Sensor noise in <i>LISA Pathfinder</i>: An extensive in-flight review of the angular and longitudinal interferometric measurement system
M. Armano, H. Audley, J. Baird, Pierre Binétruy, M. Born, D. Bortoluzzi, Nico Brandt, E. Castelli, A. Cavalleri, A. Cesarini, A. M. Cruise, K. Danzmann, M. de Deus Silva, I. Diepholz, George 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, Felipe Guzmán, I. Harrison, M-S Hartig, Gerald Hechenblaikner, Gerhard Heinzel, M. Hewitson, D. Hollington, D. Hoyland, M. Hueller, H. Inchauspé, O. Jennrich, P. Jetzer, Ulrich Johann, B. Johlander, Nikolaos Karnesis, B. Kaune, C. J. Killow, Natalia Korsakova, J. A. Lobo, J. P. López-Zaragoza, R. Maarschalkerweerd, D. Mance, V. Martín, L. Martin-Polo, F. Martín-Porqueras, J. Martino, P. W. McNamara, João Mendes, L. Mendes, N. Meshksar, A. Monsky, M. Nofrarías, S. Paczkowski, M. Perreur-Lloyd, Antoine Petiteau, E. Plagnol, J. Ramos-Castro, J. Reiche, F. Rivas, D. I. Robertson, G. Russano, Jose Sanjuán, J. Slutsky, Carlos F. Sopuerta, Frank Steier, T. J. Sumner, D. Texier, J. I. Thorpe, D. Vetrugno, S. Vitale, Vinzenz Wand, Gudrun Wanner, H. Ward, Peter Wass, W. J. Weber, L. Wissel, A. Wittchen, P. Zweifel
Abstract
In a previous article [1], we have reported on the first subpicometer interferometer flown in space as part of ESA's LISA Pathfinder mission, and have shown the residual sensor noise to be on the level of ${32.0}_{\ensuremath{-}1.7}^{+2.4}\text{ }\text{ }\mathrm{fm}/\sqrt{\mathrm{Hz}}$. This review provides a deeper and more complete overview of the full system and its interferometric mission performance under varying operational conditions, allowing a much more detailed view on the noise model. We also include the optical measurements of rotations through differential wave front sensing (DWS), which reached a sensitivity of as good as $100\text{ }\mathrm{prad}/\sqrt{\mathrm{Hz}}$. We present more evidence for the long-term stability of the interferometric performance and components. This proves a solid foundation for future interferometry in space such as the LISA mission.