• Corpus ID: 231749522

A Standard Model Explanation for the"ATOMKI Anomaly"

  title={A Standard Model Explanation for the"ATOMKI Anomaly"},
  author={Aleksandrs Aleksejevs and Svetlana Barkanova and Yu. G. Kolomensky and B. Sheff},
Using the e+e− pair spectrometer at the 5 MV Van de Graaff accelerator at the Institute for Nuclear Research, Hungarian Academy of Sciences (ATOMKI), Krasznahorkay et al. have claimed a 6.8σ excess at high e+e− opening angles in the internal pair creation isoscalar transition Be(18.15) → Be e+e−. A hypothetical gauge boson with the mass circa 17 MeV, “X17”, has been proposed as an explanation for the excess. We show that the observed experimental structure can be reproduced within the Standard… 

Challenges for a QCD axion at the 10 MeV scale

Abstract We report on an interesting realization of the QCD axion, with mass in the range $$ \mathcal{O} $$ O (10) MeV. It has previously been shown that although this scenario is stringently

Investigation of CMB constraints for dark matter-helium scattering

We study dark matter-helium scattering in the early Universe and its impact on constraints from cosmic microwave background (CMB) anisotropy measurements. We describe possible theoretical frameworks

MEG II experiment status and prospect

  • M. Meucci
  • Physics
    Proceedings of The 22nd International Workshop on Neutrinos from Accelerators — PoS(NuFact2021)
  • 2022
The MEG II experiment at Paul Scherrer Institute (PSI) in Switzerland aims to achieve a sensitivity of 6 × 10−14 on the charged lepton flavor violating decay μ+ → e+γ. The current upper limit on this

Towards a New μ→eγ Search with the MEG II Experiment: From Design to Commissioning

The MEG experiment represents the state of the art in the search for the Charged Lepton Flavour Violating μ+→e+γ decay. With its first phase of operations at the Paul Scherrer Institut (PSI), MEG set

The X 17 boson and the

M. Viviani, E. Filandri, L. Girlanda, C. Gustavino, A. Kievsky, L.E. Marcucci, and R. Schiavilla INFN-Pisa, I-56127, Pisa, Italy University of Trento, 38123 Trento, Italy INFN-TIFPA, 38123




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