# Will no evidence for a new light (17 MeV) particle be independently published before 2021?

In Janurary 2016 Physical Review Letters published a paper by a Hungarian research group reporting anomalous results in the decays of excited beryllium-8 atoms. A careful analysis posted in an April 2016 paper suggests that this anomaly is consistent with the existence of a hitherto unknown light (17 MeV) vector boson.

Since then, interest in this potential new physics has grown, though it is tempered by concern about the experimental group and its previous work; see this story for a nice summary.

As discussed in this story, several ongoing or proposed experiments may be able to independently test the possibility of a new vector boson in this mass range in the next year or two, and it is possible that another team could independently reproduce the original nuclear physics experiment.

A previous question by our glorious leader Anthony resolved on Jan 9, 2018 with no new evidence on the matter. Theoretical work has continued on the subject since (see google scholar) and in October 2019, the original Hungarian group uploaded a new paper to the arxiv where they report observing similar anomalous decays of excited $^4$He atoms.

Question: By beginning of 2021, will no independent group publish or post to the arxiv a paper adducing additional experimental evidence for a new vector boson in the mass range of 10-50 MeV?

By independent, we mean that the paper will not share authors with either the PRL experimental paper or the Feng et al. theoretical paper; by "adduce experimental evidence" we will include both new experiments providing evidence at > 3-sigma or equivalent, or a new theoretical analysis of data other than that of the Hungarian group providing at least 4-sigma or equivalent evidence.

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