# energy_low(keV)  energy_high(keV)  fractional_rms  fractional_rms_error
     0.300000          0.460000              -NaN              -NaN    
     0.460000          0.700000         0.0236219         0.0140881    
     0.700000           1.00000              -NaN              -NaN    
      1.00000           1.54000         0.0341249         0.0104024    
      1.54000           2.40000         0.0436553         0.0137384    
      2.40000           4.80000         0.0158472         0.0245655    
      4.80000           10.0000              -NaN              -NaN