Non-linear parameter estimation for the LTP experiment: analysis of an operational exercise

G. Congedo; F. De Marchi; L. Ferraioli; M. Hueller; S. Vitale; M. Hewitson; M. Nofrarias; A. Monsky; M. Armano; A. Grynagier; M. Diaz-Aguilo; E. Plagnol; B. Rais

arXiv · 1108.0865

Non-linear parameter estimation for the LTP experiment: analysis of an operational exercise

G. Congedo·F. De Marchi·L. Ferraioli·M. Hueller·S. Vitale·M. Hewitson·M. Nofrarias·A. Monsky·M. Armano·A. Grynagier·M. Diaz-Aguilo·E. Plagnol·B. Rais

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Abstract

The precursor ESA mission LISA-Pathfinder, to be flown in 2013, aims at demonstrating the feasibility of the free-fall, necessary for LISA, the upcoming space-born gravitational wave observatory. LISA Technology Package (LTP) is planned to carry out a number of experiments, whose main targets are to identify and measure the disturbances on each test-mass, in order to reach an unprecedented low-level residual force noise. To fulfill this plan, it is then necessary to correctly design, set-up and optimize the experiments to be performed on-flight and do a full system parameter estimation. Here we describe the progress on the non-linear analysis using the methods developed in the framework of the \textit{LTPDA Toolbox}, an object-oriented MATLAB Data Analysis environment: the effort is to identify the critical parameters and remove the degeneracy by properly combining the results of different experiments coming from a closed-loop system like LTP.

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G. Congedo, F. De Marchi, L. Ferraioli, M. Hueller, S. Vitale, M. Hewitson, M. Nofrarias, A. Monsky, M. Armano, A. Grynagier, M. Diaz-Aguilo, E. Plagnol, B. Rais. 2011-08-03. Non-linear parameter estimation for the LTP experiment: analysis of an operational exercise. https://arxiv.org/abs/1108.0865

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