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The polarization of the recoil proton in π+p and π−p elastic scattering using a liquid-hydrogen target has been measured for backward angles at 547 and 625 MeV/c. The scattered pion and recoil proton were detected in coincidence using the large-acceptance spectrometer to detect and analyze the momentum of the pions and the JANUS polarimeter to identify and measure the polarization of the protons. Results from this experiment agree with other measurements of the recoil polarization, with analyzing-power data previously taken by this group, and with predictions of partial-wave analyses.

2 data tables match query

Table 1

No description provided.

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Analyzing power for pi- p charge exchange in the backward hemisphere from 301-MeV/c to 625-MeV/c and a test of pi N partial wave analyses

Kim, G.J. ; Arends, J. ; Engelage, J. ; et al.

Phys.Rev.D 41 (1990) 733-743, 1990.

Inspire Record 301242 DOI 10.17182/hepdata.22935

The analyzing power of π−p→π0n has been measured for pπ=301−625 MeV/c with a transversely polarized target, mainly in the backward hemisphere. The final-state neutron and a γ from the π0 were detected in coincidence with two counter arrays. Our results are compared with predictions of recent πN partial-wave analyses by the groups of Karlsruhe-Helsinki, Carnegie-Mellon University-Lawrence Berkeley Laboratory (CMU-LBL), and Virginia Polytechnic Institute (VPI). At the lower incident energies little difference is seen among the three analyses, and there is excellent agreement with our data. At 547 MeV/c and above, our data strongly favor the VPI phases, and disagree with Karlsruhe-Helsinki and CMU-LBL analyses, which are the source of the πN resonance parameters given in the Particle Data Group table.

3 data tables match query

Table 3

Axis error includes +- 5/5 contribution (Uncertainty in background normalisation).

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Axis error includes +- 5/5 contribution (Uncertainty in background normalisation).

Table 5

Axis error includes +- 5/5 contribution (Uncertainty in background normalisation).

$\pi^- P$ Charge Exchange Analyzing Power From 547-{MeV}/c to 687-{MeV}/c

Wightman, J.A. ; Eichon, A.D. ; Kim, G.J. ; et al.

Phys.Rev.D 38 (1988) 3365-3374, 1988.

Inspire Record 270260 DOI 10.17182/hepdata.23237

The π−p charge-exchange analyzing power has been measured from 547 to 687 MeV/c in the center-of-mass angular range -0.9≤cosθ̃π≤0.9 using a transversely polarized target. The recoil neutron was detected in coincidence with a photon from π0 decay. The results are compared with the three recent partial-wave analyses (PWA’s); the VPI analysis is most consistent with our measured distributions except at 687 MeV/c where no PWA agrees with our data. The charge-exchange transversity cross sections are evaluated using the differential cross sections of Borcherding et al. These transversity cross sections are used in conjunction with earlier π±p data by our group to test the triangle inequalities which are a model-independent test of isospin invariance. Our data satisfy these inequalities everywhere; in contrast, Abaev et al. have reported a violation of more than 5 standard deviations at 685 MeV/c.

1 data table match query

Table 1

No description provided.

Analyzing Power for $\pi^- P$ Charge Exchange and a Test of Isospin Invariance Up to $\eta$ Threshold

Wightman, J.A. ; Eichon, A.D. ; Kim, G.J. ; et al.

Phys.Rev.D 36 (1987) 3529-3532, 1987.

Inspire Record 255689 DOI 10.17182/hepdata.23322

The analyzing power for π−p→π0n has been measured at five incident momenta from 547 to 687 MeV/c using a transversely polarized target. Data were obtained with scintillation counters at 10 angles simultaneously covering the range −0.9≤cosθc.m.π≤0.9. Our results and those of Kim et al. are used for a model-independent test of isospin invariance which is based on the triangle inequalities applied to the transversity-up as well as the transversity-down cross sections. No evidence is found of isospin violation.

1 data table match query

Table 1

No description provided.

A MEASUREMENT OF THE ANALYZING POWER FOR PION - PROTON ELASTIC SCATTERING BETWEEN 471-MeV/c AND 687-MeV/c

Mokhtari-Amirmajdi, Alireza ;

LA-10451-T, 1985.

Inspire Record 217838 DOI 10.17182/hepdata.23514

None

4 data tables match query

Table 1

No description provided.

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Proton Polarization in gamma p --> pi0 p Reaction at an Angle of Theta (pi) = 100-Degrees in CMS in the Second pi n Resonance Region

Derebchinsky, A.I. ; Zybalov, A.A ; Konovalov, O.G. ; et al.

Yad.Fiz. 28 (1978) 265-266, 1978.

Inspire Record 135482 DOI 10.17182/hepdata.19013

None

1 data table match query

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Polarisation of recoil neutrons from single-pion photoproduction off protons in the resonance region

Measurement of the polarization of the backscattered neutron from the reaction gamma p -> pi n in the region of the second resonance

ASYMMETRY MEASUREMENTS IN PION PHOTOPRODUCTION BY POLARIZED PHOTONS IN THE ENERGY RANGE FROM 250-MeV TO 600-MeV

Measurement of the polarization parameter in $\pi^{pm}p$ scattering from 356 to 519 MeV/c

Recoil Proton Polarization in $\pi P$ Elastic Scattering at 547-{MeV}/c and 625-{MeV}/c

Analyzing power for pi- p charge exchange in the backward hemisphere from 301-MeV/c to 625-MeV/c and a test of pi N partial wave analyses

$\pi^- P$ Charge Exchange Analyzing Power From 547-{MeV}/c to 687-{MeV}/c

Analyzing Power for $\pi^- P$ Charge Exchange and a Test of Isospin Invariance Up to $\eta$ Threshold

A MEASUREMENT OF THE ANALYZING POWER FOR PION - PROTON ELASTIC SCATTERING BETWEEN 471-MeV/c AND 687-MeV/c

Proton Polarization in gamma p --> pi0 p Reaction at an Angle of Theta (pi) = 100-Degrees in CMS in the Second pi n Resonance Region