[en] High-spin states in ⁷⁸Br which decay into the previously known 4sup(+) isomer at 180.8 keV were observed using the ⁷⁷Se(α,2np) reaction. Two new isomeric states of 9 +- 1 ns at 337.8 keV ad 84 +- 8 ns at 227.6 keV are reported. (author)

[en] Λ⁰ polarization from pp → p_diffractedΛ⁰K⁺at 800 GeV/c in the average depends linearly on Λ⁰K⁺ invariant mass: Λ⁰ polarization is 0.635 ± 0.036 at 1.64 GeV, consistent with zero at ∼ 2.195 GeV, and -0.586 ± 0.072 at 3.200 GeV. The origin of this ^Λ0 polarization is, probably, the interference of at least two Λ⁰K⁺ resonances, created from the excitation of the target proton, due to the diffracted proton transferred momentum

[en] Results are presented of the spin-parity analysis on a sample of centrally produced mesons in the reaction pp → p_slow(K_sK_s)p_fast with 800 GeV protons on liquid hydrogen. The spin-parity analysis in the mass region between threshold and 1.58 GeV/c² shows that the K_sK_s system is produced mainly in S wave. The f₀(1500) is clearly observed in this region. Above 1.58 GeV/c² two solutions are possible, one with mainly S wave and another with mainly D wave. This ambiguity prevents a unique determination of the spin of the f_J(1710) meson. 9 refs., 6 figs

[en] In an effort to study the effect of the entrance channel mass asymmetry on the fusion process at near-barrier energies, we have measured the fusion cross section and its distribution according to the different evaporation residues for the ²⁸Si+¹⁴²Ce, ³²S+¹³⁸Ba, and ⁴⁸Ti+¹²²Sn systems. All these systems lead to the same compound nucleus ¹⁷⁰Hf. The measurements were performed using a delayed x-ray technique. For the last two systems we have also measured the fission cross sections in the same bombarding energy range. This experimental information can be used to restrict the free parameters of the statistical model used to account for the relative yield. A constrained and realistic statistical decay model is useful in reducing the uncertainties in the determination of the spin distribution from measurements of gamma multiplicities for these systems. The excitation function for the fusion cross section can be described using a schematic coupled channels calculation with realistic coupling strengths. Our results show no umambiguous effect that can be associated with the entrance channel mass asymmetry

[en] Fusion cross sections and gamma ray multiplicities have been measured for the ²⁸Si+¹⁴²Ce, ³²S+¹³⁸Ba, and ⁴⁸Ti+¹²²Sn entrance channels leading to the ¹⁷⁰Hf compound nucleus. The mean spins deduced from the gamma multiplicities do not show any anomalous behavior as observed in some other measurements

[en] Results are presented from a partial wave analysis of a sample of centrally produced mesons in the reaction pp→p_slow(K_sK_s)p_fast, with 800 GeV/c protons incident on a liquid hydrogen target. The meson system is found to be predominantly S-wave in the mass range between K_sK_s threshold and 1.58 GeV/c². The f₀(1500) is clearly observed in this region. Above 1.58 GeV/c² two solutions are possible, one with mainly S-wave and another with mainly D-wave. This ambiguity prevents a unique determination of the spin of the f_J(1710) meson. copyright 1998 American Institute of Physics

[en] Partial wave analysis results of centrally produced mesons in the reaction pp→p_slow(X)p_fast, with 800 GeV/c protons incident on a liquid hydrogen target are presented. In the reactions considered in this paper the (X) system decays into: a) K_a⁰K^±π^minus-plus, b) K_sK_s, and c) π⁺π^-. copyright 1998 American Institute of Physics

[en] Results are presented from a partial wave analysis of a sample of centrally produced mesons in the reaction pp→p_slow(K_SK_S )p_fast , with 800 GeV/c protons incident on a liquid hydrogen target. The meson system is found to be predominantly S wave in the mass range between K_SK_S threshold and 1.55 GeV/c² . The f₀(1500) is observed in this region. Above 1.55 GeV/c² two solutions are possible, one with mainly S wave and another with mainly D wave. This ambiguity prevents a unique determination of the spin of the f_J(1710) meson. copyright 1998 The American Physical Society

[en] Results are presented from an analysis of a large sample of centrally produced mesons in the reaction pp→p_slow(K⁰_S K^±π^minus-plus)p_fast with 800 GeV/c protons incident on liquid hydrogen. Two resonances dominate the final state, the f₁(1285) , decaying into a₀π , and the f₁(1420) , decaying into K^*K . Both mesons are produced with equal amounts of |J_z|^η=1^± , and no J_z=0 . copyright 1999 The American Physical Society

[en] We report results from a study of Λ⁰ polarization in the exclusive reaction pp→p_f(Λ⁰K⁺ ) at 800-GeV/c . We observe a dependence of the polarization on the Λ⁰K⁺ invariant mass with large (+71%) positive polarization at small mass (1.63-GeV/c² ) and large (-43%) negative polarization at large mass (2.75-GeV/c² ) . This observation confirms the result of the CERN ISR R608 experiment and extends the range over which the effect is observed. The strong dependence of the polarization on the Λ⁰K⁺ invariant mass suggests that the origin of the polarization is closely related to the production dynamics of the diffractively produced Λ⁰K⁺ system