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"10 results found.
- GRB 210618A: 1.5m OSN optical upper limit
- GRB 210618A: Swift-XRT afterglow detection
- GRB 210618A: Swift/UVOT Upper Limits
- GRB 210618A: BOOTES-2/TELMA optical upper limit
- GRB 210618A: Swift-BAT refined analysis
- GRB 210618A: Fermi GBM observation
- GRB 210618A: Swift-XRT observations
- GRB 210618A: DDOTI upper limit for the optical afterglow
- GRB 210618A: Swift detection of a burst
- GRB 210618A: Fermi GBM Final Real-time Localization