Detecting the gravitational wave memory effect with TianQin

TL;DR

This study evaluates TianQin's potential to detect the gravitational wave memory effect, finding a small but notable chance to observe displacement memory, while spin memory detection remains unlikely.

Contribution

It provides the first detailed analysis of TianQin's capability to detect gravitational wave memory effects, highlighting the conditions under which detection is feasible.

Findings

Approximately 0.5 to 2 signals may have SNR > 3 for displacement memory detection.

Detection of spin memory with TianQin is considered negligible.

Memory effects are significant in specific parameter spaces for waveform modeling.

Abstract

The gravitational wave memory effect is a prediction of general relativity. The presence of memory effect in gravitational wave signals not only provides the chance to test an important aspect of general relativity, but also represents a potentially non-negligible contribution to the waveform for certain gravitational wave events. In this paper, we study the prospect of detecting the gravitational wave memory effect directly with the planned space-based gravitational wave detector -- TianQin. We find that during its 5 years operation, for the gravitational wave signals that could be detected by TianQin, about $0.5\sim2.0$ signals may contain displacement memory effect with signal-to-noise ratios (SNRs) greater than 3. This suggests that the chance for TianQin to detect the displacement memory effect directly is low but not fully negligible. In contrast, the chance to detect the spin memory is negligible. We also study that in which parameter space, the memory effect is expected to be significant in waveform modeling.