# 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        0.00732005        0.00783302    
      1.00000           1.54000        0.00989402        0.00692618    
      1.54000           2.40000         0.0207551        0.00589185    
      2.40000           4.80000         0.0203904        0.00833324    
      4.80000           10.0000         0.0184964         0.0133590