The Software Package for Astronomical Reductions with KMOS: SPARK

TL;DR

This paper details the SPARK software package for processing KMOS near-infrared spectroscopic data, focusing on calibration, interpolation, and flexure correction to produce high-quality science data.

Contribution

It introduces a comprehensive data reduction pipeline for KMOS, emphasizing minimal interpolation and effective flexure compensation, enhancing data quality and processing efficiency.

Findings

Single reconstruction approach reduces interpolation artifacts

Effective flexure measurement improves calibration accuracy

Comparison shows true 3D interpolation schemes outperform others

Abstract

KMOS is a multi-object near-infrared integral field spectrometer with 24 deployable cryogenic pick-off arms. Inevitably, data processing is a complex task that requires careful calibration and quality control. In this paper we describe all the steps involved in producing science-quality data products from the raw observations. In particular, we focus on the following issues: (i) the calibration scheme which produces maps of the spatial and spectral locations of all illuminated pixels on the detectors; (ii) our concept of minimising the number of interpolations, to the limiting case of a single reconstruction that simultaneously uses raw data from multiple exposures; (iii) a comparison of the various interpolation methods implemented, and an assessment of the performance of true 3D interpolation schemes; (iv) the way in which instrumental flexure is measured and compensated. We finish by presenting some examples of data processed using the pipeline.