Mass splitting and production of Σ0c and Σ c measured in 500 GeV π--N interactions Article uri icon

abstract

  • From a sample of 2722 ± 78 Λ c decaying to the pK- π final state, we have observed, in the hadroproduction experiment E791 at Fermilab, 143 ± 20 Σ0c and 122 ± 18 Σ c through their decays to Λ cπ±. The mass difference M(Σ0c) - M(Λ c) is measured to be (167. 38± 0.29 ± 0.15) MeV; for M(Σ c) - M(Λ c), we find (167.76 ± 0.29 ± 0.15) MeV. The rate of Λ c production from decays of the Σc triplet is (22 ± 2 ± 3) %25 of the total Λ c production assuming equal rate of production from all three, as measured for Σ0c and Σ c. We do not observe a statistically significant Σc baryon-antibaryon production asymmetry. The χF and p2t spectra of A c from Λ c decays are observed to be similar to those for all A c%27s produced.
  • From a sample of 2722 ± 78 Λ%2bc decaying to the pK- π%2b final state, we have observed, in the hadroproduction experiment E791 at Fermilab, 143 ± 20 Σ0c and 122 ± 18 Σ%2b%2bc through their decays to Λ%2bcπ±. The mass difference M(Σ0c) - M(Λ%2bc) is measured to be (167. 38± 0.29 ± 0.15) MeV; for M(Σ%2b%2bc) - M(Λ%2bc), we find (167.76 ± 0.29 ± 0.15) MeV. The rate of Λ%2bc production from decays of the Σc triplet is (22 ± 2 ± 3) %25 of the total Λ%2bc production assuming equal rate of production from all three, as measured for Σ0c and Σ%2b%2bc. We do not observe a statistically significant Σc baryon-antibaryon production asymmetry. The χF and p2t spectra of A%2bc from Λ%2bc decays are observed to be similar to those for all A%2bc%27s produced.
  • From a sample of 2722 ± 78 Λ%2bc decaying to the pK- π%2b final state, we have observed, in the hadroproduction experiment E791 at Fermilab, 143 ± 20 Σ0c and 122 ± 18 Σ%2b%2bc through their decays to Λ%2bcπ±. The mass difference M(Σ0c) - M(Λ%2bc) is measured to be (167. 38± 0.29 ± 0.15) MeV; for M(Σ%2b%2bc) - M(Λ%2bc), we find (167.76 ± 0.29 ± 0.15) MeV. The rate of Λ%2bc production from decays of the Σc triplet is (22 ± 2 ± 3) %25 of the total Λ%2bc production assuming equal rate of production from all three, as measured for Σ0c and Σ%2b%2bc. We do not observe a statistically significant Σc baryon-antibaryon production asymmetry. The χF and p2t spectra of A%2bc from Λ%2bc decays are observed to be similar to those for all A%2bc's produced.

authors

publication date

  • 1996-01-01