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.
- IceCube-Cascade 250809A: Upper limits from a search for additional neutrino events in IceCube
- GRB 250809A: Swift-BAT refined analysis
- GRB 250809A: Swift/UVOT Detection
- Corrected Swift-XRT Refined Analysis of GRB 250809A
- GRB 250809A: Swift-XRT refined Analysis
- GRB 250809A: LCOGT Optical Upper Limits
- GRB 250809A: Prompt enhanced Swift-XRT position
- GRB 250809A: Swift detection of a gamma ray burst