# energy_low(keV)  energy_high(keV)  fractional_rms  fractional_rms_error
     0.300000          0.460000              -NaN              -NaN    
     0.460000          0.700000              -NaN              -NaN    
     0.700000           1.00000         0.0564472         0.0803685    
      1.00000           1.54000              -NaN              -NaN    
      1.54000           2.40000          0.100779         0.0169853    
      2.40000           4.80000         0.0929082         0.0125941    
      4.80000           10.0000         0.0489519         0.0220507