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.
Lucene Examples (click to copy):
subject:"Swift"body:"GRB"submitter:"Judith Racusin"16 results found.
- GRB 210207B: Prompt and very late time observations with HCT.
- GRB 210207B: GECAM detection
- GRB 210207B: Continued LCO Observations
- GRB 210207B: AstroSat CZTI detection
- GRB 210207B: Swift/UVOT Detection
- GRB 210207B: Swift-BAT refined analysis
- GRB 210207B: Insight-HXMT/HE detection
- GRB 210207B: LCO Optical Afterglow Detection
- GRB 210207B: KAIT Optical Observations
- GRB 210207B: AGILE observations
- GRB 210207B: Swift-XRT refined Analysis
- Konus-Wind detection of GRB 210207B
- GRB 210207B: AbAO optical upper limit
- GRB 210207B: Enhanced Swift-XRT position
- GRB 210207B: optical detection with 3.6m Devasthal Optical Telescope
- GRB 210207B: Swift detection of a burst with a bright optical counterpart