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"14 results found.
- GRB 090621B: MAGIC telescope GeV observation
- GRB 090621B: MTM-500 optical observations
- GRB 090621B: GRT Optical Observation
- GRB 090621B: Fermi GBM detection
- GRB 090621B: I-band observations from 1.23m CAHA
- GRB 090621B: Gemini spectrum of afterglow candidate
- GRB 090621B: P60 Observations
- GRB 090621B: VLA observations
- GRB 090621B: Swift/UVOT Upper Limits
- GRB 090621B: Swift-BAT refined analysis
- GRB 090621B: Swift-XRT refined analysis
- GRB 090621B: RTT150 optical observations
- GRB 090621B: Optical Observations
- GRB 090621B: Swift detection of a short hard burst