C3, A Command-line Catalogue Cross-match tool for large astrophysical catalogues

TL;DR

C3 is a versatile, multi-platform command-line tool that efficiently cross-matches large astrophysical catalogues, supporting various data formats, resolutions, and shapes, with high performance and reliability.

Contribution

The paper introduces C3, a novel command-line application that enhances large-scale astrophysical catalogue cross-matching with multi-core processing and flexible features.

Findings

C3 outperforms existing tools in efficiency and reliability.

Supports diverse catalogue formats and region shapes.

Demonstrates high scalability with real survey data.

Abstract

Modern Astrophysics is based on multi-wavelength data organized into large and heterogeneous catalogues. Hence, the need for efficient, reliable and scalable catalogue cross-matching methods plays a crucial role in the era of the petabyte scale. Furthermore, multi-band data have often very different angular resolution, requiring the highest generality of cross-matching features, mainly in terms of region shape and resolution. In this work we present $C^{3}$ (Command-line Catalogue Cross-match), a multi-platform application designed to efficiently cross-match massive catalogues. It is based on a multi-core parallel processing paradigm and conceived to be executed as a stand-alone command-line process or integrated within any generic data reduction/analysis pipeline, providing the maximum flexibility to the end-user, in terms of portability, parameter configuration, catalogue formats, angular resolution, region shapes, coordinate units and cross-matching types. Using real data, extracted from public surveys, we discuss the cross-matching capabilities and computing time efficiency also through a direct comparison with some publicly available tools, chosen among the most used within the community, and representative of different interface paradigms. We verified that the $C^{3}$ tool has excellent capabilities to perform an efficient and reliable cross-matching between large datasets. Although the elliptical cross-match and the parametric handling of angular orientation and offset are known concepts in the astrophysical context, their availability in the presented command-line tool makes $C^{3}$ competitive in the context of public astronomical tools.