摘要
The féeton is the gauge boson of the U(1)_(B−L) gauge theory.If the gauge coupling constant is extremely small,the féeton becomes a candidate for dark matter.We show that its decay to a pair of an electron and a positron explains the observed Galactic 511-keV gamma-ray excess in a consistent manner.This féeton dark matter decays mainly into pairs neutrino and anti-neutrino.Future low-energy experiments with improved directional capability will enable capturing these neutrino signals.The seesaw-motivated parameter space predicts a relatively short féeton lifetime that is comparable to the current cosmological constraint.
基金
Supported by the Talent Scientific Start-Up Project of China
the Natural Science Foundation of China(12175134,12375101,12090060,12090064,12247141)
the SJTU Double First Class start-up fund(WF220442604)
the World Premier International Research Center Initiative(WPI Initiative),MEXT,Japan。
