# energy_low(keV)  energy_high(keV)  fractional_rms  fractional_rms_error
     0.300000           1.00000        0.00686110        0.00267438    
      1.00000           2.00000         0.0145381        0.00355049    
      2.00000           10.0000         0.0141347        0.00502211