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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').
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. Correction to GCN 5278 & GCN 5279 (GRBs 060105 & 060109)
  2. GRB 060109: Upper Limit on Host Galaxy
  3. GRB 060109: Swift-BAT refined analysis
  4. Correction to GRB 060109 XRT analysis
  5. GRB 060109: Refined Swift-XRT analysis
  6. GRB 060109: Swift/UVOT upper limits
  7. GRB060109, optical observation
  8. Swift UVOT correction to GCN 4455
  9. GRB 060109: Swift Detection of a long burst

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Download all Circulars as a .tar.gz archive:
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