Welcome to the 10th International LISA Symposium

LISA Pathfinder, the second of the European Space Agency's Small Missions for Advanced Research in Technology (SMART), is a dedicated technology validation mission for future interferometric spaceborne gravitational wave observatories, e.g. eLISA. LISA Pathfinder essentially mimics one arm of the eLISA constellation by shrinking the 1 million kilometre armlength down to a few tens of centimetres, giving up the sensitivity to gravitational waves, but keeping the measurement technology: the distance between the two test masses is measured using a laser interferometric technique similar to one aspect of the eLISA interferometry system. With the LISA Pathfinder launch date rapidly approaching (mid-2015), focus of the development has shifted from hardware procurement, to integration and testing. In addition, the ground segment is currently undergoing end-to-end system testing in preparation for the science operations phase of the mission. Here I will present an overview of the mission, focusing on scientific and technical goals, followed by the current status of the project.

Establishing a gravitational wave astrophysics observatory in space requires precise measurement of the relative accelerations between free-falling test particles, with sub-femto-g/Hz$^{1/2}$~resolution at mHz frequencies. LISA Pathfinder (LPF) will measure the differential acceleration between two test masses inside a single co-orbiting spacecraft, with an expected resolution at a level -- below 10$^{-14}$~m/s$^{2}$/Hz$^{1/2}$ -- that should guarantee most of the science return for an observatory like eLISA. This talk will address the LPF measurement concept, our physical model for the limits of achieving and measuring near perfect free-fall, and the applicability of LPF towards eLISA and future ambitious gravitational measurements in space.

While LISA Pathfinder will demonstrate significant aspects of the optical metrology needed for an eLISA-type gravitational waves mission, there are important additional features that will be required for eLISA. This talk will review the final interferometer delivered for LISA Pathfinder and discuss the ongoing experimental program to address the interferometry extensions needed for eLISA.

Abstract to be submitted