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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"

5 results found.

  1. GRB 151004A: Swift-XRT follow-up observations
  2. Trigger 657564 / GRB 151004A: Swift BAT and XRT refined analysis
  3. Trigger 657564 / GRB 151004A: Swift/UVOT Upper Limits
  4. Swift Trigger 657564: XRT prompt analysis
  5. Swift Trigger 657564: a probable GRB

Advanced

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