# energy_low(keV)  energy_high(keV)  fractional_rms  fractional_rms_error
     0.300000          0.460000         0.0108973        0.00257262    
     0.460000          0.700000              -NaN              -NaN    
     0.700000           1.00000        0.00869531        0.00310117    
      1.00000           1.54000              -NaN              -NaN    
      1.54000           2.40000        0.00677213        0.00482392    
      2.40000           4.80000         0.0134292        0.00490189    
      4.80000           10.0000        0.00968229        0.00965653