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.
jsajoin tiles out [centre1] [centre2] [radius] [system] [region] [pixsize]
[retain]
CENTRE1 = LITERAL (Read)
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. [!]
CENTRE2 = LITERAL (Read)
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.
INSTRUMENT = LITERAL (Read)
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. []
OUT = NDF (Read)
The output NDF.
PIXSIZE = _REAL (Read)
The pixel size to
use for the output NDF, in arc-seconds. Not used if an NDF is supplied for parameter
REGION. If a null (!) value is supplied, a default pixel size is used equal to the geometric mean
of the pixel dimensions in the middle tile specified by parameter TILES. [!]
RADIUS =
_DOUBLE (Read)
The radius of the circle that defines the required extent of the output NDF, in
arc-minutes. See also CENTRE1 and CENTRE2. It is only accessed if a null (!) value is
supplied for parameter REGION and a non-null value is supplied for parameter CENTRE1.
REGION = LITERAL (Read)
Specifies the required extent of the output NDF. It can be either
a text file holding an AST Region description, or an NDF. If it is an NDF, it also defines
the WCS and pixel grid of the output NDF. If a null (!) value is supplied, the region is
specified using parameter CENTRE1, CENTRE2 and RADIUS. [!]
RETAIN = _LOGICAL
(Read)
Should the temporary directory containing the intermediate files created by this
script be retained? If not, it will be deleted before the script exits. If retained, a message
will be displayed at the end specifying the path to the directory. [FALSE]
SYSTEM =
LITERAL (Read)
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"
]
TILES = NDF (Read)
A group of NDFs
each of which corresponds to a JSA tile. They should all relate to a single instrument.