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"11 results found.
- Correction to GCN Circular 23663: GRB 190109A: Swift UVOT Upper Limits
- GRB 190109A: Swift/UVOT Upper Limits
- GRB 190109A: Fermi GBM observation
- Correction to the GCN circ. 23654 / GRB 190109B: Mondy optical upper limit
- GRB 190109B: Mondy optical upper limit
- GRB 190109A: Swift-BAT refined analysis
- GRB190109A: MITSuME Akeno optical upper limits
- GRB 190109A: Swift-XRT refined Analysis
- GRB 190109A: Enhanced Swift-XRT position
- GRB 190109A: Prompt enhanced Swift-XRT position
- GRB 190109A: Swift detection of a burst