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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"

9 results found.

  1. GRB 230409B: 3.6m DOT near-infrared detection, afterglow confirmation
  2. GRB 230409B: Mondy optical upper limit
  3. GRB 230409B: OHP/T193 optical upper limit
  4. GRB 230409B: Swift-XRT refined Analysis
  5. GRB 230409B: Swift-BAT refined analysis
  6. Swift GRB 230409B: Global MASTER-Net observations report
  7. GRB 230409B: Swift/UVOT Detection
  8. GRB 230409B: Enhanced Swift-XRT position
  9. GRB 230409B: Swift detection of a burst

Advanced

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