Function: FWHM of a emission lines array for a list of 2D images Syntax: int_fwhm A_file P_file dispaxis nx ny outfile Parameters:
Description: Firstly, you must to have opened a graphics display (e.g. Saoimage).
With this task we obtain for a list of arc images the FWHM (from a gaussian fit) for several emission features. For each one of the arc image, a mean value of the FWHM and the standard desviation is obtained from the different FWHM values. The A_file file contains two columns (focus, arc image) in each row:
| -3000.0 | I1.imh |
| -2000.0 | I2.imh |
| -1000.0 | I3.imh |
| 0.0 | I4.imh |
| 1000.0 | I5.imh |
| 2000.0 | I6.imh |
| 3000.0 | I7.imh |
We have to select features as isolated as possible in order obtain the centers (with the imcntr task) of these ones with a good precision (around a 1 pixel). P_file is a input file of two columns containing the approximate (around 1 pixel) coordinates X and Y of the emission features, which are distributed over all detector. An example of P_file:
| 20 | 20 |
| 520 | 25 |
| 1002 | 22 |
| 23 | 527 |
| 542 | 532 |
| 985 | 520 |
| 24 | 1003 |
| 541 | 1012 |
| 1003 | 1007 |
The dispaxis parameter (0: horizontal axis, 1: vertical axis) corresponds to the dispersion axis on the CCD.
The outfile is the file with the different output files names. These outfiles contain the FWHM values of the gaussian fits for the different emission features whose coordinates are in P_file. On graphics display, int_fwhm shows the selected emission features: these emission features are marked with tvmark. And the values corresponding to the centers of the emission lines are determined from gaussian fits done with imexamine. Likewise, int_fwhm show the fits with gkimosaic task. A mean value of the FWHM and the standard desviation for each one of the arc image is showed too.