Do single-sensor and shared excess events have different origins?
In plain words
When two sensors are mounted on the same crystal, some excess events show up in only one sensor and others in both. Deciding whether these come from the sensor or from the crystal narrows the cause.
Precise statement
In two-channel athermal phonon detectors, excess events split into 'singles' (energy in one sensor only) and 'shared' events (energy in both, absorber-like). The question is whether singles originate in the sensor films (e.g., stress in the superconducting film, quasiparticle bursts) and shared events in the absorber or its mounting, and what fraction of each survives in a stress-free, glue-free mount.
What would settle it
Multi-sensor detectors with varied film thickness, film material and mounting, measuring the singles and shared rates and their time dependence separately.
Status in the literature
Unverified note
Anthony-Petersen et al. (Nature Commun. 2024) linked a large part of the shared-event excess in a two-channel Si detector to holder-induced stress; the source of singles and of the remaining shared events is not settled.