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"13 results found.
- GRB 200306C: Liverpool Telescope observations
- GRB 200303A: Fermi GBM observation
- GRB 200303A: Swift-XRT refined Analysis
- GRB 200303A: Swift-BAT refined analysis
- GRB 200303A: NOT optical observations
- GRB 200303A: Swift/UVOT Upper Limits
- GRB 200303A: FRAM-ORM optical limit
- GRB 200303A: GOTO observations upper limit
- GRB 200303A: Optical limit from CAHA
- GRB 200303A: CALET Gamma-Ray Burst Monitor detection
- GRB 200303A: Enhanced Swift-XRT position
- GRB 200303A: Swift detection of a burst
- GRB 200303A: Fermi GBM Final Real-time Localization