doi:10.1016/j.nima.2025.171176engQuintana, A.Castel, J.Cebrián, S.Dafni, T.Díez-Ibáñez, D.Ferrer-Ribas, E.Ezquerro, A.Galán, J.García, J.A.Giganon, A.Goblin, C.Goyal, N.Iguaz, F.J.García Irastorza, I.Loiseau, C.Luzón, G.Margalejo, C.Mirallas, H.Obis, L.Papaevangelou, T.Pérez, O.Porrón, J.Jiménez Puyuelo, M.Spatial resolution studies with the BabyIAXO Micromegas prototypeART-2025-146410The 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.2025http://zaguan.unizar.es/record/16421010.1016/j.nima.2025.171176http://zaguan.unizar.es/record/164210oai:zaguan.unizar.es:164210info:eu-repo/grantAgreement/EC/H2020/788781/EU/Towards the detection of the axion with the International Axion Observatory/IAXOplusThis project has received funding from the European Union’s Horizon 2020 research and innovation program under grant agreement No H2020 788781-IAXOplusinfo:eu-repo/grantAgreement/ES/MICINN/PID2022-137268NB-C51Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment 1083 (2025), 171176 [8 pp.]byhttps://creativecommons.org/licenses/by/4.0/deed.esinfo:eu-repo/semantics/openAccess