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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"

914 results found.

  1. GRB 090926B: MAXI GSC detection
  2. GRB 090831A: Suzaku WAM observation of the prompt emission
  3. GRB 090831A: IPN Triangulation
  4. GRB 090831: MAXI GSC detection
  5. GRB 090814C: Fermi GBM detection
  6. GRB 090813: Fermi GBM observation
  7. GRB 090728: Swift/UVOT Upper Limits
  8. GRB 090718B: Fermi GBM detection
  9. GRB 090222: Fermi GBM detection
  10. GRB081104: Swift/UVOT Upper Limits
  11. GRB 080928: Swift/UVOT observations
  12. GRB 060510B: Swift/UVOT Upper Limits
  13. GRB 050904: TAROT optical measurements
  14. HST/STIS observations of the host galaxy of GRB 980329

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Download all Circulars as a .tar.gz archive:
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