next up previous contents index
Next: Rectangular Field Up: Target Types for Science Previous: Target Types for Science   Contents   Index

Multiple Single Point Fields

For the Multiple single point fields target type, the user candefine one or more sources. For each source field and pointingparameters a new tab is created in the Source panel. Adding morefields is done via the Add Source button at the bottom of thepage.

For each source, multiple pointing centres can be specified byclicking the Add button in the Field Center Coordinates panel. The positions of the pointings can be entered into this panelin either absolute or relative (to the source position) coordinates.

Alternatively, pointings can be added using the FOV icon in thetoolbar above the image display - clicking in the image display willcreate the new pointing and a circle and a plus marker will becomevisible. The plus indicates the pointing position; the size of thecircle represents the FOV. To adjust a pointing position select thepointing position using the left mouse button. The pointing marker inthe image display will turn grey and can be dragged.

As mentioned above, these parameters are identical to those in theField Setup form. For relative as well absolute field centrecoordinates, when moving the pointing position in the image displaythe corresponding fields values in the form will also change. In thecase of relative pointing coordinates, when moving the source positionin the image display the pointing position will also change.

In order to calculate the FOV the frequency and the antenna diameterneed to be specified. This can be done in the FOV Parameters panel below the image display. To tell the Visual Spatial Editor whichfrequency is to be used, one needs to specify a frequency in the Frequency used field. In case the frequency has already beendefined, the Refresh button can be used. When this button isclicked, the OT gets the frequency from the Spectral Setup form.


next up previous contents index
Next: Rectangular Field Up: Target Types for Science Previous: Target Types for Science   Contents   Index
The ALMA OT Team, 2011 May 20