Michael, W.
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Angular Distribution of the Target Asymmetry on Polarized Protons for the Reaction gamma p (Polarized) --> pi+ n at a Photon Energy of 700-MeV

Althoff, K.H. ; Conrad, R. ; Gies, M. ; et al.
Phys.Lett.B 63 (1976) 107-110, 1976.
Inspire Record 114330 DOI 10.17182/hepdata.27654

At the Bonn 2.5 GeV electron synchrotron the angular distribution of the target asymmetry T = (σ↑ − σ↓) (σ↑ + σ↓) for the reaction γp↑ → π + n was measured at a mean photon energy of 700 MeV and pion CM-angles from 50° to 155°. The combination of a 3 He-cryostat, polarizing the free protons in the target up to 65%, with a large acceptance magnet for pion detection led to statistical errors of the target asymmetry comparable with those of cross section measurements.

1 data table
Table 1

No description provided.


The Applicability of Zweig's Rule to anti-p p Annihilations at 3.6-GeV/c

Donald, R.A. ; Edwards, D.N. ; Houlden, M. ; et al.
Phys.Lett.B 61 (1976) 210-212, 1976.
Inspire Record 113109 DOI 10.17182/hepdata.27692

The final states øππ and øKK̄ arising from p̄p annihilations at 3.6 GeV/ c have been studied. The results are in agreement with Zweig's rule contrary to what is observed in high energy pp collisions.

1 data table
Table 1

No description provided.


The Polarized Beam Asymmetry in Photoproduction of eta Mesons from Protons at 2.5-GeV and 3.0-GeV

Bussey, P.J. ; Raine, C. ; Rutherglen, J.G. ; et al.
Phys.Lett.B 61 (1976) 479-482, 1976.
Inspire Record 108515 DOI 10.17182/hepdata.27687

Measurements of the polarised beam asymmetry parameter Σ for eta photoproduction from protons, have been carried out at incident energies of 2.5 GeV and 3.0 GeV, and for various t -values between −0.2 (GeV/c) 2 and −1.2 (GeV/c) 2 . The values of Σ are close to +1 for values of | t | less than 0.7 (GeV/c) 2 , showing that there can be little contribution from unnatural parity exchange in any Regge exchange model of the process, in disagreement with present theories. Differential cross sections for the process werre also measured, and are consistent with those from other experiments.

2 data tables
Table 1

No description provided.

Table 2

No description provided.


Study of the Reaction pi+ p --> omega Delta++ (1236) at 16-GeV/c

The Aachen-Berlin-Bonn-CERN-Cracow-Heidelberg collaboration Grassler, H. ; Honecker, R. ; Laven, H. ; et al.
Nucl.Phys.B 115 (1976) 365-384, 1976.
Inspire Record 110390 DOI 10.17182/hepdata.35656

The reaction π + p→ ωΔ ++ (1236) is studied at 16 GeV/ c . Cross section, differential cross section, single and joint spin-density matrix elements are given and the correlations between the ε and Δ ++ (1236) decay angular distributions are investigated. Natural and unnatural spin-parity exchanges contribute to this reaction in roughly equal amounts. Natural exchanges lead predominantly to Δ ++ (1236) with helicity ± 3 2 , while unnatural exchanges lead predominantly to Δ ++ (1236) with helicity ± 1 2 and to ε with helicity zero. Furthermore, unnatural exchanges are small at t ′≅0.2 GeV 2 compared to other t ′ values, which may be due to the nonsense wrong-signature-zero of the B-meson exchange. Quark model relations are found to be satisfied by the data.

6 data tables
Table 1

CORRECTED FOR UNSEEN OMEGA DECAY MODES. 'SLICE METHOD' USED TO HANDLE RESONANCE TAILS AND BACKGROUND.

Table 2

FROM EVENTS WITHIN MASS-CUTS FOR RESONANCES AND NORMALIZED TO TOTAL CROSS SECTION.

Table 3

'ALL'.

