> I'm not saying it's not possible, it's just extremely unlikely.
Which is more unlikely though, that the FPGA has an issue where precision can be worse than 60ns, or that we're wrong about the speed of light / the ability of matter to travel beyond that speed? We're talking about hard to believe things here, so we shouldn't discard the possibility that this was the failure point simply because it's unbelievable.
I know you're not discarding the idea, and I welcome the context you bring to the discussion; I just wanted to point out that in this case there really isn't much that should be thrown out as impossible.
A systematic uncertainy is very possible, but a systematic uncertainty is a combination of things.
Assuming it's on the FPGA/DAQ side first and foremost is silly because there's multiple systems involved and they are geographically very far apart. Maybe someone forgot that they cut the cables shorter somewhere, or someone is using different cable with a different velocity factor than they are used to. Maybe their geometries are off by 18 meters.
The experimental setup and calibration, along with how it is performed, is much more important than any single component. Assuming it's the (seemingly) most complicated piece in the experiment is wrong. Everything needs to be checked and double checked at this point.
Which is more unlikely though, that the FPGA has an issue where precision can be worse than 60ns, or that we're wrong about the speed of light / the ability of matter to travel beyond that speed? We're talking about hard to believe things here, so we shouldn't discard the possibility that this was the failure point simply because it's unbelievable.
I know you're not discarding the idea, and I welcome the context you bring to the discussion; I just wanted to point out that in this case there really isn't much that should be thrown out as impossible.