Upper limits on the strength of periodic gravitational waves from PSR J1939+2134

The first science run of the LIGO and GEO gravitational wave detectors presented the opportunity to test methods of searching for gravitational waves from known pulsars. Here we present new direct upper limits on the strength of waves from the pulsar PSR J1939+2134 using two independent analysis methods, one in the frequency domain using frequentist statistics and one in the time domain using Bayesian inference. Both methods show that the strain amplitude at Earth from this pulsar is less than a few times $10^{-22}$.Comment: 7 pages, 1 figure, to appear in the Proceedings of the 5th Edoardo Amaldi Conference on Gravitational Waves, Tirrenia, Pisa, Italy, 6-11 July 200

Improving the sensitivity to gravitational-wave sources by modifying the input-output optics of advanced interferometers

We study frequency dependent (FD) input-output schemes for signal-recycling interferometers, the baseline design of Advanced LIGO and the current configuration of GEO 600. Complementary to a recent proposal by Harms et al. to use FD input squeezing and ordinary homodyne detection, we explore a scheme which uses ordinary squeezed vacuum, but FD readout. Both schemes, which are sub-optimal among all possible input-output schemes, provide a global noise suppression by the power squeeze factor, while being realizable by using detuned Fabry-Perot cavities as input/output filters. At high frequencies, the two schemes are shown to be equivalent, while at low frequencies our scheme gives better performance than that of Harms et al., and is nearly fully optimal. We then study the sensitivity improvement achievable by these schemes in Advanced LIGO era (with 30-m filter cavities and current estimates of filter-mirror losses and thermal noise), for neutron star binary inspirals, and for narrowband GW sources such as low-mass X-ray binaries and known radio pulsars. Optical losses are shown to be a major obstacle for the actual implementation of these techniques in Advanced LIGO. On time scales of third-generation interferometers, like EURO/LIGO-III (~2012), with kilometer-scale filter cavities, a signal-recycling interferometer with the FD readout scheme explored in this paper can have performances comparable to existing proposals. [abridged]Comment: Figs. 9 and 12 corrected; Appendix added for narrowband data analysi

Ultraschnelle lasergetriebene Protonendynamik in Gas- und Kondensierter Phase

Titlepage and TOC 1\. Introduction 1 2\. Theory 9 3\. Applications and Results 61 4\. Summary and Outlook 173 A. Appendix 177 Bibliography DanksagungIn this work different models for the treatment of laser driven, multidimensional intramolecular proton dynamics in gas phase and dissipative surroundings are examined. First the method of the "Cartesian Reaction Surface" (CRS) Hamiltonian and its derivation from ab initio data is presented. This approximation allows the modeling and calculation of potential energy surfaces for the nuclear motion of larger molecular systems in full dimensionality. The solution of the Schrödinger equation for this operator is then calculated via the "Multi Configuration Time Dependent Hartree" (MCTDH) method, which is especially suited for calculations dealing with systems of high dimensionality. The dissipative effects were modeled within perturbation theory with the Redfield approach. In addition to that the solvent was simulated using classical molecular dynamics, to determine the interaction of the bath with the CRS Hamiltonian. Using these numerical methods for the quantum dynamics, different control strategies for the proton transfer, using ultra-short laser pulses are compared. To this end, model systems, which were fitted to ab initio data, were calculated isolated and in condensed phase with dissipation. The control methods used range from fitting the parameters of analytical pulses in a simple two pulse pump-dump model, to parameter fits with genetic algorithms and local control schemes for the electrical field, and up to the application of optimal control theory.In dieser Arbeit werden verschiedene Methoden der Behandlung des multidimensionalen, lasergetriebenen intramolekularen Protonentransfers in Gasphase und dissipativer Umgebung untersucht. Dabei wird zuerst die Methodik des "Cartesian Reaction Surface" (CRS) Hamilton-Operators und seine Herleitung aus ab initio Daten dargestellt. Dieser Ansatz erlaubt die näherungsweise Berechnung von Potentialenergieflächen für die Kernbewegung größerer molekularer Systeme in vollständiger Dimensionalität. Zur Lösung der durch diesen Operator definierten Schrödinger Gleichung wird die für hochdimensionale Systeme besonders geeignete "Multi Configuration Time Dependent Hartree" (MCTDH) Methode genutzt. Zur Einbeziehung dissipativer Effekte wurde das Lösungsmittel störungstheoretisch mit Hilfe der Redfield Theorie modelliert. Zusätzlich wurde das Bad durch klassische Molekulardynamik-Simulationen untersucht, um direkt den Einfluss eines klassisch behandelten Lösungsmittels auf den CRS Hamiltonoperator zu bestimmen. Mit Hilfe dieser numerischen Methoden zur Berechnung der Quantendynamik wurden verschiedene Strategien zur Kontrolle des Protonentransfers durch ultrakurze Laserpulse verglichen. Dazu werden Modellsysteme, die an ab initio Daten angepasst wurden, sowohl isoliert als auch in kondensierter Phase mit Dissipation untersucht. Die Kontrollmethoden die benutzt wurden, reichen von der Parameteranpassung analytischer Pulse in einem zwei Puls Pump-Dump Modell über die Parameteroptimierung durch genetische Algorithmen und lokale Kontrollstrategien für das elektrische Feld bis zur Anwendung der Theorie zur optimaler Kontrolle

Merlin cluster - report for the BAR

This is the report to the BAR that contains the design specifications for the cluster that the GEO data analysis group at the AEI is planning to build in order to perform searches for continuous gravitational wave signals

MuPAD User's Manual

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