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Inclusive hadron photoproduction from longitudinally polarized protons and deuterons.

The E155 collaboration Anthony, P.L. ; Arnold, R.G. ; Averett, T. ; et al.
Phys.Lett.B 458 (1999) 536-544, 1999.
Inspire Record 495554 DOI 10.17182/hepdata.28074

We report measurements of the asymmetry A_parallel for inclusive hadron production on longitudinally polarized proton and deuteron targets by circularly polarized photons. The photons were produced via internal and external bremsstrahlung from an electron beam of 48.35 GeV. Asymmetries for both positive and negative signed hadrons, and a subset of identified pions, were measured in the momentum range 10<P<30 GeV at 2.75 and 5.5 degrees. Small non-zero asymmetries are observed for the proton, while the deuteron results are consistent with zero. Recent calculations do not describe the data well.

4 data tables match query
Table 1

The asymmetry for polarized photoproduction of inclusive hadrons from a polarized proton target. The errors are statistical only.

Table 2

The asymmetry for polarized photoproduction of inclusive identified pions from a polarized proton target. The errors are statistical only.

Table 3

The asymmetry for polarized photoproduction of inclusive hadrons from a polarized deuteron target. The errors are statistical only.

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Polarization at Small Angles in Anti-proton - Carbon Elastic Scattering at {LEAR} Energies

The SING collaboration Martin, A. ; Birsa, R. ; Bos, K. ; et al.
Nucl.Phys.A 487 (1988) 563-590, 1988.
Inspire Record 261245 DOI 10.17182/hepdata.37001

A double-scattering experiment of antiprotons on carbon has been carried out at the Low-Energy Antiproton Ring (LEAR) at CERN, to measure the polarization parameter A p C in antiproton-carbon elastic scattering at small angles. The polarization parameter has been inferred from the azimuthal distribution of the antiprotons after the second scattering. Data have also been collected with a liquid-hydrogen target as the second scatterer, thus allowing the sign of A p C to be determined. The experiment has been performed at two momenta of the extracted antiproton beam, 800 and 1100 MeV/c. A small positive value of the polarization has been observed, compatible with energy independence and a linear increase with the momentum transfer q . Parametrizing A p C as a c q , we get a c = +0.72 0.10 +0.09 ( GeV / c ) −1 . This result is compared with potential model predictions for N̄N amplitudes through a Glauber theory calculation.

6 data tables match query
Table 1

THETA1(RF=LAB)=8 DEG, THETA POINTED IN TABLE IS THE SECOND SCATTERING ANGLE.

Table 2

THETA1(RF=LAB)=5 DEG, THETA POINTED IN TABLE IS THE SECOND SCATTERING ANGLE.

Table 3

THETA1(RF=LAB)=8 DEG, THETA POINTED IN TABLE IS THE SECOND SCATTERING ANGLE.

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CROSS-SECTION ASYMMETRY OF THE gamma n ---> pi- p REACTION BY POLARIZED PHOTONS IN THE THIRD AND FOURTH RESONANCE REGIONS

Adamian, F.V. ; Akopian, G.G. ; Galumian, P.I. ; et al.
EFI-722-37-84-YEREVAN, 1984.
Inspire Record 206944 DOI 10.17182/hepdata.18433

None

5 data tables match query
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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Measurement of the neutral weak form factors of the proton.

The HAPPEX collaboration Aniol, K.A. ; Armstrong, D.S. ; Baylac, M. ; et al.
Phys.Rev.Lett. 82 (1999) 1096-1100, 1999.
Inspire Record 478059 DOI 10.17182/hepdata.31319

We have measured the parity-violating electroweak asymmetry in the elastic scattering of polarized electrons from the proton. The kinematic point (theta_lab = 12.3 degrees and Q^2=0.48 (GeV/c)^2) is chosen to provide sensitivity, at a level that is of theoretical interest, to the strange electric form factor G_E^s. The result, A=-14.5 +- 2.2 ppm, is consistent with the electroweak Standard Model and no additional contributions from strange quarks. In particular, the measurement implies G_E^s + 0.39G_M^s = 0.023 +- 0.034 (stat) +- 0.022 (syst) +- 0.026 (delta G_E^n), where the last uncertainty arises from the estimated uncertainty in the neutron electric form factor.

1 data table match query
Table 1

Longitudinally polarized beam. C=L and C=R means left- and right polarization. The second systematic uncertainty arises from the estimated uncertainty inthe neutron electromagnetic from factor.