GCN Circulars
GCN Circulars are rapid astronomical bulletins submitted by and distributed to community members worldwide. They are used to share discoveries, observations, quantitative near-term predictions, requests for follow-up observations, or future observing plans related to high-energy, multi-messenger, and variable or transient astrophysical events. See the documentation for help with subscribing to or submitting Circulars.
Search for Circulars by submitter, subject, or body text (e.g. 'Fermi GRB').
To navigate to a specific circular, enter the associated Circular ID (e.g. 'gcn123', 'Circular 123', or '123').
To navigate to a specific circular, enter the associated Circular ID (e.g. 'gcn123', 'Circular 123', or '123').
Advanced Search
To narrow the search results, use advanced search syntax. This allows for specifying which circular field to search (submitter, subject, and/or body). For additional information, refer to the advanced search documentation.
Lucene Examples (click to copy):
subject:"Swift"body:"GRB"submitter:"Judith Racusin"12 results found.
- GRB 230816A: Swift-BAT refined analysis
- GRB 230816A: SVOM/C-GFT optical detection
- GRB 230816A: Swift-XRT refined Analysis
- GRB 230816A: Osservatorio Astronomico "Nastro Verde" optical observations
- GRB 230816A: Enhanced Swift-XRT position
- GRB230816A: Possible host and GIT detection of optical counterpart
- GRB 230816A: Tautenburg observations
- GRB 230816A: AKO Optical Observations
- GRB 230816A: TShAO and Assy optical observations
- GRB 230816A: SAO RAS optical observations
- GRB 230816A: Nanshan/HMT optical afterglow detection
- GRB 230816A: Swift detection of a burst