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8.1 Introduction

This chapter describes the Standard Product Generation Pipeline , which converts the raw data telemetered from ISO into useful scientific data. It describes all the stages of the pipeline, the error propagation through it and any side-effects noted on the processed data.

The pipeline is composed of three parts:

tex2html_wrap_inline7035 Extracting the instrument data from the raw data stream into Edited Raw Data (ERD ) files. This process is a reformatting only and will not be discussed further.

tex2html_wrap_inline7035 ERD to Standard Processed Data (SPD ) stage, known as Derive-SPD . This involves removing all instrumental effects on timescales of less than 1 reset interval, converting detector readouts (voltages against time) into slopes  and assigning, where possible, wavelengths with detectors.

tex2html_wrap_inline7035 SPD to Auto-Analysis Results (AAR ) stage, known as Auto-Analysis . This further process the SPD removing instrumental effects on timescales of greater than 1 reset interval and converts slopes to fluxes.

In the course of Derive-SPD and Auto-Analysis several files are used that describe the behaviour of the instrument and its performance. These files are known, for historical reasons, as Cal-G  files. They contain such things as the conversion between scanner position and wavelength, voltages per second and fluxes, the separation between the three apertures etc.

K. Leech with contributions from
the SWS Instrument Dedicated Team (SIDT)
and the SWS Instrument Support Team (SIST)