# energy_low(keV)  energy_high(keV)  fractional_rms  fractional_rms_error
     0.300000          0.460000         0.0449517         0.0173656    
     0.460000          0.700000              -NaN              -NaN    
     0.700000           1.00000         0.0214688         0.0118992    
      1.00000           1.54000              -NaN              -NaN    
      1.54000           2.40000         0.0430049         0.0257704    
      2.40000           4.80000         0.0780563         0.0304428    
      4.80000           10.0000         0.0831990         0.0183162