Electron scattering cross sections for carbon and oxygen between q = 1 fm −1 and 4 fm −1 are given. The data are analysed in terms of a phenomenological charge distribution and new information concerning the tail and the center of the charge distribution are obtained. The presence of dispersion effects appears to be necessary to explain the cross sections in the first diffraction minimum. The effect of a finite potential and short range correlations on the form factor are discussed.
X ERROR D(TARGET) = 99.99 PCT. X ERROR D(THETA) = 0.9300 DEG.
X ERROR D(TARGET) = 99.99 PCT. X ERROR D(THETA) = 0.9300 DEG.
X ERROR D(THETA) = 0.9300 DEG.
Multiple particle production in electron-positron interactions has been observed in an experiment performed at Adone, the Frascati 2×1.5 GeV e+e− storage ring. A total number of 239 events collected at several energies of the incident electron and positron beams between 0.8 and 1.0 GeV were analysed. The distribution of the multiplicity of charged particles produced in the final state is discussed and some upper limits on these multiplicities are reported. The observed lower limit to the total cross-section for multiple particle production in e+e− interactions, averaged over the energy range explored, is 3·10−32 cm2 with a statistical error of ±10% and a systematic uncertainty of ±25%.
LOWER BOUND FROM OBSERVED CHARGED PARTICLES.
Differential cross section for π + photoproduction on hydrogen have been measured over a photon energy range from 220 to 425 MeV and for pion c.m. angles between 15° and 70°. The pions have been analysed in angle and momentum by a magnetic spectrometer.
No description provided.
No description provided.
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.
The differential cross sections for the γ + n → π O + n reaction have been measured at the photon energies of 500–900 MeV. The ratios, R oo = [ d δ d Ω(γ n → π o n ) ] [ d δ d Ω(γ p → π o p ) ] , have been obtained at the c.m. pion angles of 60 O , 90 O , 105 O , 120 O , and 140 O .
Axis error includes +- 0.0/0.0 contribution (8 TO 11////).
Axis error includes +- 0.0/0.0 contribution (8 TO 11////).
Axis error includes +- 0.0/0.0 contribution (8 TO 11////).
In the reaction p p → 3π + 3π − 2227 events, and in the reaction p p → 3π + 3π − π 0 6578 events have been analyzed. The general characteristics of the reactions, such as total cross sections, angular and momentum distributions, the production of ϱ, f, ω and η mesons, and angular correlations are presented.
No description provided.
THETA being the angle between PI+ and P (or PI- and PBAR) in CMS.
THETA being the angle between PI+ and P (or PI- and PBAR) in CMS.
We have measured the e + e − → ø reaction by its K + K − decay mode. Using our previous results on K O K O and the 3π decay mode of the ø mesons, we compute Γ ø → e + e − and then compare the whole Orsay results to theoretical predictions.
FITTED CROSS SECTIONS AT PHI PEAK. ONLY PHI --> K+ K- MEASURED HERE - ANALYSIS USES PREVIOUS EXPERIMENTS FOR OTHER CHANNELS: J.E. AUGUSTIN ET AL., PL 28B, 517 (1969).
EXCITATION OF K+ K- CHANNEL MEASURED AROUND PHI RESONANCE AT 13 ENERGIES.
The cross section for the production of Ξ + particles in K + p interactions at 12.7 GeV/ c is 10 ± 3 μ b; the Ξ − production cross section is 2.5 ± 1.0 μ b; the upper limit on Ω − or Ω + production is 0.4 μb. The Ξ − are produced preferentially in the backward direction in the CM system while the Ξ + are produced mainly forward. The mass and lifetime of the Ξ + agree with the accepted values for the Ξ − hyperon.
Cross sections have been corrected for the detection probability of all observed hyperons involved in these reactions.
The charge excharge reaction K − p → K 0 n has been studied in a event/μb exposure of the CERN 2m hydrogen bubble chamber to a 3.95 GeV/ c K − beam. The differential cross section d σ /d t exhibits a change of slope at −1 ≈ 0.8 GeV 2 .
No description provided.
No description provided.
The differential cross-section for π − d elastic scattering has been measured at 9.0, 13.0, and 15.2 GeV/ c for t -values up to 2.3 GeV 2 . The results are analysed by comparison with the Glauber scattering model.
No description provided.
No description provided.
No description provided.
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