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.
Measured values of the analyzing power for PI+ P elastic scattering at incident kinetic energy 98 MeV.
Measured values of the analyzing power for PI+ P elastic scattering at incident kinetic energy 139 MeV.
Measured values of the analyzing power for PI+ P elastic scattering at incident kinetic energy 166 MeV.
Results are presented of an analysis of the reaction pp→p f (K S 0 K ± π ∓ )p s at 300 GeV/ c . Clear f 1 (1285) and f 1 (1420) signals are seen. A spin-parity analysis shows that both are consistent with being 1 ++ states. The f 1 (1420) is found to decay only to K ∗ K and no 0 −+ or 1 +− waves are required to describe the data. The production of the f 1 (1285) as a function of energy is not the same as that for the f 1 (1420) whose cross section is found to be constant with energy.
No description provided.
The total cross section for e + e − annihilation into hadrons has been measured for CM energies ranging from 50 to 57 GeV. We fit the predictions of the standard model to these measurements and those at lower energies. The mass of the Z 0 boson, M Z , and the QCD scale parameter, Λ MS , are derived from the fit. The results are M Z =88.6 −1.8 +2.0 GeV/ c 2 , and Λ MS =0.15 −0.11 +0.16 GeV .
No description provided.
Inclusive production cross sections of charged pions on carbon, copper and bismuth by neutrons in the energy range of 300–580 MeV have been measured from 54° to 164°. The invariant cross sections can be expressed by Full-size image (<1 K) for the high-energy part of the pion spectra. The slope parameter exhibits a systematic variation with neutron energy and emission angle for the three targets. The dependence of the pion production on the target mass number varies strongly with pion energy and emission angle. The production cross sections are compared with the model of quasi-two-body scaling, the moving-source model and with intranuclear cascade calculations.
No description provided.
We have measured the asymmetry of elastic pp scattering at small scattering angles (30–100 mrad) in the Coulomb-nuclear interference region, using the polarized proton beam of Saturne II, a segmented scintillator active target, and two telescopes of multiwire proportional chambers. Results are given at four energies — 940, 1000, 1320 and 2440 MeV-and are compared with phase-shift calculations.
No description provided.
No description provided.
No description provided.
Correlations between target fragments were measured in α- and 14 N-induced reactions at 70, 250 and 800 MeV/u incident energies. The reaction mechanism is characterized by the linear momentum transfer and the excitation energy which were deduced from the kinematics and the mass distribution of the fission fragments. By selecting targets lighter than Th (Au and Ho) the yield from peripheral collisions is reduced by the increase in the fission barrier thus allowing events with the highest linear momentum transfer and excitation energy to be favoured. The results show that up to an incident energy of 800 MeV/u hot nuclei are formed which decay via normal binary fission. The linear momentum transfer is essentially constant over the covered energy range, but the excitation energy increases until the total incident energy is greater than 3 GeV. At this energy, independent of the projectile mass the fission probability of the heavy nuclei drops below 50%, while the emission of intermediate-mass fragments increases. The relative velocities between two intermediate-mass fragments exceed strongly the values of binary fission. Monte Carlo calculations show that the relative velocities between these fragments exclude a sequential emission from the recoil nucleus and support a simultaneous breakup mechanism.
SIG IS FISSION CROSS-SECTION CALCULATED WITH THE SOFT-SPHERE MODEL OF REF. PHYS.REV.C11 (1975) 1203.
SIG IS FISSION CROSS-SECTION CALCULATED WITH THE SOFT-SPHERE MODEL OF REF. PHYS.REV.C11 (1975) 1203.
SIG IS FISSION CROSS-SECTION CALCULATED WITH THE SOFT-SPHERE MODEL OF REF. PHYS.REV.C11 (1975) 1203.
None
No description provided.
No description provided.
No description provided.
We have measured the inclusive production of γ, π0 and η ine+e− annihilation at the center of mass energy of 35 GeV. The differential cross sections, extended to the kinematical limit and measured with high accuracy, are found to be in good agreement with previously reported results. Using the measured spectra we determine the average multiplicity for each of these particle species.
No description provided.
Statistical errors only.
Statistical errors only.
None
206 EVENTS.
206 EVENTS.
4000 EVENTS.
The production of neutral pions by the interaction of 200A·GeV p and16O projectiles with a Au target has been studied in the pseudorapidity range 1.5≦η≦2.1. Transverse momentum spectra have been measured between 0.4 GeV/c and 3.6 GeV/c and their dependence on the centrality of the collision has been investigated. The peripheral-collision spectra display a marked change of slope with a hard component starting at about 1.8 GeV/c, in contrast to central-collision data. The data are discussed in comparison to p+p and α+α data from the ISR.
Data obtained with minimum bias trigger conditions.
Data obtained with minimum bias trigger conditions.
Data for central collisions.
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