x / 03 02 03 9 v 1 2 5 Fe b 20 03 Production Asymmetry of D s from 600 GeV / c Σ − and π − beam ( SELEX Collaboration )

ar X iv : h ep - p h / 03 02 10 9 v 1 1 3 Fe b 20 03 LBNL - 52160 Ξ − and Ω Distributions in Hadron - Nucleus Interactions 1

Strange baryons have long been known to exhibit a leading particle effect. A recent comparison of Ξ − production in π − , n, and Σ − interactions with nuclei show this effect clearly. These data are supplemented by earlier measurements of Ξ − and Ω production by a Ξ − beam. We calculate the Ξ − and Ω x F distributions and nuclear dependence in hA interactions using the intrinsic model.

ar X iv : h ep - e x / 98 12 01 9 v 1 1 6 D ec 1 99 8 Hyperon Physics Results from SELEX 1 The Selex Collaboration

In parallel to charm hadroproduction the experiment Selex (E781) at Fermilab is pursuing a rich hyperon physics program. Selex employs a 600 GeV/c beam consisting of 50 % Σ− and π− each. The three-stage magnetic spectrometer covering 0.1 ≤ xF ≤ 1.0 features a high-precision silicon vertex system, broad-coverage particle identification using TRD and RICH, and a three-stage lead glass photon calo...

ar X iv : h ep - p h / 03 02 12 9 v 1 1 7 Fe b 20 03 Scalar σ meson effects in radiative ρ 0 - meson decays

v 1 2 5 O ct 1 99 9 . Total Cross Section Measurements with π − , Σ − and Protons on Nuclei and Nucleons around 600 GeV / c

Total cross sections for Σ− and π− on beryllium, carbon, polyethylene and copper as well as total cross sections for protons on beryllium and carbon have been measured in a broad momentum range around 600GeV/c. These measurements were performed with a transmission technique adapted to the SELEX hyperon-beam experiment at Fermilab. We report on results obtained for hadron-nucleus cross sections ...

ar X iv : h ep - e x / 01 06 05 3 v 1 1 3 Ju n 20 01 Measurement of the Σ − Charge Radius by Σ − – Electron Elastic Scattering The SELEX

The Σ− mean squared charge radius has been measured in the space-like Q range 0.035–0.105 GeV/c by elastic scattering of a Σ− beam off atomic electrons. The measurement was performed with the SELEX (E781) spectrometer using the Fermilab hyperon beam at a mean energy of 610 GeV/c. We obtain 〈r2 ch〉Σ− = (0.61 ± 0.12 (stat.) ± 0.09 (syst.)) fm. The proton and π− charge radii were measured as well ...