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Currently external trigger io groups are not propagated through to the end file, this is necessary to apply a clock correction.

@soleti I think it would be really nice to link the zoom range of the projection plots to the 3D viewer, so we can look closely at regions in full 3D. I think it's not super easy to do, but it would certainly be nice.

Something to put on the list, but not an immediate concern.

In module 0, each PACMAN has its own free-running clock that is periodically synchronized with a PPS signal. @mastbaum showed that the two clocks run with slightly (~20-30e-7) different frequencies. This introduces an offset of up to ~mm in the reconstructed drift coordinate, if you use the basic hit timestamps. There are two (or probably more) ways to correct for this:

• instead of using a single, global clock frequency for the two PACMAN, use the measured frequencies relative to the PPS signal and reconstruct drift times / etc independently for each PACMAN based on those
• instead of always using the first external trigger for the t0 in track fitting, use only the trigger generated by each PACMAN to reconstruct the drift time for hits orgininating on the given PACMAN

Both are equally viable options, and probably both should be implemented.

It would be very useful to have the unix_ts in other datasets as well (in particular the ext_trigs dataset) to better allow for charge/light association