High-granularity detector material measurements at test-beams - from concept to exploitation

by Simon Koch (CERN)

Thursday 2 Oct 2025, 11:00 → 12:00 Europe/Zurich

32/1-A24 (CERN)

Precise knowledge of detector material for particle detectors is crucial both during the R&D phase and during operation as an input to simulations, in particular for tracking detectors in which momentum and position resolution are highly sensitive to traversed material. Most past and current projects rely on coarse-grained estimates derived from a nominal design, the accuracy of which can be heavily impacted by difficult-to-estimate components or the physical realities of the final detector construction, often resulting in uncertainties on the detector model exceeding O(10%). Introducing direct radiation length measurements of individual components or larger assemblies as part of the R&D phase for new detectors would assist both in allowing well-informed choices of materials and components, and in substantially reducing final uncertainties on the detector model.

This talk will introduce a mature methodology for measuring material content via the multiple scattering of electrons at testbeams. Participants will be introduced to the purpose-built low-mass MONSTAR telescope, alongside a discussion of design choices and relevant beam requirements. The first direct measurements of several ATLAS ITk Pixel detector components including modules, support structures, and electrical interconnects will be presented, followed by a discussion of the scalability and wider applicability of the methodology.

SK_Seminar_DT_training.pdf