new scaling variable which reduces to ω in the Bjorken limit is introduced which extends the scaling region. The behavior of σT and σS is also discussed as a function of ν and q2. Various weighted sum rules of νW2 are evaluated.

18 data tables

Axis error includes +- 0.0/0.0 contribution (0. TO 2.////DUE TO PION CONTAMINATION).

Axis error includes +- 0.0/0.0 contribution (0. TO 2.////DUE TO PION CONTAMINATION).

Axis error includes +- 0.0/0.0 contribution (0. TO 2.////DUE TO PION CONTAMINATION).

More…

Elastic electron - Proton Scattering at Large Four Momentum Transfer

Kirk, Paul N. ; Breidenbach, Martin ; Friedman, Jerome I. ; et al.
Phys.Rev.D 8 (1973) 63-91, 1973.
Inspire Record 73424 DOI 10.17182/hepdata.21999

Electron-proton elastic-scattering cross sections have been measured at the Stanford Linear Accelerator Center for four-momentum transfers squared q 2 from 1.0 to 25.0 (GeVc)2. The electric (GEp) and magnetic (GMp) form factors of the proton were not separated, since angular distributions were not measured at each q 2. However, values for GMp were derived assuming various relations between GEp and GMp. Several theoretical models for the behavior of the proton magnetic form factor at high values of q 2 are compared with the data.

22 data tables

No description provided.

No description provided.

No description provided.

More…