Laboratory characterization of Hierarchical Fringe Tracking

Le résumé fourni par la source

One of the main limitations in long-baseline interferometry lies in its fringe tracking sensitivity. The challenge is therefore to maximize this sensitivity while minimizing the spreading of the signal on the detector. This is the goal at the core of the hierarchical fringe tracking (HFT) concept. We present the laboratory characterization of the 2nd generation HFT chips operating in the near infrared (J and H bands) for up to 6 telescopes with more linear phase and group delay estimators, allowing a strong simplification of the tracking algorithm. We show direct comparison of the limiting sensitivity of fringe sensing between 6-telescopes HFT and ABCD pairwise chips and demonstrate that the new HFT architecture provides a minimum (#telescopes-1) gain independently of the number of apertures. Ultimately, this new chip is intended for implementation on the VLTI, CHARA or on the future Xuyi 100m-baseline Stellar Interferometer using three telescopes.

Ce résumé expose les affirmations des auteurs. BNTIC ne l’interprète pas comme une validation indépendante des résultats.