### JSAJOIN

Create a single tangent-plane NDF from a set of JSA tiles

#### Description:

This script pastes together one or more JSA tiles and then resamples the resulting montage onto a tangent-plane projection with square pixels and celestial north upwards. It can also restrict the output NDF to a specified sub-section of this montage.

By default, the output NDF contains all the data from all the tiles specified by parameter TILES. Alternatively, an existing NDF can be specified for parameter REGION, in which case the output NDF will contain only the data that falls within the supplied NDF. Another way to specify the bounds of the output NDF is to give the centre and radius of a circle on the sky using parameters CENTRE1, CENTRE2, RADIUS and SYSTEM.

The pixel size of the output may be specified by parameter PIXSIZE, but defaults to the nominal pixel size of the JSA tiles.

#### Usage:

jsajoin tiles out [centre1] [centre2] [radius] [system] [region] [pixsize] [retain]

#### Parameters:

The formatted RA or Galactic longitude at the centre of a circle that defines the required extent of the output NDF. See also CENTRE2 and RADIUS. The coordinate system is specified by parameter SYSTEM. It is only accessed if a null (!) value is supplied for parameter REGION. If a null value is supplied for both CENTRE1 and REGION, the output NDF will encompass all the data specified by parameter TILES. [!]
The formatted Dec or Galactic latitude at the centre of a circle that defines the required extent of the output NDF. See also CENTRE1 and RADIUS. The coordinate system is specified by parameter SYSTEM. It is only accessed if a null (!) value is supplied for parameter REGION and a non-null value is supplied for parameter CENTRE1.
Selects the tiling scheme to be used. The following instrument names are recognised (unambiguous abbreviations may be supplied): " SCUBA-2(450)" , " SCUBA-2(850)" , " ACSIS" , " DAS" . If the first input NDF contains JCMT data, the default value for this parameter is determined from the FITS headers in the input NDF. Otherwise, there is no default and an explicit value must be supplied. []
The celestial coordinate system used by the CENTRE1 and CENTRE2 parameters. It can be either " ICRS" or " Galactic" . The output NDF inherits this same system as its current WCS Frame. [" ICRS" ]