Measurements of the ion fraction and mobility of alpha and beta decay products in liquid xenon using the EXO-200 后印本

摘要: Alpha decays in the EXO-200 detector are used to measure the fraction of charged�18Po燼nd�14Bi燿aughters created from alpha and beta decays, respectively.�22Rn燼lpha decays in liquid xenon (LXe) are found to produce218Po+爄ons�0.3�.0%爋f the time, while the remainder of the�18Po燼toms are neutral. The fraction of�14Bi+爁rom�14Pb燽eta decays in LXe is found to be�6.4�.7%, inferred from the relative rates of�18Poand�14Po燼lpha decays in the LXe. The average velocity of�18Po爄ons is observed to decrease for longer drift times. Initially the ions have a mobility of�.390�.006燾m2/(kV爏), and at long drift times the mobility is�.219�.004燾m2/(kV爏). Time constants associated with the change in mobility during drift of the�18Po+爄ons are found to be proportional to the electron lifetime in the LXe.