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"8 results found.
- GRB 181030A: Swift/UVOT Detection
- GRB 181030A, Swift-BAT refined analysis
- GRB 181030A: RATIR Optical and NIR Observations
- GRB 181030A: Swift-XRT refined Analysis
- GRB 181030A: MASTER Net OT detection
- GRB 181030A: Enhanced Swift-XRT position
- GRB 181030A: SAO RAS optical observations
- GRB 181030A: Swift detection of a burst with a possible optical counterpart