Comment on "rf Wien filter in an electric dipole moment storage ring:   The "partially frozen spin'' effect''
  The Jacobi-Anger identity is employed to quantify the findings of Morse, Orlov and Semertzidis [1]. The secular term in the longitudinal spin component is proportional to a Bessel function. A suggestion for values of machine parameters to optimize the secular term is presented. 
S. R. Mane
physics.acc-ph