erek
[H]F Junkie
- Joined
- Dec 19, 2005
- Messages
- 10,898
New evidence supporting the existence of the hypothetic X17 particle
We observed electron-positron pairs from the electro-magnetically forbidden M0 transition depopulating the 21.01 MeV 0− state in 4He. A peak was observed in their e+e− angular correlations at 115∘ with 7.2σ significance, and could be described by assuming the creation and subsequent decay of a light particle with mass of mXc2=16.84±0.16(stat)±0.20(syst) MeV and ΓX= 3.9×10−5 eV. According to the mass, it is likely the same X17 particle, which we recently suggested [Phys. Rev. Lett. 116, 052501 (2016)] for describing the anomaly observed in 8Be.
https://www.independent.co.uk/news/...i-nuclear-research-force-nature-a9210741.html
We observed electron-positron pairs from the electro-magnetically forbidden M0 transition depopulating the 21.01 MeV 0− state in 4He. A peak was observed in their e+e− angular correlations at 115∘ with 7.2σ significance, and could be described by assuming the creation and subsequent decay of a light particle with mass of mXc2=16.84±0.16(stat)±0.20(syst) MeV and ΓX= 3.9×10−5 eV. According to the mass, it is likely the same X17 particle, which we recently suggested [Phys. Rev. Lett. 116, 052501 (2016)] for describing the anomaly observed in 8Be.
https://www.independent.co.uk/news/...i-nuclear-research-force-nature-a9210741.html