Avoiding the uncertainty from correlation between |Delta m_{31}^2| and   CP phase delta in nu_mu --> nu_mu long baseline experiments
  We introduce a new index I_{Delta m_{31}^2} to find where is the better setup of the baseline length and energy to avoid as well as possible the uncertainty from the correlation between Delta m_{31}^2 and cos(delta) in nu_mu --> nu_mu long baseline experiments. 
Keiichi Kimura, Akira Takamura, Tadashi Yoshikawa