DisPro allows the user to process files created by DSP (dispersion) Brewer routine. Each file (spectral scan) is plotted on the screen and processed to find the peak of the spectral line and the optical width of the slit. The user can select or deselect individual scans without renaming the files. The selected scans are then used to calculate the dispersion coefficients which can be saved into a file.

The program suggests which scans do not fit well to the quadratic polynomial. These scans can be looked at and either rejected or kept. The results of the calculation can be saved in a similar format that is used by LINEFIT program, but with more useful information added. Plots of all scans can be printed on a single page for records.

The main advantages of using DisPro are:

• The program correctly processes scans from slit 0. LINEFIT does not take into account that slit 0 is narrower in some instruments and calculates wrong optical width as a result.
  
• All results are easy to see and assess the quality of the data. Sometimes, a noise spike can ruin a scan and this is often hard to notice without actually plotting the scan.
  
• The ability of DisPro to compare previously created dispersion constants to the ones just calculated gives the user a clear picture of what has changed in the dispersion characteristics of the instrument.
  
• The program handles the scan file names differently from LINEFIT and eliminates the limit on the number of spectral lines that can be processed at one time.
  

Here is an example of DisPro output:

918 Wavelength(A) 3021.20 3062.92 3100.52 3135.10 3168.23 3200.26 SO2: 1.1465

     Resolution(A)    8.27   10.48   10.20   10.68   10.40   10.29

     O3 Abs (1/cm)  3.1506  1.7835  1.0053  0.6773  0.3749  0.2929  O3: 0.3400

 Ozone weighting:     0.00    0.00   -1.00   -0.35    3.88   -2.53  O3: 0.5290

 SO2   weighting:     0.00   -1.00    0.00    0.00    4.44   -3.44 SO2: 1.1269

 Rayleigh coeff.:     5409    5097    4835    4609    4405    4219  -2.2 /   -5.8 (DU)

 Rayleigh orign.:        0    4870    4620    4410    4220    4040  +0.6 /   -5.3 (DU)



Umkher:

2402 Wavelength(A) 3123.44 3164.05 3200.38 3233.72 3265.54 3296.35 SO2: 0.2899

     Resolution(A)    8.20   10.24    9.98   10.48   10.06    9.72

log(10)*O3abs       1.6453  0.9022  0.6739  0.2725  0.1144  0.0768  O3: 0.1809

 Ozone weighting:     0.00    0.00   -1.00   -6.99   17.52   -9.53  O3: 1.3065

 SO2   weighting:     0.00   -1.00    0.00    0.00    4.44   -3.44 SO2: 0.2860

 Rayleigh coeff.:     4684    4431    4219    4035    3870    3718



Zero = 2687   CalStep = 920   UmkOffset = 2402  NO2 switch = 2665



For umksetup:

 4.1000   2.3136   1.5578   0.8638

 0.6739   0.2725   0.1144   0.0768

An example of calculation results and a printout of the scans can be downloaded in pdf format.