The elastic scattering of negative pions on protons at 2.26 GeVc has been studied using the Lawrence Radiation Laboratory 72-in. hydrogen-filled bubble chamber. The elastic scattering cross section is found to be 8.91±0.24 mb. The forward diffraction peak is well fitted by an exponential in the square of the four-momentum transfer, and the slope is found to be 8.8±0.1 GeV−2. The differential cross section is parametrized in terms of three models: optical, strong-absorption, and two-slope. It is found that the two-slope model affords the best description of the data and also does very well in predicting the polarization data of other experiments. The best-fit parameters for all three models are given. In addition, the amplitudes associated with the best fits are given for the strong-absorption and the two-slope models.
No description provided.
None
No description provided.
We present an analysis of ππN final states obtained from π−p interactions at 2.26 GeV/c. Strong ρ production is present in both final states. In addition, significant nucleon isobar production is observed. We observed the following cross sections: σ(π−π0p)=3.77±0.13 mb, σ(π−π+n)=5.67±0.17 mb, σ(ρ−p)=2.19±0.09 mb, σ(Δ+(1236)π−)=0.30±0.10 mb, σ(N0(1650)π0)=0.49±0.07 mb, σ(ρ0n)=2.89±0.11 mb, σ(Δ−(1236)π+)=0.11±0.06 mb, σ(N+(1470)π−)=0.24±0.06 mb, and σ(N+(1650)π−)=0.45±0.05 mb. The spin-density matrix elements are determined for the ρ0 by interpreting the ρ0 asymmetry as an interference between the resonant P wave and a T=0 S wave. A search for the ε0 in the π+π−n final state failed to yield a direct observation of this effect.
No description provided.
None
No description provided.
No description provided.
No description provided.
None
proton-beryllium TOTAL cross section ( 278 mb ) was used for normalization.
Proton-beryllium TOTAL (???) cross section ( 278 mb ) was used for normalization.
The polarized target asymmetry parameter has been measured for single π o photoproduction from hydrogen at 4 GeV and values of four-momentum transfer squared between −0.15 (GeV/ c ) 2 and −1.8 (GeV/ c ) 2 .
Axis error includes +- 0.0/0.0 contribution (?////).
The single-particle inclusive pion spectrum from the reaction p + p → π ± + anything at 28.5 GeV is presented in both tabular and graphical form. The data are from exposures in the BNL 203 cm bubble chamber. The emphasis of this paper is on exhibiting the single-particle spectra in sufficient detail so that the data will be useful to those interested in testing models and developing new concepts.
No description provided.
No description provided.
No description provided.
Differential cross-sections have been measured for π0 photoproduction over the energy range 0.8 GeV to 1.4 GeV and at angles between 50° and 90° c.m.
No description provided.
We present measurements from a spark chamber experiment of the differential cross-sections for p p → π − π + , K − K + at 20 momenta in the range 0.8–2.4 GeV/ c (c.m. energy 2.02 to 2.57 GeV). The c.m. angular range was −0.95 < cos θ ∗ < 0.95 . There are about 2000π − π + events and about 300 K − K + events at each momentum.
ALL ANGLES.
Differential cross sections for the process γ p → p η have been measuredd at c.m. angles of 28°, 35° and 42° at incident energies between 2 GeV and 2.8 GeV. Data from an earlier experiment below 2 GeV have been re-analysed and corrected. The whole set of data is compared with the form ( s − M 2 ) 2 d σ /d t , which fits data at higher energies. There is good agreement above 2 GeV, particularly at the largest angle, but strong departures below.
No description provided.
THESE DATA ARE A REANALYSIS OF THOSE REPORTED IN P. S. L. BOOTH ET AL., NP B25, 510 (1971). THE CORRECTED RESULTS ARE IN GENERAL ABOUT TWICE THE OLD VALUES.
Forum