The reaction γ + p → Φ + p has been measured using a spark chamber spectrometer and a tagged photon beam in the energy range from 4.6 to 6.7 GeV. Approximately 3500 photoproduced elastic Φ-events have been collected in the t -range between t min and t = −0.4 (GeV/ c ) 2 . Cross sections and t -distributions are presented.
A comprehensive survey of event-by-event fluctuations of charged hadron multiplicity in relativistic heavy ions is presented. The survey covers Au+Au collisions at sqrt(s_NN) = 62.4 and 200 GeV, and Cu+Cu collisions sqrt(s_NN) = 22.5, 62.4, and 200 GeV. Fluctuations are measured as a function of collision centrality, transverse momentum range, and charge sign. After correcting for non-dynamical fluctuations due to fluctuations in the collision geometry within a centrality bin, the remaining dynamical fluctuations expressed as the variance normalized by the mean tend to decrease with increasing centrality. The dynamical fluctuations are consistent with or below the expectation from a superposition of participant nucleon-nucleon collisions based upon p+p data, indicating that this dataset does not exhibit evidence of critical behavior in terms of the compressibility of the system. An analysis of Negative Binomial Distribution fits to the multiplicity distributions demonstrates that the heavy ion data exhibit weak clustering properties.
The mean from the NBD fit as a function of $N_{part}$ for 200 GeV Au+Au collisions over the range 0.2 < $p_T$ < 2.0 GeV/$c$.
The mean from the NBD fit as a function of $N_{part}$ for 62.4 GeV Au+Au collisions over the range 0.2 < $p_T$ < 2.0 GeV/$c$.
Results are presented of measurements of the polarisation parameter for the reaction π−p→π°n : π°→γγ at 22 incident momenta in the resonance region. These results are generally in agreement with those of previous measurements and in qualitative agreement with predictions of phase shift analyses.
No description provided.
The differential cross sections of the combined elastic and break-up K − d reaction have been measured at 1.21, 1.42 and 2.61 GeV/ c incident K − momentum. The measurements have been performed at the CERN PS using multiwire proportional chambers. The values of the invariant momentum transfer t explored (0.0005<| t |<0.1 GeV 2 ) include the Coulomb-nuclear interference region. The differential cross sections have been analysed in the framework of the Glauber impact-parameter formalism. The observed interference effects have been used to derive the ratio of the real to imaginary part of the forward K − n nuclear amplitude.
SUM OF COHERENT AND BREAK-UP SCATTERING.
SUM OF COHERENT AND BREAK-UP SCATTERING.
SUM OF COHERENT AND BREAK-UP SCATTERING.
The production of the Lambda and Sigma0 hyperons has been measured via the pp->pK+Lambda / Sigma0 reaction at the internal COSY-11 facility in the excess energy range between 14 and 60 MeV. The transition of the Lambda/Sigma0 cross section ratio from about 28 at Q<=13 MeV to the high energy level of about 2.5 is covered by the data showing a strong decrease of the ratio between 10 and 20 MeV excess energy. Effects from the final state interactions in the p-Sigma0 channel seem to be much smaller compared to the p-Lambda one. Estimates of the effective range parameters are given for the N-Lambda and the N-Sigma systems.
Cross section for LAMBDA production.. Statistical errors only.
Cross section for SIGMA0 production.. Statistical errors only.
Energy dependence of the LAMBDA/SIGMA0 ratio.
A polarized proton beam extracted from SATURNE II, the Saclay polarized target with$^6$Li compounds, and
The polarization transfer parameter KNN measured with polarized protons on the polarized LiH and LiD targets. The relative uncertainty due to the P-C analysing power is +- 6 PCT.
A polarized proton beam extracted from SATURNE II and the Saclay polarized proton target were used to measure the rescattering observables$K_{onno}$and
No description provided.
The differential cross section of the reaction ( γ p → p φ ) has been measured in the t range 0 ⩽ t ⩽ 0.4 GeV 2 and for photon energies from 3.0 to 6.7 GeV. In particular for the small t region the measurement accuracy was better than 10%. We obtained for the slope parameter B in an exponential parametrization of the differential cross section d σ /d t = A e − Bt values of B ⋍ 6 ± 0.5 GeV −2 which are significantly larger than the slopes obtained by most other experiments at higher t values. This indicates a t dependence of B particularly in the small t region.
No description provided.
No description provided.
No description provided.
Results are presented of polarization parameter measurements for the reaction π − p→ π 0 n at 22 momenta between 617 and 2267 MeV/ c . These results are generally in agreement with those of previous measurements and in qualitative agreement with predictions of phase-shift analyses. Together with the recently published differential cross-section measurements, they provide a comprehensive set of data for this reaction in the resonance region.
No description provided.
Results are presented of differential cross-section measurements for the reaction π − p→ π 0 n; π 0 → γγ at 22 incident pion momenta between 618 and 2724 MeV/ c . The results are in good agreement with those of other experiments. They represent the first comprehensive set of high statistics measurements of the π − p charge-exchange differential cross section at closely spaced momenta in the resonance region.
No description provided.
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