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GCN Circulars

GCN Circulars are rapid bulletins submitted by and distributed to the community. 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').
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"

7 results found.

  1. GRB 200306A: Swift/UVOT Upper Limits
  2. GRB 200306A: Swift-BAT refined analysis
  3. GRB 200306A: RATIR Optical Observations
  4. GRB 200306A: AstroSat CZTI detection
  5. GRB 200306A: Swift-XRT refined Analysis
  6. GRB 200306A: Potential LCO Optical Afterglow Detection
  7. GRB 200306A: Swift detection of a burst

Advanced

Download all Circulars as a .tar.gz archive (updated once a day):
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