# energy_low(keV)  energy_high(keV)  fractional_rms  fractional_rms_error
     0.300000          0.460000              -NaN              -NaN    
     0.460000          0.700000         0.0100048        0.00700028    
     0.700000           1.00000              -NaN              -NaN    
      1.00000           1.54000         0.0291091         0.0112156    
      1.54000           2.40000              -NaN              -NaN    
      2.40000           4.80000         0.0202702        0.00538451    
      4.80000           10.0000        0.00301376        0.00598946