# energy_low(keV)  energy_high(keV)  fractional_rms  fractional_rms_error
     0.300000          0.460000         0.0355518         0.0309401    
     0.460000          0.700000              -NaN              -NaN    
     0.700000           1.00000         0.0299455         0.0476887    
      1.00000           1.54000         0.0741079         0.0242157    
      1.54000           2.40000              -NaN              -NaN    
      2.40000           4.80000         0.0344741         0.0188294    
      4.80000           10.0000         0.0573002         0.0175985