Beam halo study on ATF damping ring
  Halo distribution is a key topic for background study. This paper has developed an analytical method to give an estimation of ATF beam halo distribution. The equilibrium particle distribution of the beam tail in the ATF damping ring is calculated analytically with different emittance and different vacuum degree. The analytical results agree the measurements very well. This is a general method which can be applied to any electron rings. 
Dou Wang, Philip Bambade, Kaoru Yokoya, Takashi Naito, Jie Gao
physics.acc-ph