# energy_low(keV)  energy_high(keV)  fractional_rms  fractional_rms_error
     0.300000           1.00000         0.0294734        0.00578563    
      1.00000           2.00000        0.00695771         0.0160259    
      2.00000           10.0000         0.0288055         0.0142769