Sensor noise in LISA Pathfinder

Laser frequency noise and its coupling to the optical test mass readout

verfasst von
LISA Pathfinder Collaboration , M. Armano, H. Audley, J. Baird, P. Binetruy, M. Born, D. Bortoluzzi, N. Brandt, E. Castelli, A. Cavalleri, A. Cesarini, A. M. Cruise, K. Danzmann, M. De Deus Silva, I. Diepholz, G. Dixon, R. Dolesi, L. Ferraioli, V. Ferroni, E. D. Fitzsimons, R. Flatscher, M. Freschi, A. García, R. Gerndt, L. Gesa, D. Giardini, F. Gibert, R. Giusteri, C. Grimani, J. Grzymisch, F. Guzman, I. Harrison, M. S. Hartig, G. Hechenblaikner, G. Heinzel, M. Hewitson, D. Hollington, D. Hoyland, M. Hueller, H. Inchauspé, O. Jennrich, P. Jetzer, U. Johann, B. Johlander, N. Karnesis, B. Kaune, C. J. Killow, N. Korsakova, J. A. Lobo, J. P. López-Zaragoza, G. Wanner, S. Paczkowski, Jens Reiche, L. Wissel, A. Wittchen

The LISA Pathfinder (LPF) mission successfully demonstrated the feasibility of the technology needed for the future space borne gravitational wave observatory LISA. A key subsystem under study was the laser interferometer, which measured the changes in relative distance in between two test masses (TMs). It achieved a sensitivity of 32.0-1.7+2.4 fm/Hz, which was significantly better than the prelaunch tests. This improved performance allowed direct observation of the influence of laser frequency noise in the readout. The differences in optical path lengths between the measurement and reference beams in the individual interferometers of our setup determined the level of this undesired readout noise. Here, we discuss the dedicated experiments performed on LPF to measure these differences with high precision. We reached differences in path length difference between (368±5) μm and (329.6±0.9) μm which are significantly below the required level of 1 mm or 1000 μm. These results are an important contribution to our understanding of the overall sensor performance. Moreover, we observed varying levels of laser frequency noise over the course of the mission. We provide evidence that these do not originate from the laser frequency stabilization scheme which worked as expected. Therefore, this frequency stabilization would be applicable to other missions with similar laser frequency stability requirements.

Institut für Gravitationsphysik
PhoenixD: Simulation, Fabrikation und Anwendung optischer Systeme
Institut für Quantenoptik
Externe Organisation(en)
European Space Research and Technology Centre (ESTEC)
Max-Planck-Institut für Gravitationsphysik (Albert-Einstein-Institut)
Observatoire de Paris (OBSPARIS)
Università degli Studi di Trento
Airbus Group
Istituto Nazionale di Fisica Nucleare (INFN)
Fondazione Bruno Kessler
Universität Urbino „Carlo Bo“
University of Birmingham
European Space Astronomy Centre
ETH Zürich
Royal Observatory
Hochschule Bremen
Universidad Autónoma de Barcelona (UAB)
Institut d'Estudis Espacials de Catalunya (IEEC)
Texas A and M University
Europäisches Raumflugkontrollzentrum (ESOC)
Imperial College London
Ruprecht-Karls-Universität Heidelberg
Universität Zürich (UZH)
University of Glasgow
Physical Review D
ASJC Scopus Sachgebiete
Kern- und Hochenergiephysik
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