# energy_low(keV)  energy_high(keV)  fractional_rms  fractional_rms_error
     0.300000          0.460000         0.0211548        0.00419915    
     0.460000          0.700000              -NaN              -NaN    
     0.700000           1.00000              -NaN              -NaN    
      1.00000           1.54000              -NaN              -NaN    
      1.54000           2.40000              -NaN              -NaN    
      2.40000           4.80000         0.0170906        0.00575632    
      4.80000           10.0000         0.0366298         0.0106883