# energy_low(keV)  energy_high(keV)  fractional_rms  fractional_rms_error
     0.300000          0.460000         0.0157179        0.00847867    
     0.460000          0.700000         0.0217572        0.00680707    
     0.700000           1.00000              -NaN              -NaN    
      1.00000           1.54000         0.0234807         0.0108084    
      1.54000           2.40000              -NaN              -NaN    
      2.40000           4.80000         0.0410372        0.00632833    
      4.80000           10.0000         0.0586192        0.00426338