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Study of the Reaction pi+ p --> rho0 Delta++ (1236) at 16-GeV/c

The Aachen-Berlin-Bonn-CERN-Cracow-Heidelberg collaboration Honecker, R. ; Lauscher, P. ; Laven, H. ; et al.
Nucl.Phys.B 106 (1976) 365-384, 1976.
Inspire Record 108897 DOI 10.17182/hepdata.35864

The reaction π + p → ϱ 0 Δ ++ (1236) at 16 GeV/ c has been studied. Cross section, differential cross section, single and joint spin-density matrix elements are given. Correlations between the ϱ 0 and Δ ++ (1236) decay distributions are observed. Unnatural spin-parity exchanges, mainly observed at small t ' values, dominate the ϱ 0 Δ ++ (1236) production. The natural exchange contributions are only (7 ± 2)% and become as important as the unnatural exchanges beyond t ' = 0.3 GeV 2 . Contributions to Δ ++ (1236) helicity 3 2 states do not exceed 20% of the total ϱ 0 Δ ++ (1236) cross section and are mainly due to unnatural exchanges.

6 data tables
Table 1

'SLICE METHOD' USED TO HANDLE RESONANCE TAILS AND BACKGROUND.

Table 2

FROM EVENTS WITHIN MASS-CUTS FOR RESONANCES AND NORMALIZED TO TOTAL CROSS SECTION.

More…

Experimental Test for the 1 >= Delta I (Isospin) Rule in Electromagnetic Transitions

Christ, A. ; Noldeke, G. ; Nuding, W. ; et al.
Nucl.Phys.B 102 (1976) 429-438, 1976.
Inspire Record 112957 DOI 10.17182/hepdata.35990

At the Bonn 500 MeV synchrotron the differential cross sections for the photoproduction of neutral pions on protons and neutrons have been measured in a single experiment using a target of liquid deuterium. The final state has been completely determined by measuring the outgoing pion and one nucleon in coincidence. Measurements of the ratio R = π 0 n/ π 0 p have been done at different angles and energies. The possible existence of an isotensor contribution has been limited to (−2 ± 3)% of the isovector amplitude.

1 data table
Table 1

No description provided.


Angular Dependence of the Polarization of the Recoil Proton from the Reaction gamma p --> pi0 p in the Region of the Second Resonance

Blum, P. ; Brinckmann, P. ; Brockmann, R. ; et al.
Z.Phys.A 277 (1976) 311, 1976.
Inspire Record 108242 DOI 10.17182/hepdata.16619

The polarization of the recoil proton from the reactionγp→π0p has been measured for photon energies between 600 and 1,200 MeV and pion c.m. angles between 90° and 150°.

1 data table
Table 1

No description provided.


Angular Dependence of the Polarization of the Recoil Proton from the Reaction gamma p --> pi0 p in the Region of the Third Resonance

Blum, P. ; Brockmann, R. ; Mohr, W. ;
Z.Phys.A 278 (1976) 275, 1976.
Inspire Record 108304 DOI 10.17182/hepdata.16615

The polarization of the recoil proton from the reactionγp→π0p has been measured for photon energies between 900–1,350 MeV and pion c.m. angles between 70° and 150°. There are significant deviations from recent analysis.

3 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.


Observation of a Spin 4 Neutral H Meson with 2-GeV Mass

Apel, W.D. ; Augenstein, K. ; Bertolucci, E. ; et al.
Yad.Fiz. 23 (1976) 333-340, 1976.
Inspire Record 113106 DOI 10.17182/hepdata.19080

None

1 data table
Table 1

No description provided.


Inclusive Single Particle Production at 90-Degrees in the Center-Of-Mass System for Nuclear Targets and 28.5-GeV/c Incident Protons

Becker, U. ; Burger, J. ; Chen, M. ; et al.
Phys.Rev.Lett. 37 (1976) 1731-1734, 1976.
Inspire Record 115394 DOI 10.17182/hepdata.21074

The invariant cross section for the inclusive production of π+, π−, K+, K−, p, and p¯ is presented for proton-nucleon interactions at plab=28.5 GeV/c. Beryllium, titanium, and tungsten targets were used and the yields were extrapolated to A=1 using the power law σ∼Aα. The exponent α increases with pT, except for protons. The pT dependence of the cross sections is compared with a simple fireball model.

2 data tables
Table 1

No description provided.

Table 2

No description provided.