SED Machine IFU DRP Guide


This document is organized in two parts: Data where the necessary calibration and science data are described and data processing where the flow of data and pipeline intermediate results are described.

Daytime Calibration Data

The following data have generally been taken with the telescope parked in the SED Machine “stow position” (ADD COORDINATES HERE).

  1. Dome flat field lamp (featureless incandescent; 2 min warmup)

  2. Dome mercury arc lamp (2 min warmup)

  3. Dome cadmium arc lamp (10 min warmup)

  4. Dome xenon projector lamp (2 min warmup)

  5. 0-second bias exposure

  6. 120-s, 600-s Dark exposures

We need to experiment with the following data

  1. Flat field data at a variety of telescope positions (for pixel flats w/ flexure correction)

  2. More arc lamp data including: krypton, argon, neon, cadmium, and zinc

  3. Take high-resolution spectra of He+Neon lamp with (say DBSP) to measure line ratios

  4. Illuminate detector internal to instrument for pixel-level flat response.

Bad pixel mask

How will we identify bad pixels? The bad-pixel mask (BPM) must also be stored and used in all steps. Assume the bad pixel mask is an input into all pipeline steps. The BPM can change over time and thus must be labeled and updated every few months (years?).

Important FITS Headers

FITS headers are used to communicate with the pipeline and the end user. Important FITS headers are documented here.

  • GAIN – The gain in \(e-\)/ADU of the observation. When the observation is gain adjusted the gain is set to 1.0 and the comment of the GAIN header is set to the old GAIN value.

  • more here.