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The program mosplate is used to define the layout of the MOS mask, and is running under IDL. In addition to displaying the loaded template image, it can also calculate and display the layout of the spectra on the CCD, given the specified aperture layout. New apertures may either be added individually with the cursor or read from a simple ASCII file.
The mosplate program is fully controlled via a graphical user interface and is largely self explanatory. The user interface allows the user to control and adjust all relevant parameters for each slit. A few things are worth mentioning here. The program can be in two states, one state where no aperture is selected and another where an aperture is selected. When no aperture is selected, a click with the mouse in the un-zoomed image creates a new aperture. The positioning of the new aperture can be selected by the user to be either centroid of nearest point source or cursor. However, if there is an existing aperture within 5 arcsec of the cursor position and the positioning mode is centroid, this aperture will be (re)selected rather than defining a new aperture. This allows the user to modify apertures previously defined. When a new aperture is defined, the state changes to aperture selected mode. In this mode, the complete definition of the selected aperture is displayed in the text area near the upper right corner of the mosplate window. The user may now move, resize or delete this aperture. To return to the no aperture selected mode, press the cursor in the un-zoomed image, or if desired, delete the selected aperture.
# Template input file for mosplate # # The file must comply with the following rules: # # The first up to 100 lines may be a header with comments. # Each comment line must contain at least one `#' character. # All lines preceding the header defines the center of a slit (no empty lines!). # Each slit definition line must give the number, X and Y center of a slit. # Number, X and Y goes in first three white space separated columns. # Only digits, decimal comma and white spaces are accepted. # Additional data colums with (numerical) user relevant information are allowed. # # It is desirable but not required that users document the input file # with a header, giving the date of writing, target, template image, # content of columns etc. # # FIELD: M13 # WRITTEN: 99.07.08 # AUTHOR: Michael I. Andersen # TEMPLATE: if230115 # # ID XCEN YCEN MAG 1 90.52 848.96 15.83 2 164.28 872.68 16.11 3 494.23 783.02 18.91 4 538.42 961.27 17.44 5 625.91 1018.23 13.47 6 931.18 913.91 19.02 7 960.01 945.87 17.82 8 1031.62 937.19 17.10 9 1490.46 636.65 18.01 10 1953.57 1024.74 15.33 11 1906.53 1079.42 16.01 12 228.98 868.92 16.90 13 996.74 810.48 17.48 14 1632.23 878.82 17.40 15 2027.20 741.66 18.12 16 1794.68 731.65 18.01
To get the mask aligned with the targets on the sky, at least three relatively bright acquisition stars should be selected. It is required to make square apertures for these stars, of 4 arcsec width.
The template image must be in FITS format and have the extension '.fits'. ASCII input files must have the extension '.coo'. Below is given information on how to run mosplate and where to put the template images and input files. This information is also available on the NOT web pages.