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 240122A: ATCA detection of radio counterpart
- GRB 240122A: Swift/UVOT Upper Limits
- GRB 240122A: BOOTES-2/TELMA optical upper limit and 1.5m OSN detection
- GRB 240122A: Swift-XRT afterglow detection
- GRB 240122A: VLT/X-shooter redshift confirmation
- GRB 240122A: Redshift from OSIRIS+/GTC
- GRB 240122A: LT non-detection of GOTO candidate counterpart confirms fading
- GRB 240122A: GOTO optical counterpart candidate
- GRB 240122A: Tiled Swift observations
- GRB 240122A: MAXI/GSC detection