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SCANPI and SUPERSCANPI can be accessed on-line through IRSA at:

http://irsa.ipac.caltech .edu/applications/Scanpi

This service supports single source and batch (multiple source) processing.

SCANPI performs scan coaddition of the IRAS raw survey data. SCANPI is useful for:

  • obtaining fluxes for point sources or slightly extended sources.
  • obtaining fluxes for confused or faint sources.
  • estimating true local upper limits.
  • diagnosing source extent.

Note: the sensitivity gain over the Point Source Catalog is comparable to that obtained from image coadds: about a factor of 2 to 5, depending on the local noise and number of scans crossing the target position.

SCANPI coadds scans which all passed over a specific target position.

SUPERSCANPI uses exactly the same processing steps as SCANPI, but coadds scans from a number of different target positions. SUPERSCANPI can thus be used to make general flux estimates for classes of faint objects.

SCANPI is the best tool for getting fluxes of slightly extended sources, however, when run in the default mode, it cannot be expected to give accurate fluxes for sources that are larger than approximately half the detector cross-scan width (~ 2.5'). SCANPI does allow flexibility in selecting scans for coaddition, but even special SCANPI reprocessing will not produce accurate fluxes for sources larger than about 4' - for sources that extended, image data products (e.g. FRESCO) will be more accurate.

Flux estimation is best performed on target positions which are accurate to within 15".

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(ISSA Processing Notes) (SCANPI Processing Notes)