# energy_low(keV)  energy_high(keV)  fractional_rms  fractional_rms_error
     0.300000          0.460000         0.0127282        0.00430590    
     0.460000          0.700000         0.0118995        0.00347517    
     0.700000           1.00000         0.0103278        0.00455300    
      1.00000           1.54000        0.00770672        0.00536413    
      1.54000           2.40000        0.00417559        0.00889860    
      2.40000           4.80000              -NaN              -NaN    
      4.80000           10.0000              -NaN              -NaN