# energy_low(keV)  energy_high(keV)  fractional_rms  fractional_rms_error
     0.300000          0.460000              -NaN              -NaN    
     0.460000          0.700000         0.0298794         0.0149846    
     0.700000           1.00000         0.0150016         0.0217425    
      1.00000           1.54000         0.0168049         0.0168125    
      1.54000           2.40000         0.0257417         0.0138041    
      2.40000           4.80000         0.0309904         0.0191454    
      4.80000           10.0000              -NaN              -NaN