Particle physics today faces the challenge of explaining the mystery of dark matter, the origin
of matter over anti-matter in the Universe, the origin of the neutrino masses, the apparent …

The workshop “Shedding light on X17” brings together scientists looking for the existence of
a possible new light particle, often referred to as X17. This hypothetical particle can explain …

Resonant positron annihilation on atomic electrons provides a powerful method to search for
light new particles coupled to e+ e-. Reliable estimates of production rates require a detailed …

The standard model (SM) of particle physics is the mathematical description of the
fundamental constituents and interactions of matter. Its last missing particle, the Higgs …

A bstract In view of the latest experimental results recently released by the ATOMKI
collaboration, we critically re-examine the possible theoretical interpretation of the observed …

Recent data from the ATOMKI group continue to confirm their claim of the existence of a
new∼ 17 MeV particle. We review and numerically analyze the data and then put into …

Observations of anomalies in the electron-positron angular correlations in high-energy
decays in He 4, Be 8, and C 12 have been reported recently by the ATOMKI collaboration …

A bstract We revisit the gauged U (1) B− L explanation of the ATOMKI nuclear anomalies, in
which the new gauge boson is the hypothetical X (17) particle. It is known that the vanilla B …