Spatial resolution studies with the BabyIAXO Micromegas prototype

A. Quintana; J. Castel; S. Cebrián; T. Dafni; D. Díez-Ibáñez; E. Ferrer-Ribas; A. Ezquerro; J. Galán; J. A. García; A. Giganon; C. Goblin; N. Goyal; F. J. Iguaz; I. G Irastorza; C. Loiseau; G. Luzón; C. Margalejo; H. Mirallas; L. Obis; T. Papaevangelou; O. Pérez; J. Porrón; M. J. Puyuelo

arXiv · 2509.08138

Spatial resolution studies with the BabyIAXO Micromegas prototype

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Abstract

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 $\mu$m at 6 keV was achieved, confirming the strong potential of this technology for application in the final BabyIAXO setup.

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A. Quintana, J. Castel, S. Cebrián, T. Dafni, D. Díez-Ibáñez, E. Ferrer-Ribas, A. Ezquerro, J. Galán, J. A. García, A. Giganon, C. Goblin, N. Goyal, F. J. Iguaz, I. G Irastorza, C. Loiseau, G. Luzón, C. Margalejo, H. Mirallas, L. Obis, T. Papaevangelou, O. Pérez, J. Porrón, M. J. Puyuelo. 2025-09-09. Spatial resolution studies with the BabyIAXO Micromegas prototype. https://arxiv.org/abs/2509.08138

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