Spectral Representation of Multivariate Regularly Varying Lévy and CARMA Processes

A spectral representation for regularly varying Lévy processes with index between one and two is established and the properties of the resulting random noise are discussed in detail, giving also new insight in the L ²-case where the noise is a random orthogonal measure. This allows a spectral definition of multivariate regularly varying Lévy-driven continuous time autoregressive moving average (CARMA) processes. It is shown that they extend the well-studied case with finite second moments and coincide with definitions previously used in the infinite variance case when they apply.     

Updated status of the global electroweak fit and constraints on new physics

We present an update of the Standard Model fit to electroweak precision data. We include newest experimental results on the top-quark mass, the W mass and width, and the Higgs-boson mass bounds from LEP, Tevatron and the LHC. We also include a new determination of the electromagnetic coupling strength at the Z pole. We find for the Higgs-boson mass $91^{+30}_{-23}~\mbox{GeV}$ and $120^{+12}_{-5}~\mbox{GeV}$ when not including and including the direct Higgs searches, respectively. From the latter fit we indirectly determine the W mass to be $(80.360^{+0.014}_{-0.013})~\mbox{GeV}$ . We exploit the data to determine experimental constraints on the oblique vacuum polarisation parameters, and confront these with predictions from the Standard Model (SM) and selected SM extensions. By fitting the oblique parameters to the electroweak data we derive allowed regions in the BSM parameter spaces. We revisit and consistently update these constraints for a fourth fermion generation, two Higgs doublet, inert Higgs and littlest Higgs models, models with large, universal or warped extra dimensions and technicolour. In most of the models studied a heavy Higgs boson can be made compatible with the electroweak precision data.     

The Resting State Makes the Difference: The Influence of the Anchor Group in the ROMP of Norbornene Derivatives

Summary: A model study with four norbornene derivatives with different groups connecting a functional unit to the norbornene reveals that the “anchor groups” influence the polymerisation rate constants of ring opening metathesis (ROM) polymerisations. Consequently, polydispersities and molecular weights are affected. The observed effects are explained by different tendencies of the anchor groups to coordinate to the ruthenium centre during the resting state of the propagation.

A functionalised monomer where F is the functional unit, S is a spacer, A is an anchor group and P is the polymerisable group.     

Neuartige chelatringsysteme: 1,4-h2-komplexe des linearen hexamethyltetraphosphins me2 pPmePmePme2 und bis(1, 2-dimethylphosphino)-i,2-dimethyldlarsins me2 PAsMeA sM ePMe2.

Reaction of methyldichloro-phosphine or -arsine with the dilithium salt cis-Mo(CO)₄ (PMe₂ Li)₂ affords complexes of the linear hexamethyltetraphosphine or bis(1,2-dimethylphosphino)-l,2-dimethyldiarsine.     

Neutron multiplicities in inelastic collisions of132Xe with197Au

The multiplicities of neutrons emitted from the light and heavy fragments, respectively, in the inelastic scattering of 7.5 MeV/amu¹³² Xe ions from¹⁹⁷Au have been studied as a function of total energy loss. The measured multiplicity ratios are close to the Au-Xe mass ratio for all Q-values, consistent with a rapid thermalization of the excitation energy. The absolute multiplicity values are lower than expected and suggest significant pre-equilibrium effects.     

Reaktionen koordinierter Liganden. XVI. Struktur von Lithiumphosphido-Komplexen cis-Mo(CO)4(PRR′Li)2(R,R′  H,Alkyl, Aryl) in Lösung – eine 31P- und 7Li-NMR-spektroskopische Studie

Reactions of Coordinated Ligands. XVI. Structure of the Lithiumphosphido Complexes cis-Mo(CO)₄(PRR′Li)₂ (R, R′ ? H, Alkyl, Aryl) in Solution – a ³¹P and ⁷Li N.M.R. Study Complexes of the lithiumorganophosphides cis-Mo(CO)₄(PRR′Li)₂ (R, R′ ? H, Alkyl, Aryl) may be assigned to a ionic type (solvated) of structure [cis-Mo(CO)₄(PRR′)₂Li]^?Li⁺ in solution. According to ⁷Li and ³¹P NMR measurements at low temperatures the anion comprises a four membered MoP₂Li ring system. The temperature dependence of the ⁷Li and ³¹P NMR spectra may be explained by an intermolecular Li exchange and inversion of configuration at the phosphorus atoms.     

η3:η1⇌η2-tautomerism in carbonyliron complexes. Influence of substituents

A number of chelate η³-allylcarbamoyl iron complexes (I) with different substituents (R in the allyl ligand and R′ at the nitrogen atom) were synthesized. The influence of structural features on the equilibrium between the complexes I and their η²-azadiene tautomers (II) was studied by IR spectroscopy. It was established that the equilibrium position is determined in the first place by steric factors. When R is a bulky substituent the equilibrium is shifted towards the cyclic form I, whereas the branching of the alkyl substituent R′ at the nitrogen atom favours the open olefinic form II. Furthermore π-σ-(N) rearrangement of complexes II to σ-(N) derivatives (III), and the conversion of III into η⁴-azadiene complexes (IV) also depend on the steric requirements of the substituents R and R′.