# energy_low(keV)  energy_high(keV)  fractional_rms  fractional_rms_error
     0.300000          0.460000        0.00420379        0.00354604    
     0.460000          0.700000              -NaN              -NaN    
     0.700000           1.00000              -NaN              -NaN    
      1.00000           1.54000        0.00852120        0.00316702    
      1.54000           2.40000        0.00584925        0.00358806    
      2.40000           4.80000        0.00499260        0.00460137    
      4.80000           10.0000              -NaN              -NaN