Large Language Model Driven Analysis of General Coordinates Network (GCN) Circulars

The General Coordinates Network (GCN) is NASA's time-domain and multi-messenger alert system. GCN distributes two data products - automated ``Notices,'' and human-generated ``Circulars,'' that report the observations of high-energy and multi-messenger astronomical transients. The flexible and non-structured format of GCN Circulars, comprising of more than 40500 Circulars accumulated over three decades, makes it challenging to manually extract observational information, such as redshift or observed wavebands. In this work, we employ large language models (LLMs) to facilitate the automated parsing of transient reports. We develop a neural topic modeling pipeline with open-source tools for the automatic clustering and summarization of astrophysical topics in the Circulars database. Using neural topic modeling and contrastive fine-tuning, we classify Circulars based on their observation wavebands and messengers. Additionally, we separate gravitational wave (GW) event clusters and their electromagnetic (EM) counterparts from the Circulars database. Finally, using the open-source Mistral model, we implement a system to automatically extract gamma-ray burst (GRB) redshift information from the Circulars archive, without the need for any training. Evaluation against the manually curated Neil Gehrels Swift Observatory GRB table shows that our simple system, with the help of prompt-tuning, output parsing, and retrieval augmented generation (RAG), can achieve an accuracy of 97.2 % for redshift-containing Circulars. Our neural search enhanced RAG pipeline accurately retrieved 96.8 % of redshift circulars from the manually curated database. Our study demonstrates the potential of LLMs, to automate and enhance astronomical text mining, and provides a foundation work for future advances in transient alert analysis.