Proton-proton elastic scattering has been measured over the angular range 7 to 16 mrad at centre-of-mass energies of 31, 45 and 53 GeV using the CERN Intersecting Storage Rings. The results indicate that the diffraction peak has continued to shrink with increasing energy, but not as fast as suggested by the results at lower energies.
No description provided.
3 H̃e nuclei were observed in the negative beam, produced by 70 GeV protons on an Al target. Five 3 H̃e have been identified among 2.4 · 10 11 particles that passed through the apparatus. Scintillation and Čerenkov counters were used to measure the electrical charge and velocity of particles. The mass of 3 H̃e is found to be M 3 H ̃ e = (1.00 ± 0.03)3m p , the charge is z = (0.99 ± 0.03)2 e . The ratio of differential production cross sections of 3 H ̃ e (P = 20 GeV /c) and π − (P = 10 GeV/c ) equals 2 · 10 −11 . This corresponds to antihelium −3 production cross section d 2 σ 3 H ̃ e / d Ω d P = 2.0 · 10 −35 cm 2 / sr · GeV /c per Al nuclei and 2.2 · 10 −36 cm 2 sr · GeV/ c per nucleon.
No description provided.
No description provided.
A systematic search for exotic states produced in K − d interactions at 3 GeV/ c is reported. From the analysis of the mass spectra of strange mesons, non-strange mesons, hyperons with S = −1 and S = −2, upper limits for the production cross sections of exotic resonances may be placed at one or two orders of magnitude smaller than for the production of normal resonances of same strangeness and baryon number.
No description provided.
The results of the experiment searching for quarks with charge − 1 3 and 2 3 produced by 70 GeV protons on an aluminium target at zero angle are reported. For the selection of quarks the system of spectrometric scintillation counters, time-of-flight spectrometer, gas Cerenkov threshold counter and magnetic spectrometer with spark chambers were used. In the range of masses available at the IHEP accelerator, quarks were not found. The upper limit estimation of the differential cross-section for quark production with mass ⩽ 5 GeV /c 2− and charge −1 3 is 7×10 −38 cm 2 / ster GeV /c (with 90% confidence level). The total cross-section for quark production with charge −1 3 and mass 4.5–5 GeV /c 2 does not exceed 3×10 −39 cm 2 .
No description provided.
No description provided.
Results are presented from an experiment in which high-energy deuterons, produced by proton-proton interactions at 21.1 GeV/ c incident momentum, were detected over a range of angles from 12.5 mrad to 60 mrad in the laboratory system. From the momentum spectra of the deuterons, the final states D + π + and D + ϱ + have been identified. The angular distribution for these reactions are presented and compared with previous data at lower energies.
The statistical errors are presented.
The statistical errors are presented.
The statistical errors are presented. The data are from previous publications.
Experimental results are presented on the excitation of the nucleon isobars N ∗ (1518) and N ∗ (1688) in proton-proton collisions at an incident momentum of 19.2 GeV/ c and in the range of four-momentum squared 0.6 ⩽7 z . sfnc ; t | ⩽ 5.8 GeV 2 .
Axis error includes +- 0.0/0.0 contribution (?////Due to the method used in estimating the area under the peak).
Axis error includes +- 0.0/0.0 contribution (?////Due to the method used in estimating the area under the peak).
Axis error includes +- 0.0/0.0 contribution (?////Due to the method used in estimating the area under the peak).
Results are presented on measurements of elastic proton-proton scattering at 19.2 and 21.1 GeV/ c in the angular region where previously structure had been observed at lower energies.
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