In this paper, we describe the procedure implemented in the Multi-Band Template Analysis (MBTA) search pipeline to produce online posterior distributions of compact binary coalescence (CBC) gravitational-wave parameters. This procedure relies on an SNR optimizer technique, which consists of filtering dense local template banks. We present how these banks are constructed using information from the initial detection and detail how the results of the filtering are used to estimate source parameters and provide posterior distributions. We demonstrate the performance of our procedure on simulations and compare our source parameter estimates with the results from the first part of the fourth observing run (O4a) recently released by the LIGO-Virgo-KAGRA (LVK) collaboration.
@article{arxiv.2601.20512,
title = {Enhancing online estimation of CBC parameters with the low-latency MBTA analysis},
author = {Florian Aubin and Inès Bentara and Damir Buskulic and Gianluca M Guidi and Vincent Juste and Morgan Lethuillier and Frédérique Marion and Lorenzo Mobilia and Benoît Mours and Amazigh Ouzriat and Thomas Sainrat and Viola Sordini},
journal= {arXiv preprint arXiv:2601.20512},
year = {2026}
}