# energy_low(keV)  energy_high(keV)  fractional_rms  fractional_rms_error
     0.300000          0.460000              -NaN              -NaN    
     0.460000          0.700000        0.00960049        0.00817707    
     0.700000           1.00000         0.0208719        0.00717949    
      1.00000           1.54000        0.00537707         0.0115350    
      1.54000           2.40000         0.0179876        0.00929253    
      2.40000           4.80000              -NaN              -NaN    
      4.80000           10.0000         0.0109638         0.0235991