TY - JOUR
T1 - The 17 mev anomaly in beryllium decays and u(1) portal to dark matter
AU - Chen, Chian Shu
AU - Lin, Guey Lin
AU - Lin, Yen Hsun
AU - Xu, Fanrong
N1 - Publisher Copyright:
© Copyright owned by the author(s).
PY - 2017
Y1 - 2017
N2 - The experiment of Krasznahorkay et al observed the transition of a 8Be excited state to its ground state and accompanied by an emission of e+e− pair with 17 MeV invariant mass. This 6.8σ anomaly can be fitted by a new light gauge boson. We consider the new particle as a U(1) gauge boson, Z0, which plays as a portal linking dark sector and visible sector. In particular, we study the new U(1) gauge symmetry as a hidden or non-hidden group separately. The generic hidden U(1) model, referred to as dark Z model, is excluded by imposing various experimental constraints. On the other hand, a non-hidden Z0 is allowed due to additional interactions between Z0 and Standard Model fermions. We also study the implication of the dark matter direct search on such a scenario. We found the search for the DM-nucleon scattering cannot probe the parameter space that is allowed by 8Be-anomaly for the range of DM mass above 500 MeV. However, the DM-electron scattering for DM between 20 and 50 MeV can test the underlying U(1) portal model using the future Si and Ge detectors with 5e− threshold charges.
AB - The experiment of Krasznahorkay et al observed the transition of a 8Be excited state to its ground state and accompanied by an emission of e+e− pair with 17 MeV invariant mass. This 6.8σ anomaly can be fitted by a new light gauge boson. We consider the new particle as a U(1) gauge boson, Z0, which plays as a portal linking dark sector and visible sector. In particular, we study the new U(1) gauge symmetry as a hidden or non-hidden group separately. The generic hidden U(1) model, referred to as dark Z model, is excluded by imposing various experimental constraints. On the other hand, a non-hidden Z0 is allowed due to additional interactions between Z0 and Standard Model fermions. We also study the implication of the dark matter direct search on such a scenario. We found the search for the DM-nucleon scattering cannot probe the parameter space that is allowed by 8Be-anomaly for the range of DM mass above 500 MeV. However, the DM-electron scattering for DM between 20 and 50 MeV can test the underlying U(1) portal model using the future Si and Ge detectors with 5e− threshold charges.
UR - http://www.scopus.com/inward/record.url?scp=85051527297&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=85051527297&partnerID=8YFLogxK
M3 - Conference article
AN - SCOPUS:85051527297
SN - 1824-8039
JO - Proceedings of Science
JF - Proceedings of Science
T2 - 2017 European Physical Society Conference on High Energy Physics, EPS-HEP 2017
Y2 - 5 July 2017 through 12 July 2017
ER -