TY - JOUR

T1 - Influence of Laser Relative-Intensity Noise on the Laser Interferometer Space Antenna

AU - Wissel, L.

AU - Hartwig, O.

AU - Bayle, J. B.

AU - Staab, M.

AU - Fitzsimons, E. D.

AU - Hewitson, M.

AU - Heinzel, G.

N1 - Funding Information: The authors would like to thank M. Misfeldt for his insightful comment. The Albert Einstein Institute gratefully acknowledges the support of the German Space Agency, DLR. The work is supported by the Federal Ministry for Economic Affairs and Energy based on a resolution of the German Bundestag (Grants No. FKZ 50OQ0501, No. FKZ 50OQ1601, and No. FKZ 50OQ1801). J.B. gratefully acknowledges support from the UK Space Agency via STFC (ST/W002825/1). O.H. gratefully acknowledges support from the Centre National d’Études Spatiales (CNES) and the Programme National GRAM of CNRS/INSU with INP and IN2P3 cofunded by CNES.

PY - 2023/7/10

Y1 - 2023/7/10

N2 - The Laser Interferometer Space Antenna (LISA) is an upcoming European Space Agency mission that will detect gravitational waves in space by interferometrically measuring the separation between free-falling test masses at picometer precision. To reach the desired performance, LISA will employ the noise reduction technique time-delay interferometry (TDI), in which multiple raw interferometric readouts are time shifted and combined into the final scientific observables. Evaluating the performance in terms of these TDI variables requires careful tracking of how different noise sources propagate through TDI, as noise correlations might affect the performance in unexpected ways. One example of such potentially correlated noise is the relative-intensity noise (RIN) of the six lasers aboard the three LISA satellites, which will couple into the interferometric phase measurements. In this article, we calculate the expected RIN levels based on the current mission architecture and the envisaged mitigation strategies. We find that strict requirements on the technical design reduce the effect from approximately 8.7pm/Hz per interspacecraft interferometer to that of a much lower sub-1-pm/Hz noise, with typical characteristics of an uncorrelated readout noise after TDI. Our investigations underline the importance of sufficient balanced detection of the interferometric measurements.

AB - The Laser Interferometer Space Antenna (LISA) is an upcoming European Space Agency mission that will detect gravitational waves in space by interferometrically measuring the separation between free-falling test masses at picometer precision. To reach the desired performance, LISA will employ the noise reduction technique time-delay interferometry (TDI), in which multiple raw interferometric readouts are time shifted and combined into the final scientific observables. Evaluating the performance in terms of these TDI variables requires careful tracking of how different noise sources propagate through TDI, as noise correlations might affect the performance in unexpected ways. One example of such potentially correlated noise is the relative-intensity noise (RIN) of the six lasers aboard the three LISA satellites, which will couple into the interferometric phase measurements. In this article, we calculate the expected RIN levels based on the current mission architecture and the envisaged mitigation strategies. We find that strict requirements on the technical design reduce the effect from approximately 8.7pm/Hz per interspacecraft interferometer to that of a much lower sub-1-pm/Hz noise, with typical characteristics of an uncorrelated readout noise after TDI. Our investigations underline the importance of sufficient balanced detection of the interferometric measurements.

UR - http://www.scopus.com/inward/record.url?scp=85165000010&partnerID=8YFLogxK

U2 - 10.48550/arXiv.2212.12052

DO - 10.48550/arXiv.2212.12052

M3 - Article

AN - SCOPUS:85165000010

VL - 20

JO - Physical review applied

JF - Physical review applied

SN - 2331-7019

IS - 1

M1 - 014016

ER -