Strong coupling 1/N c expansion in the gluonic sector of lattice QCD: The next order

Continuing our previous work we determined the gluonic vacuum state up to sixth order and the lowest states with external quark-antiquark and (unscreened) gluon-gluon sources up to fourth order in the strong coupling 1/N _c expansion on the lattice. Unlike previously, we used here the colour electric flux operators on the links to define the colour electric energy. Additional remarks concerning the screening of external gluon sources and the analytic continuation toN _c =3 and zero lattice spacing are also included.     

Zum Einfluß der Halogenmodifizierung auf das acide Verhalten von γ-Al2O3

Influence of Modification of γ-Alumina by Halides on the Acidic Behaviour The influence of modification of γ-alumina by Cl and F on the acidic properties was studied by means of i.r. spectroscopic methods using ammonia as probe molecule. The measurements show a significant rise in Lewis acidity.     

The high-temperature behaviour of lattice QCD with fermions

By Monte Carlo simulation on the lattice, we calculate the high-temperature behaviour of the energy density ? in SU(2) and SU(3) QCD with Wilson fermions. From the leading term of the hopping parameter expansion, we find that ? converges very rapidly to the Stefan-Boltzmann limit of an asymptotically free quark-gluon gas. The behaviour in the non-asymptotic region indicates that chiral symmetry restoration occurs at a higher temperature (T_ch) than colour deconfinement (T_c), with $\text{T}{}_{\mathrm{<mtext>ch</mtext>}}\text{T}{}_{\mathrm{<mtext>c</mtext>}}\text{≈ 1.3}$.     

Untersuchungen an Metallkatalysatoren. Zur Dispersit?t von Pt-Ir-Katalysatoren

Ohne Zusammenfassung     

The size of Bose-Einstein effects in the statistical bootstrap model

We have determined the shift in Hagedorn temperature due to Bose statistics and calculated explicitly the cluster expansions of fireball level densities. This enabled us to investigate Bose effects in one-particle spectra and integrated correlations. Apart from the low secondary energy region of the one-particle distributions, the nonasymptotic behaviour of these quantities is little affected.     

The energy dependence of single particle spectra in e+e− annihilation

We present explicit predictions of the statistical bootstrap model for inclusive single particle spectra in e⁺e^? annihilation. The distribution (ω/σ_tot·E) (dσ/p² dp) is found to become, for E ? 3 GeV, a function only of the secondary energy ω, independent of the incident e⁺d^? energy E.