Multi-segment and Echelle stellar spectra processing issues and how to solve them

TL;DR

This paper discusses methods to improve flux calibration quality of stellar spectra, using examples from NIR Echelle and UV-optical spectra, achieving 1-2% calibration accuracy for stellar population synthesis.

Contribution

It introduces procedures to enhance flux calibration quality of stellar spectra, demonstrated on NIR and UV-optical data, reaching high calibration precision.

Findings

Achieved 1-2% spectrophotometric calibration accuracy.

Improved flux calibration procedures for stellar spectra.

Validated methods on NIR and UV-optical spectra.

Abstract

High-quality stellar spectra are in great demand now - they are the most important ingredient in the stellar population synthesis to study galaxies and star clusters. Here we describe the procedures to increase the quality of flux calibration of stellar spectra. We use examples of NIR intermediate-resolution Echelle spectra collected with the Folded InfraRed Echellete (R~6500, Magellan Baade) and high-resolution UV-optical spectra observed with UVES (R~80000, ESO VLT). By using these procedures, we achieved the quality of the global spectrophotometric calibration as good as 1-2%, which fulfills the requirements for the quality of stellar spectra intended to be used in the stellar population synthesis