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tehwalrus | 7 years ago

Interesting, but almost certainly a systematic error. We have a lot of experiments over the last few decades detecting neutrinos, and only 2 detecting "sterile" ones (i.e. slightly too many) seems like the outlier.

(These experiments are usually buried underground or similarly crazy in their location, so if they got something wrong about the setup/geology, e.g. If the rocks are slightly radioactive, that could skew the results like this in exactly this way.)

discuss

order

twtw|7 years ago

It's definitely possible, but I just want to point out for other readers that it's not like the collaborators haven't thought about this stuff. Quoting from the article at https://arxiv.org/abs/1805.12028

> Nuclear effects associated with neutrino interactions on carbon can affect the reconstruction of the neutrino energy, E QE , and the determination of the neutrino oscillation parameters [33]. These effects were studied previously [3] and were found to not affect substantially the oscillation fit.

> All of the major backgrounds are constrained by in-situ event measurements, so non-oscillation explanations would need to invoke new anomalous background processes.

Additionally,

> The MiniBooNE excess of events in both oscillation probability and L/E spectrum is, therefore, consistent with the LSND excess of events, even though the two experiments have completely dif- ferent neutrino energies, neutrino fluxes, reconstruction, backgrounds, and systematic uncertainties.

The two "outlier" experiments are consistent with one another. While they might in fact have the same systematic error, that would be quite a coincidence.

imglorp|7 years ago

4.5 sigma is not an outlier. It might still be system error of course.

ncallaway|7 years ago

I think they were saying the experiments themselves were outliers, rather than the data within them.