Positive Pion Production by Polarized X Rays between 227 and 373 MeV

Smith, R.C. ; Mozley, R.F. ;
Phys.Rev. 130 (1963) 2429-2440, 1963.
Inspire Record 46842 DOI 10.17182/hepdata.26742

Measurements have been made of the ratio of the π+ photoproduction cross sections at right angles to and along the electric field vector. Data have been taken at 45°, 90°, and 135° at energies of 227, 240, 342, and 373 MeV. A comparison of the data with the predictions of a phenomenological analysis using only S and P waves shows less than 0.1% chance of obtaining such results without the inclusion of higher angular momenta, and hence, demonstrates even more convincingly the need for a meson current term which has been indicated by other measurements. A comparison is made with the relativistic dispersion relations of McKinley which include an approximation for the γ, ρ, π coupling. At the resonance energy our polarization asymmetry is insensitive to this coupling and is in good agreement with the McKinley prediction. At lower energy the agreement is not as good but our data seem to substantiate the need for a negative γ, ρ, π coupling constant.

6 data tables

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Measurement of Polarization in $\pi^- p \to \pi^0n$ and $\pi^-p \to \eta n$

Drobnis, D.D. ; Lales, J. ; Lamb, R.C. ; et al.
Phys.Rev.Lett. 20 (1968) 274-278, 1968.
Inspire Record 942917 DOI 10.17182/hepdata.21731

None

6 data tables

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Measurement of the polarization parameter in n p charge-exchange scattering from 2 to 12 gev/c

Abolins, M.A. ; Lin, M.T. ; Ruchti, R.C. ; et al.
Phys.Rev.Lett. 30 (1973) 1183-1185, 1973.
Inspire Record 84508 DOI 10.17182/hepdata.21408

We have measured the polarization parameter in neuton-proton charge-exchange scattering for incident neutron momenta of 2-12 GeVc and 0.01<~|t|<~1.0 (GeVc)2. Results based on 300 000 events show a negative polarization whose magnitude increases monotonically with |t| approaching 60% for |t|∼0.6 and which has little energy dependence.

1 data table

No description provided.


A Study of Inclusive xi- Production from K- p Interaction at 4.2-GeV/c

The Amsterdam-CERN-Nijmegen-Oxford collaboration Ganguli, S.N. ; Berge, J.P. ; Gavillet, P. ; et al.
Nucl.Phys.B 128 (1977) 408-420, 1977.
Inspire Record 111753 DOI 10.17182/hepdata.36076

A study of inclusive Ξ − production from a high statistics K − p experiment at 4.2 GeV/ c has been made. The total Ξ − production cross section is 157 ± 8 μ b. Approximately 15% of the Ξ − arise from decay of the Ξ ∗0 (1530) resonance. The polarization of the Ξ − is found to be negative and is nearly equal in value to that of the Λ 0 from the inclusive reaction K − + p → Λ 0 + anything. An analysis of the inclusive production of Ξ − has been made in the framework of the triple-Reege formalism.

2 data tables

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The Reactions K- p --> pi-+ Sigma+- at 4.2-GeV/c

The Amsterdam-CERN-Nijmegen-Oxford collaboration Massaro, G.G.G. ; Barlag, S. ; de Groot, A.J. ; et al.
Phys.Lett.B 66 (1977) 385-389, 1977.
Inspire Record 110532 DOI 10.17182/hepdata.27595

We present differential cross sections and the Σ + polarization for the reactions K − p → π ∓ Σ ± using data from a high statistics bubble chamber experiment at 4.2 GeV/ c incident momentum. The statistical level allows a detailed analysis of these reactions over the whole t range. Several significant structures are observed. Comparisons are made with SU(3)-related reactions; for backward production of π − Σ + such a comparison shows good evidence for Δ exchange. The exotic forward peak in K − p → π + Σ − is definitely confirmed.

7 data tables

Axis error includes +- 5/5 contribution.

Axis error includes +- 5/5 contribution.

Axis error includes +- 5/5 contribution.

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d, r, r-prime and p in p p Elastic Scattering from 209-MeV to 515-MeV

Axen, D. ; Felawka, L. ; Jaccard, S. ; et al.
Lett.Nuovo Cim. 20 (1977) 151-156, 1977.
Inspire Record 125649 DOI 10.17182/hepdata.37405

None

5 data tables

POLARIZATION PARAMETER P(N000).

