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.
Advanced Search Examples (click to copy):
subject:"Swift"body:"GRB"submitter:"Judith Racusin"13 results found.
- GRB 250419a: Continued Liverpool Telescope observations
- GRB 250419A: SVOM/ECLAIRs refined analysis
- GRB 250419A: Mephisto Multi-band Optical Detection
- GRB 250419A: Liverpool Telescope observations
- GRB 250419A: LCO optical observation
- GRB 250419A: SVOM/VT optical continuous observations
- GRB 250419A: Mondy and AbAO Optical Observations
- GRB 250419A: AKO Optical Afterglow Detection
- GRB 250419A: MASTER optical afterglow observation
- GRB 250419A: Swift-XRT localisation
- GRB 250419A: VLT/X-shooter spectroscopic redshift z = 0.845
- GRB 250419A: Swift-XRT refined Analysis
- GRB 250419A: SVOM/COLIBRÍ (FM-GFT) Detection of the Optical Counterpart