None
No description provided.
The rates for forward electroproduction of single charged pions from deutrium have been measured in the resonance region, at a virtual photon mass squared ≈−0.5( GeV/ c 2 ) 2 . Results are presented in the form of a π − to π + cross-section ratio.
No description provided.
We have investigated inclusive Λ , Λ and Σ ± (1385) productions in 405 GeV/ c pp interactions. The observed cross sections are σ ( Λ )=4.05±0.39 mb, σ( Λ =0.63±0.17 mb, σ ( Σ + (1385))=0.74±0.17 mb and σ ( Λ − (1385))=0.56±0.17 mb. Λ production is dominant in a central region of ∣ x ∣≤0.4. The Λ/ Λ production ratio at ∣ x ∣≈0 is found to be 1.2±0.5. The excess, about 0.2 mb, of σ ( Λ + (1385)) over σ ( Λ − (1385)) is most likely attributed to proton fragmentations (∣ x ∣≥0.4), and gives an evidence for scaling.
No description provided.
No description provided.
No description provided.
The vector meson production, hypercharge exchange reactions K − p → ( φ , ω , ϱ ) Λ and ( φ , ϱ ) Σ 0 are studied at 4.2 GeV/ c incident momentum. The data come from a high statistics bubble chamber experiment with a sensitivity of ∼ 120 events/μb. Total and differential cross sections are presented. The vector meson density matrix elements and hyperon polarization are investigated as functions of momentum transfer. Amplitude analyses are performed for all five reactions. The results are compared with duality and quark model predictions, as well as used to test current ideas in two-body phenomenology.
ERRORS INCLUDE THE 5 PCT MODEL ERROR BUT NOT THEORETICAL RESONANCE PARAMETRIZATION ERRORS.
No description provided.
No description provided.
We present results on flux-normalized neutrino and antineutrino cross sections near y=0 from data obtained in the Fermilab narrow-band beam. We conclude that values of σ0=dσdy|y=0 are consistent with rising linearly with energy over the range 45<~Eν<~20.5 GeV. The separate averages of ν and ν¯, each measured to 4%, are equal to well within the errors. The best fit for the combined data gives σ0E=(0.719±0.035)×10−38 cm2/GeV at an average Eν of 100 GeV.
FE nucleus. The SIG/Enu is fitted to CONST(N=SIG)+CONST(N=T)*E.
FE nucleus. Averaged over the energies and beams.
The reactions K − d→ Σ − p, K − d→ Σ − (1385)p, K − d→ Λ (1405)n and K − d→ Λ (1520)n have been studied at K − momenta between 686 and 844 MeV/ c in an experiment with the 81 cm Saclay bubble chamber at CERN. About 630 000 pictures have been analyzed. Partial and differential cross sections are presented. A one-nucleon-exchange model is used to extract the kaon-nucleon-hyperon coupling constants from these results. For g( K N Σ(1197)), g( K N Σ(1385)) and g( K N Λ(1405)) we find values which are compatible with the SU(3) predictions. The coupling constant g( K N Λ(1520)) obtained by our method agrees with that determined from the partial decay width for Λ(1520)→ K N .
CROSS SECTIONS FROM FITTING WITH BREIT-WIGNER DISTRIBUTIONS AND SMOOTH BACKGROUND.
CROSS SECTION WITH A T-CUT.
CROSS SECTION WITH A T-CUT.
Charged hadron production via e + e − → h ± X where h ± = π ± , K ± , p ̄ has been measured for s values between 13 and 25 GeV 2 . Inclusive cross sections and the evidence for scaling are presented.
No description provided.
The total cross section for K ± production in e + e − collisions was measured for cms energies between 3.6 and 5 GeV and was found to increase by a factor of 2–3 from 3.6 to 4.1 GeV.
No description provided.
Differential cross sections and polarizations have been measured for the backward peaks in the reactions π − p →Λ K 0 and π − p →Λ K ∗ (890) at 8 GeV/c. The experiment was performed with a liquid hydrogen target at the ω spectrometer. The cross sections for u′>−2 ( GeV /c) 2 are 0.27 ± 0.03 μ b for π − p →Λ+ K 0 and 0.55±0.07 μ b for π − p →Λ K ∗0 . Large positive Λ polarization was observed in both reactions for u ′>−0.5 (GeV/ c ) 2 . The dominant production mechanism was found to be unnatural baryon exchange.
Axis error includes +- 0.0/0.0 contribution (?////).
Axis error includes +- 0.0/0.0 contribution (?////).
No description provided.
None
No description provided.
Forum