StepCalibrate

class sofia_redux.instruments.hawc.steps.stepcalibrate.StepCalibrate

Bases: StepParent

Flux calibrate Stokes images.

This step multiplies the flux in each image by a calibration factor to convert to Jy/pixel units.

It is assumed that the input data have been opacity-corrected to a reference altitude and zenith angle, and that the factors were derived from flux standards that were similarly corrected. This step should be run after the sofia_redux.instruments.hawc.steps.StepOpacity pipeline step.

Calibration factors are tracked and applied by configuration files and algorithms in the sofia_redux.calibration package:

• sofia_redux.calibration.pipecal_config: pipecal_config

• sofia_redux.calibration.pipecal_util: get_fluxcal_factor, apply_fluxcal

Methods Summary

run()	Run the data reduction algorithm.
setup()	Set parameters and metadata for the pipeline step.

Methods Documentation

run()

Run the data reduction algorithm.

Because this step is single-in, single-out (SISO), self.datain must be a DataFits object. The output is also a DataFits object, stored in self.dataout.

The process is:

1. Retrieve a calibration factor from configuration files stored in the sofia_redux.calibration package.

2. Multiply flux and error images by the calibration factor. Multiply covariance images by the calibration factor squared.

3. Set the BUNIT keyword in each extension accordingly (to ‘Jy/pixel’ or ‘Jy2/pixel2’ for covariances).

setup()

Set parameters and metadata for the pipeline step.

Output files have PRODTYPE = ‘calibrate’, and are named with the step abbreviation ‘CAL’.

No parameters are currently defined for this step.