Results are presented of a measurement of the production of ${D}^{\mathrm{*}+}$ (${D}^{\mathrm{*}\mathrm{\ensuremath{-}}}$) in 250-GeV/c ${\ensuremath{\pi}}^{\mathrm{\ensuremath{-}}}$N interactions. We observe 2.1\ifmmode\pm\else\textpm\fi{}7.8 events corresponding to a charge-${D}^{\mathrm{*}}$ cross section \ensuremath{\sigma}(${D}^{\mathrm{*}}$) of 0.4\ifmmode\pm\else\textpm\fi{}1.5 \ensuremath{\mu}b/nucleon. When averaged with our previous measurement made at 200 GeV/c, the result is \ensuremath{\sigma}(${D}^{\mathrm{*}}$)=2.3\ifmmode\pm\else\textpm\fi{}1.0 \ensuremath{\mu}b/nucleon with (d\ensuremath{\sigma}/dx)${\ensuremath{\Vert}}_{x=0}$=4.6\ifmmode\pm\else\textpm\fi{}2.0 \ensuremath{\mu}b.

We report ${\ensuremath{\Sigma}}^{\ensuremath{-}}n$ mass spectra for the reaction $^{2}\mathrm{H}({K}^{\ensuremath{-}},{\ensuremath{\pi}}^{+}){\ensuremath{\Sigma}}^{\ensuremath{-}}n$ at ${\ensuremath{\theta}}_{K\ensuremath{\pi}}=20\ifmmode^\circ\else\textdegree\fi{}$, momentum transfer $q=294$ Mev/c. Upper limits on formation cross sections are given and appear to rule out the existence of ${\ensuremath{\Sigma}}^{\ensuremath{-}}$ neutron bound states. In addition, a missing mass spectrum for the reaction $^{2}\mathrm{H}({K}^{\ensuremath{-}}{\ensuremath{\pi}}^{\ensuremath{-}})X$, ${\ensuremath{\theta}}_{K\ensuremath{\pi}}=4\ifmmode^\circ\else\textdegree\fi{}$, $q=134$ MeV/c ($X={\ensuremath{\Sigma}}^{+}n, {\ensuremath{\Sigma}}^{\ensuremath{\circ}}p, or \ensuremath{\Lambda}p$), is shown and discussed.NUCLEAR REACTIONS $\ensuremath{\Sigma}n$ mass spectrum $\ensuremath{\Sigma}$ neutron bound states, ($K$,$\ensuremath{\pi}$) reaction on deuterium, $\ensuremath{\Lambda}p$ mass spectrum.

The field of ring imaging (broad band differential) Cherenkov detectors has become a very active area of interest in detector development at several high energy physics laboratories. Our group has previously reported on a method of Cherenkov ring imaging for a counter with large momentum and angular acceptance using standard photo multipliers. Recently, we have applied this technique to the design...

The spectra of levels in the hypernuclei $_{\ensuremath{\Lambda}}^{13}\mathrm{C}$, $_{\ensuremath{\Lambda}}^{14}\mathrm{N}$, and $_{\ensuremath{\Lambda}}^{18}\mathrm{O}$, excited by 800-MeV/c kaons in the (${K}^{\ensuremath{-}}$,${\ensuremath{\pi}}^{\ensuremath{-}}$) reaction, have been observed at the Brookhaven alternating-gradient synchrotron. Data were recorded for scattering angles from 0\ifmmode^\circ\else\textdegree\fi{} to 25\ifmmode^\circ\else\textdegree\fi{}, corresponding to momentum transfers from 50 to 330 MeV/c. The levels are interpreted in terms of a $\ensuremath{\Lambda}$ hyperon coupled to a strangeness-zero nuclear core. The results provide insights into the properties of the $\ensuremath{\Lambda}$-nucleon and $\ensuremath{\Lambda}$-nucleus interactions.

Results of an experiment to measure the cross section for production of the D*/sup +/(D*/sup -/) in 200-GeV/c r/sup -/N interactions are reported. 78 +- 26 events are observed, corresponding to a D* production cross section ds/dy = 1.6 +- 0.5 mb at y = 0.

Results are reported of an experiment to measure the cross section for production of the ${D}^{{*}^{+}}$ (${D}^{{*}^{\ensuremath{-}}}$) in 200-GeV/c ${\ensuremath{\pi}}^{\ensuremath{-}}N$ interactions. We observe 78 \ifmmode\pm\else\textpm\fi{} 26 events corresponding to a ${D}^{*}$-production cross section $\frac{d\ensuremath{\sigma}}{\mathrm{dy}}=1.6\ifmmode\pm\else\textpm\fi{}0.5$ \ensuremath{\mu}b at $y=0$.

During the fall running period of 1979 our group was able to conclude our first and only major data taking run for E-567. Using the spectrometer shown in Figure l, we were able to accumulate data for the equivalent of 600 hrs. of stable running (400 GeV accelerator operation with one second spill and > 90% beam duty factor). During this time, we recorded approximately 8 x 107 events on 400 magnetic tapes. The integrated flux of pions on our 1.8 g/cm2 target of beryllium was ~ 1 x 1013 at a beam momentum of 200 GeV/c.

The authors report results of an experiment to measure the cross section for the reaction {pi}{sup -} + N {yields} D*{sup {+-}} X at 200 GeV/c. They observe a 2.7 standard deviation signal corresponding to a D* production cross section d{sigma}/dy = 1.0 {+-} 0.4 {mu}b at y = 0.

We have searched for production of charmed mesons in the reaction ..pi../sup -/ + N ..-->.. D*/sup -/ + X, D*/sup -/ ..-->.. ..pi../sup -/ + D/sup 0/, D/sup 0/ ..-->.. K/sup +/ + ..pi../sup -/ at a beam momentum of 10.5 GeV/c. We measure the cross section times branching ratio to be 7 +- 20 nb/nucleon.