QhX / AGN Catalogue Portal – Technical Documentation

The QhX / AGN Catalogue Portal is a PHP-based web platform that serves as the technical interface to a secondary catalogue of active galactic nuclei (AGNs) extracted from Vera C. Rubin Observatory LSST Data Preview 1 (DP1) and processed with the Quasar harmonic eXplorer (QhX, v0.2.1) pipeline. The portal provides authenticated users with interactive catalogue search and browsing, object detail views, exploratory visualisation modules (sky and parameter-space views), and Virtual Observatory (VO) compatible data access via VOTable export for TOPCAT and a Simple Cone Search (SCS) endpoint for pyVO. Access to VO services is controlled through short-lived JWT tokens with database-backed audit trails and optional constraints (one-time use, IP locking). In addition, the portal implements a controlled in-kind ingestion workflow for externally contributed Parquet catalogues, including Docker-based Python validation, staging tables, and an auditable promotion mechanism into the canonical QhX tables. This Zenodo record provides a versioned, citable technical reference of the portal’s architecture, data model, security mechanisms, and ingestion pipeline to support reproducibility, maintainability, and transparent reuse by the broader community.