# energy_low(keV)  energy_high(keV)  fractional_rms  fractional_rms_error
     0.300000          0.460000         0.0301940         0.0136985    
     0.460000          0.700000         0.0294044         0.0143372    
     0.700000           1.00000         0.0440736         0.0163164    
      1.00000           1.54000         0.0529083         0.0189211    
      1.54000           2.40000              -NaN              -NaN    
      2.40000           4.80000              -NaN              -NaN    
      4.80000           10.0000        0.00169331         0.0127975