Spectral properties of dissipative chaotic quantum maps

I examine spectral properties of a dissipative chaotic quantum map with the help of a recently discovered semiclassical trace formula. I show that in the presence of a small amount of dissipation the traces of any finite power of the propagator of the reduced density matrix, and traces of its classical counterpart, the Frobenius-Perron operator, are identical in the limit of variant Planck's over 2pi -->0. Numerically I find that even for finite variant Planck's over 2pi the agreement can be very good. This holds in particular if the classical phase space contains a strange attractor, as long as one stays clear of bifurcations. Traces of the quantum propagator for iterations of the map agree well with the corresponding traces of the Frobenius-Perron operator if the classical dynamics is dominated by a strong point attractor. (c) 1999 American Institute of Physics.     

CLASS: A Comprehensive Satellite Link Simulation Package

CLASS (communication link analysis and simulation system) is a software package developed for NASA to predict the communication and tracking performance of the tracking and data relay satellite system (TDRSS) services. This paper describes the capabilities of CLASS and the communication link model used, and discusses typical applications for CLASS.     

Valence bands of silver halides determined by X-ray and UV photoemission

Photoemission from AgCl, AgBr, and AgI has been studied at photon energies hω = 16.8, 21.2, 26.9, 40.8, 48.4 and 1486.6 eV. By exploiting the strong     

On the nuclear density distribution for nucleus-nucleus scattering. II

We investigate the effect of the antisymmetrization on the density distribution for nucleus-nucleus scattering. In contrast to an earlier paper¹ the motion of the nuclei is now taken into account. For experimentally available energies we find no pronounced density compression in the overlap region. For very high energies a superposition of the densities is justified.     

Arch?ometrische Untersuchungen von r?mischen Ziegeln und Wandplatten

Zusammenfassung Am Beispiel von Ziegel- und Wandplattenbruchstücken einer römischen Wüstung bei Schwarzenholz (Saarland) wird die Auswertung der Analysendaten und der Ergebnisse von Schnittbetrachtungen vorgestellt. Als geeignete Analysenverfahren erweisen sich die Röntgenfluorescenzanalyse und die Atomabsorptionsspektralanalyse. Mit Hilfe der Taxometrie gelingt eine Einteilung der Bruchstücke in die Gruppen Örtliches Material, Blickweiler und Gestempeltes Material. Die Untersuchungsergebnisse gestatten die Bestimmung des mengenmäßigen Anteils verschiedener Produktionen für einen Fundplatz und erlauben somit dem Archäologen Aussagen über wirtschaftliche Zusammenhänge.Für finanzielle Unterstützung danken wir der Stiftung Volkswagenwerk, Hannover.     

Displacement substoichiometric separations in radioanalytical chemistry

The principle of displacement substoichiometry and the possibilities of its practical use have been outlined. The substoichiometric separation of lead, arsenic, and zinc can be carried out by applying diethyldithiocarbamate complexes and solvent extraction.     

Analysis of repetitive mechanism signatures

A new signal decomposition for repetitive signatures is introduced. This is based on the concept of derived time series, produced by rearranging the original signal by using points one period apart. Time domain averaging is shown to be a special case of such rearrangement, and a second technique of variance analysis is presented. Applications to rotating machinery show that the decomposition can be very sensitive to various generating mechanisms, making them suitable for signature analysis of mechanical systems.