# energy_low(keV)  energy_high(keV)  fractional_rms  fractional_rms_error
     0.300000          0.460000              -NaN              -NaN    
     0.460000          0.700000        0.00688789        0.00551547    
     0.700000           1.00000              -NaN              -NaN    
      1.00000           1.54000              -NaN              -NaN    
      1.54000           2.40000              -NaN              -NaN    
      2.40000           4.80000         0.0265630        0.00758078    
      4.80000           10.0000         0.0242793         0.0142429