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.
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"
24 results found.
- GRB 250520A: Swift-BAT refined analysis
- GRB 250520A: Gemini-South optical afterglow detection
- GRB 250520A: 3 GHz MeerKAT Detection
- GRB 250520A: 10 GHz VLA Afterglow Confirmation
- GRB 250520A: GRBAlpha detection
- GRB 250520A: CALET Gamma-Ray Burst Monitor detection
- GRB 250520A: 10 GHz VLA radio source
- Konus-Wind detection of GRB 250520A (short/hard)
- GRB 250520A: VLT/FORS2 Optical Observation
- GRB 250520A: Swift/UVOT Upper Limits
- GRB 250520A: J-band observations with WINTER
- GRB 250520A: Gemini-South optical observations
- GRB 250520A: Swift-XRT refined Analysis
- GRB 250520A: REM optical/NIR early observations
- GRB 250520A:SVOM/VT optical candidate
- GRB 250520A: COLIBRÍ optical upper limit
- GRB 250520A: DDOTI Optical Upper Limit
- GRB 250520A: AstroSat CZTI detection of a short burst
- GRB 250520A: SVOM/GRM observation
- GRB 250520A: Enhanced Swift-XRT position
- GRB 250520A: GOTO optical upper limit
- GRB 250520A: Prompt enhanced Swift-XRT position
- GRB 250520A: Swift detection of a burst
- Swift GRB 250520A: Global MASTER-Net observations report