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Field Center Coordinates

This panel is visible if Individual Pointing(s) has been selected in the Source panel. The number of pointings that can be defined is nominally 150 per Science Goal, distributed between multiple sources. In practice, more pointings can be created if the source list can be split into multiple clusters. It is possible to define multiple pointings per source, but each one must overlap such that they form a single mosaic. If multiple mosaics are required, they must be placed in separate Field Sources.

At the bottom of the panel are buttons which allow a user to add and delete pointings manually, but also to import and export them from and to an external ASCII file. The file format is very flexible and allows a user to write out the pointing positions in either offset or absolute coordinates and will automatically do the conversion between the two i.e. one can export in a different system to what is displayed. An example of the format for absolute coordinates in sexagesimal is shown here:
RA , Dec, Coordinate Type, Coordinate Units
--   This signals end of the header
 04:31:38.4369, 18:13:57.651,Absolute,Sexagesimal
 04:31:40.5426, 18:13:57.650,Absolute,Sexagesimal
 04:31:36.3312, 18:13:57.650,Absolute,Sexagesimal
The ``Absolute'' coordinate type can be combined with the units ``Sexagesimal'', ``Degrees'' or ``Radians'', whilst ``Offset'' pointings can be defined in ``Arcsecs'', ``Arcmin'' or ``Degrees''. Both the unit and coordinate type are case-insensitive. Galactic coordinates are not supported.


next up previous contents
Next: Rectangle Up: Field Setup Previous: Expected Source Properties   Contents
The ALMA OT Team, 2018 Sep 25