# 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        0.00336445        0.00580333    
      1.00000           1.54000        0.00840228        0.00435001    
      1.54000           2.40000         0.0112099        0.00514579    
      2.40000           4.80000        0.00336684        0.00885326    
      4.80000           10.0000         0.0168438        0.00892475