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Bolometer observing methods

Target source observations

Depending on the source size, a target is usually observed through a raster map in spiral mode or an OTF map. By introducing offsets from the catalog position (mosaic), also large or irregularly shaped objects can be mapped with a homogenous noise over the area of interest. See further below to know when this mosaic technique is recommended.

Calibration observations

In addition, there exist a few observing methods especially for calibration observations.

Absolute flux calibration is performed by a raster map in spiral mode on a planet or a secondary calibrator. See the calibration section for details.

Observing strategy depending on the target

The observing patterns described above can be customized in order to provide a homogenous coverage of the area of interest. In addition, LABOCA's reference channel can be changed to a more sensitive one than that in the geometric centre. In the following we give an overview over various observing strategies for various source sizes.