GASV: A New VLBI analysis software for Geodesy and Astrometry

TL;DR

GASV is a new Python software for VLBI data analysis that simplifies processing and achieves accuracy comparable to established centers, supporting both individual and global geodetic and astrometric solutions.

Contribution

GASV introduces a user-friendly, versatile Python package for VLBI analysis, capable of both pipeline and interactive processing, with performance comparable to leading analysis centers.

Findings

GASV achieves parameter estimation accuracy similar to BKG and USNO.

Supports processing of standard VLBI data formats like HOPS and NGS.

Enables high-quality single-session and global long-term analyses.

Abstract

We present GASV, a novel Python-based software package specifically designed for the analysis of Very Long Baseline Interferometry (VLBI) data. Developed with ease of installation and user friendliness in mind, GASV supports both pipeline and interactive processing modes. The software processes VLBI baseline delays and rates in standard formats such as HOPS outputs and NGS card files to estimate key geodetic and astrometric parameters, including station coordinates, Earth Orientation Parameters, source coordinates, clock parameters, and atmospheric models. We evaluate the capabilities and performance of GASV, demonstrating that its parameter estimation accuracy for IVS INT, Regular, and CONT sessions is comparable to that achieved by the VLBI analysis centers at BKG and USNO. As a state-of-the-art tool, GASV not only enables high-quality single-session data processing but also but also supports global analyses of long-term SINEX files, generating Celestial Reference Frame and Terrestrial Reference Frame solutions with reliable accuracy.