Charged particle spectra in αα and αp collisions at the CERN ISR

Momenta of charged particles produced in inelastic αα, αp, andpp collisions were measured using the Split-Field-Magnet detector at the CERN Intersecting Storage Rings. Inclusive and semi-in-clusive spectra are presented as a function of rapidityy, Feynman-x, and transverse momentump _T . The inclusivey distributions agree well with predictions of the dual parton model; the highest particle densities are reached aty?0 and the momenta of leading protons decrease significantly for increasing total multiplicity. ‘Temperatures’ are equal in αα, αp, andpp interactions. Thep _T distributions depend weakly on the multiplicity.     

μSR studies of the metallic alkali fullerides

We report ZF μSR measurements in Cs₁C₆₀ at low temperature and LF μSR in the superconductor Rb₃C₆₀. In Cs₁C₆₀, the internal magnetic field distribution is broad and static, and the relaxation at 1.9 K resembles that of a spin density wave. In Rb₃C₆₀, we observe a strong field dependence to the coherence peak in the LF relaxation rate of endohedral muonium ( Mu@C₆₀) at anomalously low field and a residual low temperature relaxation. This revised version was published online in August 2006 with corrections to the Cover Date.     

Photolactonisierung: Ein neuer synthetischer Zugang zu Makroliden

Photolactonization: A Novel Synthetic Entry to Macrolides o-Quinol acetates, hydroxyalkylated at C(6), are easily accessible from simple phenols by Wessely acetoxylation (preferentially catalyzed by BF₃). On UV irradiation (in the presence of an appropriate tertiary amine), they are smoothly converted to macrocyclic lactones. Subtle conditions have been elaborated to lead to high overall yields, and the scope of the conversion of phenols to macrolides has been elucidated.     

Phonon freedom and confinement in GaAsAlxGa1−xAs superlattices

Phonon modes in GaAsAl_xGa_1?xAs superlattices simplify when the phonon wavevector q is perpendicular to the plane of the layers. We have studied such modes using a Raman back-scattering technique on SL's grown by MBE. The results are consistent with simple ideas of LA phonon freedom and LO phonon confinement suggested by one-dimensional lattice dynamical calculations. The longitudinal acoustic (LA) modes show zone folding due to mini-zone formation. Their frequencies occur in doublets linearly dependent on q and show little mini-gap formation. This is consistent with a picture of approximately free plane wave propagating through the interfaces with Raman coupling due to SL layering of the photoelastic coefficient. By contrast, Raman data on LO modes in small period GaAsAlAs SL's suggest that these modes are standing waves strongly confined in either GaAs or AlAs.     

Hydrogen in metane: Prediction of Henry's constants from pure-component properties only

Fischer. J., Bohn, M. and Gebauer, M., 1984. Hydrogen in methane: prediction of Henrys constants from pure-component properties only. Fluid Phase Equilibria, 17: 131-133.The prediction of gas solubilities in liquids from pure substance properties seems possible for molecularly simple components by using perturbation theory and Kohiers combining rule. This is demonstrated by calculating Henrys constants for the system hydrogen/methane.     

Nuclear stopping power in αα anddd collisions

Inelasticαα anddd collisions were studied at a centre-of-mass energy √S _NN=31.2 GeV per nucleon-nucleon collision, using the Split-Field Magnet (SFM) detector at the CERN ISR. In this paper we show the inclusive and semi-inclusive rapidity distributions of protons, compare them with predictions of the Lund model, and calculate the average rapidity loss for participant protons. From the negative particles we calculate the inelasticity of the interaction, the average energy per particle, and the degree of isotropy of the produced hadrons.