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 190926A: Upper limit from CAHA 2.2m observation
- GRB 190926A: AbAO upper optical limit
- GRB 190926A: Swift-BAT refined analysis
- GRB 190926A: Upper Limit from OSN T150 Observation
- GRB 190926A: MITSuME Akeno optical upper limits
- GRB 190926A: Swift/UVOT Upper Limits
- GRB 190926A: KAIT Optical Upper Limit
- GRB 190926A: Swift-XRT refined Analysis
- GRB 190926A: Enhanced Swift-XRT position
- GRB 190926A: Swift detection of a burst