# energy_low(keV)  energy_high(keV)  fractional_rms  fractional_rms_error
     0.300000          0.460000              -NaN              -NaN    
     0.460000          0.700000              -NaN              -NaN    
     0.700000           1.00000         0.0454579         0.0170590    
      1.00000           1.54000              -NaN              -NaN    
      1.54000           2.40000         0.0348775         0.0478204    
      2.40000           4.80000         0.0451609         0.0503053    
      4.80000           10.0000              -NaN              -NaN