Thermal Diagnostics in the LISA Technology Package Experiment

Abstract

LISA Pathfinder (LPF) is an ESA mission, with NASA contributions, devoted to pave the way to the future spaceborne gravitational wave observatory LISA. The LISA Technology Package (LTP) experiment in the LPF mission will measure the differential acceleration between two free falling test masses to the picometer resolution by using both masses as end mirrors of an interferometer, together with an active control loop, known as drag-free, that will act to keep the spacecraft centred around the geodesic motion of the masses. The work in this thesis deals with the thermal diagnostic subsystem, intended to measure and characterise the thermal noise contribution to the instrument performance: from the qualification of the high stability electronics designed to measure temperature fluctuations in the millihertz bandwidth to the definition of heaters, aimed to generate controlled perturbations during mission operations. The results obtained characterise the temperature subsystem and define a first step towards a methodology to deal with the thermal data that will be obtained during flight operations.