Dynamics of metal centers monitored by nuclear inelastic scattering

Nuclear inelastic scattering of synchrotron radiation has been used now since 10 years as a tool for vibrational spectroscopy. This method has turned out especially useful in case of large molecules that contain a Mössbauer active metal center. Recent applications to iron–sulfur proteins, to iron(II) spin crossover complexes and to tin-DNA complexes are discussed. Special emphasis is given to the combination of nuclear inelastic scattering and density functional calculations.     

A strongly degenerate diffusion equation with strong absorption

It is shown that the Cauchy problem in ? for the strongly degenerate parabolic equation $$ u_t = u^p u_{xx} - u^{-q} \chi _{ \{u>o \} }\, , \quad p \ge 1 \, , \quad q > -1 \, , $$ has a nonnegative weak solution for any nonnegative bounded continuous initial datum, provided that q ≤ p – 1, while there is no (continuous) weak solution for q > p – 1. The evolution of the spatial positivity set {u(t) > 0}, continuity of the free boundary and the extinction rate are also investigated. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)     

Nitrat

Ohne Zusammenfassung     

A new experimental approach for isochronous mass measurements of short-lived exotic nuclei with the FRS-ESR facility

Projectile fragments separated in flight with the FRS have been injected into the storage ring ESR. Operating the ESR in the isochronous mode has enabled high-resolution mass measurements of short-lived isotopes. Already in our pilot experiments the Isochronous Mass Spectrometry (IMS) has provided accurate results for a restricted isotope range in the neighborhood of a selected isotope characterized by the best isochronous condition. In the present experiment this restriction has been overcome by precise external magnetic rigidity determination (1.5·10^–4) at the dispersive midplane of the FRS. In this way the mass resolving power for neutron-rich fission fragments covering a large mass-over-charge ratio in one spectrum has been improved by up to one order of magnitude and the accuracy by more than a factor of two.     

De Branges Spaces of Entire Functions Symmetric About the Origin

We define and investigate the class of symmetric and the class of semibounded de Branges spaces of entire functions. A construction is made which assigns to each symmetric de Branges space a semibounded one. By employing operator theoretic tools it is shown that every semibounded de Branges space can be obtained in this way, and which symmetric spaces give rise to the same semibounded space. Those subclasses of Hermite-Biehler functions are determined which correspond to symmetric or semibounded, respectively, nondegenerated de Branges spaces. The above assignment is determined in terms of the respective generating Hermite-Biehler functions.     

Zur Chlorometrie

Ohne Zusammenfassung     

Ueber die Graphit-Thermometer und -Pyrometer

Ohne Zusammenfassung     

Measurement of the beta+ and orbital electron-capture decay rates in fully ionized, hydrogenlike, and heliumlike 140Pr ions

We report on the first measurement of the beta+ and orbital electron-capture decay rates of 140Pr nuclei with the simplest electron configurations: bare nuclei, hydrogenlike, and heliumlike ions. The measured electron-capture decay constant of hydrogenlike 140Pr58+ ions is about 50% larger than that of heliumlike 140Pr57+ ions. Moreover, 140Pr ions with one bound electron decay faster than neutral 140Pr0+ atoms with 59 electrons. To explain this peculiar observation one has to take into account the conservation of the total angular momentum, since only particular spin orientations of the nucleus and of the captured electron can contribute to the allowed decay.