# Arm locking performance with the new LISA design

**Authors:** Sourath Ghosh, Josep Sanjuan, Guido Mueller  
**arXiv:** [2112.00837](https://arxiv.org/abs/2112.00837)  
**Date:** 2021-12-01  
**Summary page:** https://www.summarizepaper.com/en/arxiv-id/2112.00837v1/

## Key points

- The Laser Interferometer Space Antenna (LISA) is a space-based gravitational wave detector designed for low frequency range of 0.1 mHz to 1 Hz.
- Interferometer signals of LISA are affected by laser frequency noise, requiring reduction by approximately 7 orders of magnitude using Time-Delay Interferometry (TDI).
- Arm locking has been proposed as a solution to decrease laser frequency noise by several orders of magnitude and mitigate risks associated with TDI.
- A recent study by Sourath Ghosh, Josep Sanjuan, and Guido Mueller presented an updated performance model for arm locking in the new LISA mission.
- The model considered factors such as 2.5 Gm arm lengths, clock noise assumptions, spacecraft motion based on data from LISA Pathfinder, and shot noise considerations.
- The study also included updates on Doppler frequency pulling estimates during lock acquisition.
- Arm locking is crucial for enhancing LISA's gravitational wave detection capabilities and improving sensitivity and accuracy in capturing elusive gravitational wave signals from distant cosmic events.
- This research contributes valuable insights to the ongoing development and optimization efforts for future space-based gravitational wave detectors like LISA.

## Summary

The Laser Interferometer Space Antenna (LISA) is a cutting-edge space-based gravitational wave detector designed to detect sources emitting in the low frequency range of 0.1 mHz to 1 Hz. The interferometer signals of LISA are primarily affected by laser frequency noise and require reduction by approximately 7 orders of magnitude using Time-Delay Interferometry (TDI). To mitigate potential risks associated with TDI, arm locking has been proposed as a solution to decrease laser frequency noise by several orders of magnitude. In a recent study conducted by Sourath Ghosh, Josep Sanjuan, and Guido Mueller from the Department of Physics at the University Of Florida, an updated performance model for arm locking in the new LISA mission was presented. This model incorporated various factors such as 2.5 Gm arm lengths, clock noise assumptions, spacecraft motion based on data from LISA Pathfinder, and shot noise considerations. Additionally, the study included updates on Doppler frequency pulling estimates during lock acquisition. The research sheds light on the importance of arm locking in enhancing the performance of LISA's gravitational wave detection capabilities. By refining and optimizing this aspect of the mission design, researchers aim to improve the overall sensitivity and accuracy of LISA in capturing elusive gravitational wave signals from distant cosmic events. This work contributes valuable insights to the ongoing development and optimization efforts for future space-based gravitational wave detectors like LISA.