The asymmetry ratio for the process γ + p → n + π + by linearly polarized γ rays are reported for E γ = 200 − 400 MeV and for θ (production angle of π in the c.m. system) = 90°. The experimental results are compared with some recent theoretical predictions.
No description provided.
No description provided.
No description provided.
None
Axis error includes +- 3/3 contribution.
Axis error includes +- 3/3 contribution.
Axis error includes +- 3/3 contribution.
The polarization of the recoil neutrons from the reaction γ p→ π + n was measured at a c.m. angle of 105° for incident photon energies between 675 and 1125 MeV. A scattered π + meson and a recoil neutron were detected in coincidence with a magnetic spectrometer and a neutron polarimeter system using liquid hydrogen. Results are compared with recent phenomenological analyses and the other existing data measured by the double polarization measurement technique.
ERRORS ARE STATISTICAL ONLY.
Measurements have been made on the ratio of pion-production cross sections at right angles to and along the photon electric-field vector. The positive and negative pions were first momentum-analyzed and counted by means of a counter telescope. Data have been taken at 45, 90, and 135° in the c.m. system, and at proton energies of 225, 330, and 450 MeV. A comparison of the data is made with the dispersion-relation calculation of McKinley.
No description provided.
No description provided.
Single π + production on protons by linearly polarized photons of 2.5 to 5 GeV was measured at squared four momentum transfers t between −0.01 and −0.6 (GeV/ c ) 2 . The results show that the differential cross section d σ ⊥ d t with the electric vector of the photon perpendicular to the reaction plane is much larger than d σ ‖ d t with the electric vector parallel to the reaction plane. The predictions of Regge models and of the vector meson dominance model are briefly discussed.
Axis error includes +- 0.0/0.0 contribution (?////).
Axis error includes +- 0.0/0.0 contribution (?////).
Axis error includes +- 0.0/0.0 contribution (?////).
The target asymmetry T = ( σ ↑ − σ ↓)/( σ ↑ + σ ↓) for the reaction γ p → π + n has been measured at the Bonn 2.5 GeV electron synchrotron for a pion c.m. angle of 40° and γ energies between 0.5 and 2.2 GeV. Butanol was used as the target material. About 35% of the protons could be polarized using the dynamic-polarization method in a continuous-flow cryostat operating at 1°K and 25 kG. The π + mesons were detected in a magnetic-spectrometer system. Considerable structure in the asymmetry was observed.
Axis error includes +- 11/11 contribution.
None
Axis error includes +- 10./10. contribution (DUE TO BEAM POLARIZATION UNCERTAINTY).
D(SIG)/D(OMEGA)=(D(SIG(O))/D(OMEGA)+D(SIG(C))/D(OMEGA))/2, WHERE (O) AND (C) DENOTES GAMMA POLARIZATION ORTHOGONAL AND COPLANAR TO THE REACTION PLANE.
Axis error includes +- 10./10. contribution (DUE TO BEAM POLARIZATION UNCERTAINTY).
None
Axis error includes +- 10/10 contribution (DUE TO BEAM POLARIZATION UNCERTAINTY).
Axis error includes +- 10/10 contribution (DUE TO BEAM POLARIZATION UNCERTAINTY).
None
No description provided.
No description provided.