POLARIZATION PARAMETER A(00N0).

WOLFENSTEIN PARAMETER D(N0N0).

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Proton Proton Elastic Scattering from 150-MeV to 515-MeV

Bugg, D.V. ; Edgington, J.A. ; Amsler, Claude ; et al.
J.Phys.G 4 (1978) 1025, 1978.
Inspire Record 123232 DOI 10.17182/hepdata.38563

The parameters D, R, R' and P for pp elastic scattering have been measured in the centre-of-mass angular range 13 degrees to 58 degrees with an accuracy of about +or-0.02 at 209, 324, 379, 425 and 515 MeV. These results are incorporated with earlier data into a phase-shift analysis. Phase-shifts are generally in agreement with the theoretical predictions of the Paris group, although the F-wave spin-orbit combination is rather stronger than predicted. The fitted value for the pi 0pp coupling constant in g02=14.06+or-0.65.

6 data tables

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Polarization Measurement of the $\Sigma^+$ Produced in the Line Reversed Reactions $\pi^+ p \to K^+ \Sigma^+$ and $K^- p \to \pi^- \Sigma^+$ at 7-{GeV}/$c$ and 11.6-{GeV}/$c$

Baker, P.A. ; Chima, J.S. ; Dornan, P.J. ; et al.
Phys.Rev.Lett. 40 (1978) 678, 1978.
Inspire Record 129108 DOI 10.17182/hepdata.20914

The polarization of the Σ+ has been measured for the line-reversed reactions π+p→K+Σ+ and K−p→π−Σ+ at 7 and 11.6 GeV/c using the SLAC Hybrid Facility. Since the Σ+ decay is observed in the bubble chamber, the trigger of the flash lamps on a fast K+(π−) did not bias the polarization measurements. We find that the Σ+ polarizations from the two reactions have opposite signs but similar magnitudes and are in much better agreement with the predictions of weak exchange degeneracy than previous lower-energy comparisons.

1 data table

No description provided.


Confirmation of Exchange Degeneracy Predictions in the Line Reversed Reactions: $\pi^+ p \to K^+ Y^*(1385)$ and $K^- p \to \pi^- Y^*(1385)$ at 11.6-{GeV}/$c$

Ballam, Joseph ; Bouchez, J. ; Carroll, J.T. ; et al.
Phys.Rev.Lett. 41 (1978) 676, 1978.
Inspire Record 130550 DOI 10.17182/hepdata.20815

We have measured in a single experimental setup the differential cross sections and polarizations of the Y*(1385) produced in the two line-reversed reactions π+p→K+Y*(1385) (260 eV/μb) and K−p→π−Y*(1385) (180 eV/μb) at 11.5 GeV/c. We compare these results to Σ+ production in the same experiment. The data have been derived from a triggered bubble-chamber experiment using the SLAC Hybrid Facility. We find that both helicity-flip-dominated (Y*) and helicity-nonflip-dominated (Σ) processes are consistent with weak-exchange-degeneracy predictions.

5 data tables

Axis error includes +- 10/10 contribution.

Axis error includes +- 10/10 contribution.

Axis error includes +- 10/10 contribution.

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VECTOR MESON PRODUCTION IN HYPERCHARGE EXCHANGE REACTIONS AT 7-GeV/c AND 11.5-GeV/c

Ballam, Joseph ; Brau, J. ; Bouchez, J. ; et al.
Nucl.Phys.B 166 (1980) 189-206, 1980.
Inspire Record 143136 DOI 10.17182/hepdata.34582

Results are presented on vector meson production in the hypercharge exchange reactions: π + p → K ∗+ (890) Y + and K − p→ ρ − Y + where Y + is either Σ + or Y ∗+ (1385). These reactions have been studied at 7 GeV/ c and 11.5 GeV/ c using the SLAC Hybrid Facility. Total and differential cross sections, hyperon polarization, and vector meson decay angular distributions are presented. We find that reactions with Σ + production are dominated by natural parity exchange. The Y ∗ (1385) reactions are consistent with substantial natural parity exchange contributions but also show significant unnatural parity exchange. The differential cross sections and polarization measurements for the vector meson production are compared to the pseudoscalar production reactions.

7 data tables

Axis error includes +- 20/20 contribution.

Axis error includes +- 20/20 contribution.

Axis error includes +- 20/20 contribution.

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