McCracken, M.E.
nucl-ex
Polarization
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Analyzing powers for the pi- p(pol.) --> pi0 n reaction across the Delta(1232) resonance.

Gaulard, C.V. ; Riedel, C.M. ; Comfort, Joseph R. ; et al.
Phys.Rev.C 60 (1999) 024604, 1999.
Inspire Record 483795 DOI 10.17182/hepdata.51678

High quality analyzing powers for the π−p→→π0n reaction have been obtained with a polarized proton target over a broad angular range at incident kinetic energies of 98.1, 138.8, 165.9, and 214.4 MeV. This experiment nearly doubled the existing πN single-charge-exchange database for energies ranging from 10 to 230 MeV, with 36 new analyzing powers. The Neutral Meson Spectrometer was used to detect the outgoing neutral pions. The data are well described by recent phase-shift analyses. When combined with high-precision and accurate cross section data at the same energies, the data can provide a good test of the degree of isospin breaking in the region of the Δ(1232) resonance. They will also be helpful for constraining the evaluation of the pion-nucleon σ term from the scattering amplitudes.

4 data tables
Table 1

First error is total uncertainty.

Table 2

First error is total uncertainty.

Table 3

First error is total uncertainty.

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Analyzing powers for pi+- p(pol.) elastic scattering between 87-MeV and 263-MeV.

Hofman, G.J. ; Smith, G.R. ; Ambardar, T. ; et al.
Phys.Rev.C 58 (1998) 3484-3493, 1998.
Inspire Record 483008 DOI 10.17182/hepdata.25722

Analyzing powers for πp elastic scattering were measured using the CHAOS spectrometer at energies spanning the Δ(1232) resonance. This work presents π+ data at the pion kinetic energies 117, 130, 139, 155, 169, 180, 193, 218, 241, and 267 MeV and π− data at 87, 117, 193, and 241 MeV, covering an angular range of 50°<~θc.m.<~180° at the higher energies and 90°<~θc.m.<~180° at the lower energies. Unique features of the spectrometer acceptance were employed to reduce systematic errors. Single-energy phase shift analyses indicate the resulting S11 and S31 phases favor the results of the SM95 phase shift analysis over that of the older KH80 analysis.

18 data tables
Table 1

Measurement of the PI+ analysing power at 117 MeV.. The data were collected in the conventional mode and may be independently floated within the systematic error.

Table 2

Measurement of the PI+ analysing power at 139 MeV.. The data were collected in the conventional mode and may be independently floated within the systematic error.

Table 3

Measurement of the PI- analysing power at 87 MeV.. The data were collected in the conventional mode and may be independently floated within the systematic error.

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One-spin pion asymmetry in the d(pol.) + A --> pi+- + X processes near Theta(pi) = 90-degrees.

Averichev, G.S. ; Agakishiev, G. ; Asanova, M.E. ; et al.
Dubna JINR - 1(69)-95 (95/04,rec.Jul.) 27-36, 1995.
Inspire Record 404986 DOI 10.17182/hepdata.70491

None

1 data table
Table 1

No description provided.


Analyzing Powers in $\pi^\pm P$ (Polarized) Elastic Scattering From $T (\pi$) = 98-{MeV} to 263-{MeV}

Sevior, M.E. ; Feltham, A. ; Weber, P. ; et al.
Phys.Rev.C 40 (1989) 2780-2788, 1989.
Inspire Record 288842 DOI 10.17182/hepdata.26219

Angular distributions of the analyzing powers for π+p→ and π−p→ elastic scattering have been measured in a single-scattering experiment employing a polarized proton target. Measurements were obtained for pion energies of 98, 139, 166, 215, and 263 MeV. The addition of these data to the existing πp database significantly reduces the uncertainties in all S and P phase shifts for πp reactions over the delta resonance.

10 data tables
Table 1

Measured values of the analyzing power for PI+ P elastic scattering at incident kinetic energy 98 MeV.

Table 2

Measured values of the analyzing power for PI+ P elastic scattering at incident kinetic energy 139 MeV.

Table 3

Measured values of the analyzing power for PI+ P elastic scattering at incident kinetic energy 166 MeV.

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Left-right Asymmetry in Inverse $\pi^-$ Photoproduction From a Transversely Polarized Proton Target

Kim, G.J. ; Adrian, S.D. ; Arends, J. ; et al.
Phys.Rev.Lett. 56 (1986) 1779-1782, 1986.
Inspire Record 232117 DOI 10.17182/hepdata.20259

Accurate measurements of the left-right asymmetry in π−p→γn at pπ=427−625 MeV/c with a transversely polarized target are reported. Results are compared with the predictions from the Arai and Fujii single-pion photoproduction partial-wave analysis and with data on the inverse process measured with a deuterium target. The agreement is poor, casting doubt on the correctness of the value for the radiative-decay amplitude of the neutral Roper resonance now in use.

5 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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