PFS 2D Pipeline Overview

The latest PFS 2D data reduction pipeline (DRP) is now based on the third generation (Gen3) LSST middleware. The PFS pipeline organizes data using key terms:

  • visit refers to a unique exposure identifier.

  • spectrograph defines the spectrograph module with an integer ranging from 1–4.

  • arm defines the spectrograph's blue, red, near-IR, and medium-resolution red arms (b, r, n, m).

  • catId specifies the catalog source of an object.

  • objId is a unique (within a catalog) 64-bit identifier for an astronomical source.

  • pfsDesignId encodes the fiber configuration.

  • pfsVisitHash uniquely defines a set of combined visits.

More details can be found in Appendix.

PFS 2D DRP Workflow

The PFS 2D DRP workflow is shown in the flowchart below.

PFS 2D DRP Workflow Flowchart

Products

  • pfsArm: These are wavelength-calibrated but not sky subtracted or flux calibrated single spectra from a single visit and a single arm.
  • pfsMerged: These are arm-merged, wavelength calibrated and sky subtracted (but not flux calibrated) spectra from a single visit.
  • pfsCalibrated: These are flux-calibrated, arm-merged, wavelength calibrated, and sky subtracted spectra from a single visit.
  • pfsCoadd: These are coadded spectra, and the final products for science.