The spatial resolution of the Micromegas prototype developed for the BabyIAXO experiment was evaluated using a low-energy X-ray beam at the SOLEIL synchrotron facility. BabyIAXO, currently under construction, aims to search for hypothetical solar axions. A key component of the experiment is a low-background X-ray detector with high efficiency in the 1-10 keV energy range and stringent background rejection capabilities. Achieving a spatial resolution on the order of, or better than, 1 mm is critical for accurately reconstructing signal shapes and positions, and for effectively discriminating between signal and background events. Therefore, a precise characterization of the detector's spatial resolution is essential to validate its suitability for the experiment. This study involved scanning the IAXO-D1 Micromegas detector under various beam energies, positions, and drift field configurations to evaluate their influence on spatial resolution. A resolution of approximately 100 μm at 6 keV was achieved, confirming the strong potential of this technology for application in the final BabyIAXO setup.
@article{arxiv.2509.08138,
title = {Spatial resolution studies with the BabyIAXO Micromegas prototype},
author = {A. Quintana and J. Castel and S. Cebrián and T. Dafni and D. Díez-Ibáñez and E. Ferrer-Ribas and A. Ezquerro and J. Galán and J. A. García and A. Giganon and C. Goblin and N. Goyal and F. J. Iguaz and I. G Irastorza and C. Loiseau and G. Luzón and C. Margalejo and H. Mirallas and L. Obis and T. Papaevangelou and O. Pérez and J. Porrón and M. J. Puyuelo},
journal= {arXiv preprint arXiv:2509.08138},
year = {2025}
}