The International AXion Observatory (IAXO) is a large scale axion helioscope
that will look for axions and axion-like particles produced in the Sun with
unprecedented sensitivity. BabyIAXO is an intermediate experimental stage that
will be hosted at DESY (Germany) and that will test all IAXO subsystems serving
as a prototype for IAXO but at the same time as a fully-fledged helioscope with
potential for discovery.
One of the crucial components of the project is the ultra-low background
X-ray detectors that will image the X-ray photons produced by axion conversion
in the experiment. The baseline detection technology for this purpose are
Micromegas (Microbulk) detectors. We will show the quest and the strategy to
attain the very challenging levels of background targeted for BabyIAXO that
need a multi-approach strategy coming from ground measurements, screening
campaigns of components of the detector, underground measurements, background
models, in-situ background measurements as well as powerful rejection
algorithms. First results from the commissioning of the BabyIAXO prototype will
be shown.Comment: 4 pages, 2 figures, submitted for the proceedings of the
International Conference on Micro Pattern Gaseous Detectors, December 2022,
Israe