Q:  What is the value of N  using the 3302 line?

                                              3302
           log N  =  13.77  -  log( 0.0214 * ------ ) 
                                              5000


                  =  15.62


             -->  N  =  4.2  x  10^(15)  atoms / cm^2



   Q:  What is the value of N  using the 5589 line?

                                              5589
           log N  =  14.91  -  log( 0.645  * ------ ) 
                                              5000


                  =  15.03


             -->  N  =  1.07 x  10^(15)  atoms / cm^2