Michael Peterseim

Angular resolution of LISA

LISA is a space-borne, laser-interferometric gravitational wave detector currently under study by the European Space Agency. We give a brief introduction about the main features of the detector, concentrating on its one-year orbital motion around the Sun. We show that the amplitude as well as the phase of a gravitational wave is modulated due to that motion, allowing us to extract information from the signal. The most common way to estimate the parameters which characterize a signal present in a noisy data stream is to use the matched filtering technique. A brief review of the theory of parameter estimation, based on the work of Finn and Cutler, will be given. We carried out a simulation of the detection of a monochromatic gravitational wave based on that theory and focusing on estimating the angular parameters of the source. The results of the semi-analytic calculations are presented in detail and interpreted to determine the angular resolution of LISA.

LISA interferometer sensitivity to spacecraft motion

A study has been performed to assess the sensitivity of the LISA interferometer to motion of the spacecraft (S/C) with respect to the proof mass. The results are presented as a functions of arm length and Fourier frequency. In addition different optical arrangements have been analysed and their effects on the cancellation of the spacecraft motion is discussed. 0 2000 COSPAR. Published by Elsevier Science Ltd. ANALYSIS OF INTERFEROMETER RESPONSE TO S/C MOTION The approach used in this study, starting with the optical arrangement of the current LISA baseline as outlined by Danzmann et al. (1997 and 1998), was to calculate the phase information detected with the individual photodiodes mounted onto the different optical benches. Methods were defined to extract the gravitational wave signal contained in this phase information by removing laser phase noise as well as noise due to the S/C motion. In this section the phase information recorded on the photodiodes is described. The following sections deal with the different data acquisition and data analysis methods, including signal extraction algorithms and possible modifications to the current optical arrangement.

Accuracy of parameter estimation of gravitational waves with LISA

LISA is a space-borne, laser-interferometric gravitational-wave detector currently under study by the European Space Agency. We give a brief introduction about the main features of the detector, concentrating on its one-year orbital motion around the Sun. We compute how the amplitude as well as the phase of a gravitational wave are modulated due to this motion by transforming an arbitrary gravitational-wave signal in a reference frame that is rigidly fixed to the arms of the detector. To see how LISA works the detector response to a gravitational wave which is purely monochromatic in the barycentric frame will be discussed. A brief review of the theory of parameter estimation, based on the work of Finn and Cutler, will be given. Following this theory the detection of a gravitational-wave signal buried in detector noise was simulated numerically. We interpret the results of this simulation to determine the angular resolution of LISA.

The laser system for the LISA technology demonstrator

Future space science missions rely on qualified interferometric position and length measurement technology. Laser metrology is one of the key issues. We describe the laser system for the LISA technology demonstrator. This laser system consists of a laser-diode pumped monolithic non-planar Nd:YAG ring laser with a design optimised to withstand the severe space environment.

Laser development and laser stabilization for the space-borne gravitational wave detector LISA

For the interferometric readout of the 107 km optical path length, the LISA mission will rely on a compact, reliable and highly efficient source of stable radiation. The strain sensitivity of the instrument will be limited by photon shot noise in the mHz frequency regime and therefore an output power of at least 1 W is required. The noise added by power and frequency fluctuations of the laser is negligible only for a relative power stability of δP/P<2×10−4/Hz and for a frequency noise spectral density of <30 Hz/Hz within the LISA detection band. The only light source approaching the performance demanded for LISA is a stabilized monolithic diode pumped Nd:YAG ring laser. We report on recent progress in designing and stabilizing this laser type for the LISA mission.

Position determination of gravitational wave sources with LISA

LISA is a spaceborne laser interferometer for the detection and observation of gravitational waves, currently under study by ESA. A brief introduction of the main features of this detector, concentrating on its oneyear orbital motion around the Sun is given. The amplitude as well as the phase of a gravitational wave is modulated due to that motion, allowing us to extract information from the signal. The detection of monochromatic gravitational waves based on the well-known signal detection theory is simulated, focusing on estimating the angular parameters of the source. The results of the semi-analytic calculations give the angular resolution of LISA.

Measuring a binary's orientation with LISA

Abstract We are presenting numerical results concerning LISAs ability to distinguish between different polarizational states of a gravitational wave. Therefore, we assume a binary as a source of a gravitational wave, finding its orientation which determines the polarization of the gravitational wave. By means of signal processing, we are able to give the 1σ-uncertainty for determining the orientation of the source.

Ultra-stable solid-state lasers for space applications

Summary form only given. We report about the development of a space qualified laser system based on a monolithic non-planar Nd:YAG ring oscillator (NPRO). The system can be used for space applications such as a satellite-based LIDAR (Light Induced Detection and Ranging) measurement of wind velocities, a gravitational wave detector in space (LISA) or coherent inter satellite communication. The laser can be used as a seed laser for a resonant or non-resonant high power amplification (e.g. for LIDAR) or as a master oscillator with an output power up to 3.5 W in the case of the LISA project.

Polarization resolution of LISA

We discuss LISAs ability to resolve different polarizational states of a gravitational wave with fixed frequency and amplitude. Assuming a binary as the source of the gravitational wave, its orientation is connected with the polarization of the gravitational wave emitted. Using methods of signal processing, we calculate the 1- uncertainty range for measuring the orientation of the source.