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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"

815 results found.

  1. IPN Triangulation of GRB091120
  2. Konus-Wind observation of GRB 091120
  3. GRB 091120: MAXI GSC detection
  4. GRB 090926B: MAXI GSC detection
  5. GRB 090831A: Suzaku WAM observation of the prompt emission
  6. GRB 090831A: IPN Triangulation
  7. GRB 090831: MAXI GSC detection
  8. GRB 090621: Swift/UVOT Upper Limits
  9. GRB080916A: Refined Swift/UVOT Observations
  10. GRB 080703: UVOT Follow-Up Observation
  11. GRB 080310: Swift/UVOT Refined Analysis
  12. Transient 080109/ SN 2008D, metallicity of the host galaxy
  13. Swift/UVOT observations of GRB070721B optical afterglow.
  14. Swift/UVOT refined analysis of GRB070529
  15. GRB 060109: Swift/UVOT upper limits

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Download all Circulars as a .tar.gz archive:
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