Toback Group and Rogachev Group collaborated to attempt to replicate 8Be abnormal decay in the Cyclotron Institute at Texas A&M University. This first set of the experiment was conducted in the summer of 2018 and following ones were canceled due to Covid-19. The analysis started thereafter and ended in the summer of 2020.
Besides gamma decay and electron-positron decay, 8Be was found to have another tiny decay branch in which an unknown boson particle was first emitted and then decays to electron-positron pair. This boson particle might be a candidate for dark matter, so named as ‘dark boson’. A detector array, four sets of double sided silicon detector and CsI crystal detector covering 4 walls around the target, was set for particle identification and energy measurements. The electron-positron decayed from the dark boson has a 180° correlation which could be seen by the detector array. Though we didn’t find the boson particle events due to the beam quality and low statistics, we verified the detector system and developed the analysis method.