SPAN: A cross-platform Python GUI software for optical and near-infrared spectral analysis

TL;DR

SPAN is a cross-platform Python GUI tool that consolidates spectral analysis tasks for optical and near-infrared data, making complex workflows accessible without coding and validated against existing methods.

Contribution

It introduces a unified, user-friendly GUI software for spectral analysis that integrates multiple tools and routines, including pPXF, within a single platform for the first time.

Findings

SPAn simplifies spectral analysis workflows.

SPAn produces results consistent with existing pipelines.

The software is accessible on multiple operating systems.

Abstract

The increasing availability of high-quality optical and near-infrared spectroscopic data, as well as advances in modelling techniques, have greatly expanded the scientific potential of spectroscopic studies. However, the software tools needed to fully exploit this potential often remain fragmented across multiple specialised packages, requiring scripting skills and manual integration to handle complex workflows. In this paper we present SPAN (SPectral ANalysis), a cross-platform, Python-based Graphical User Interface (GUI) software that unifies the essential tools for modern spectral analysis within a single, user-friendly environment. While SPAN can be used with a variety of spectroscopic targets, its primary focus is the analysis of unresolved galaxy spectra. SPAN allows users to extract 1D spectra from FITS images and datacubes, perform spectral processing (e.g. Doppler correction, continuum modelling, denoising), and carry out detailed analyses, including line-strength measurements, stellar and gas kinematics, and stellar population studies, using both built-in routines and the widely adopted pPXF algorithm for full spectral fitting. It runs natively on Windows, Linux, macOS, and Android, and is fully task-driven, requiring no prior coding experience. We validate SPAN by comparing its output with existing pipelines and literature studies. By offering a flexible, accessible, and well integrated environment, SPAN simplifies and accelerates the spectral analysis workflow, while maintaining scientific accuracy.