Investigating correlations in time delay interferometry combinations of LISA data

摘要: The detection of Gravitational Waves using the Laser Interferometer Space Antenna (LISA) will open whole new areas physics and astrophysics for exploration. lower frequency signals detected by antenna allow us to probe gravitational wave sources that are inaccessible with current future ground based detectors. However, ability LISA detect is dependent on removal laser noise realisations from optical bench measurements, would otherwise dominate signal data streams. Time Delay Interferometry (TDI) provides a method removing contributions time shifting individual measurements. cancellation achieved identifying measurements contain equal numbers identical but opposing signs. Although TDI combinations produce datastreams free contributions, means combination streams defined at different stamps nevertheless remaining detector terms. Independent (denoted A, E T) can be constructed simpler laser-noise cancelling diagonalising correlation matrix any given timestamp. This ensures optimal independent respect each other this particular timestamp, result does not apply when compared timestamps. As introduces within them identically terms, T could therefore correlated in time. The presence, potential impact, these correlations has been investigated first thesis. work carried out designations terms algebraic expression combination. resultant configuration non-zero off-diagonal covariance simplified models constellation. The presence between pose serious problem number parameter search methods rely being independent. The effects recovery containing two sinusoids model produced second Mock Data Challenge. In both cases, auto cross combinations. When covariances were explicitly accounted likelihood function, confidence intervals, reflecting uncertainty our inference unknown parameters, found significantly smaller - indicating tighter constraints true comparison results obtained function assumed time.