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 250823A: Swift-BAT refined analysis
- GRB 250823A: Swift-XRT refined Analysis
- GRB 250823A: COLIBRÍ optical observations
- GRB 250823A: SVOM/VT optical observation
- GRB 250823A: Swift/UVOT Detection
- GRB 250823A: NOT optical observations
- GRB 250823A: Fermi GBM Observation
- GRB 250823A: Enhanced Swift-XRT position
- GRB 250823A: LCOGT Optical Detection
- GRB 250823A: BOOTES6/DPRT early optical detection
- GRB 250823A: Liverpool Telescope optical detection
- GRB 250823A: Swift detection of a burst
- GRB 250823A: Fermi GBM Final Real-time Localization