# energy_low(keV)  energy_high(keV)  fractional_rms  fractional_rms_error
     0.300000          0.460000         0.0298851         0.0320313    
     0.460000          0.700000         0.0323858         0.0266987    
     0.700000           1.00000         0.0725706         0.0234169    
      1.00000           1.54000              -NaN              -NaN    
      1.54000           2.40000              -NaN              -NaN    
      2.40000           4.80000              -NaN              -NaN    
      4.80000           10.0000         0.0174596         0.0146097