Subtraction of test mass angular noise in the LISA Technology Package   interferometer
  We present recent sensitivity measurements of the LISA Technology Package interferometer with articulated mirrors as test masses, actuated by piezo-electric transducers. The required longitudinal displacement resolution of 9 pm/sqrt[Hz] above 3 mHz has been demonstrated with an angular noise that corresponds to the expected in on-orbit operation. The excess noise contribution of this test mass jitter onto the sensitive displacement readout was completely subtracted by fitting the angular interferometric data streams to the longitudinal displacement measurement. Thus, this cross-coupling constitutes no limitation to the required performance of the LISA Technology Package interferometry. 
Felipe Guzm\'an Cervantes, Frank Steier, Gudrun Wanner, Gerhard   Heinzel, Karsten Danzmann
astro-ph.IM gr-qc physics.ins-det physics.optics physics.space-ph