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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"

827 results found.

  1. GRB 100704: Swift/UVOT Upper Limits
  2. XRF 100701A : MAXI/GSC detection of a probable XRF
  3. XRF 100616a : MAXI/GSC detection of a probable XRF
  4. GRB 100615A: Swift/UVOT Upper Limits
  5. GRB 100510A: Fermi GBM detection/observation
  6. GRB 100510A: MAXI/GSC detection
  7. GRB 100415A: MAXI/GSC detection of a probable GRB
  8. Short X-ray Transient detected by MAXI/GSC
  9. XRF 100315A: MAXI/GSC detection of a short X-ray transient
  10. Short X-ray Transient detected by MAXI/GSC
  11. Short X-ray Transient, RIMOTS optical upper limits
  12. Short X-ray Transient Detection by MAXI/GSC
  13. IPN Triangulation of GRB091120
  14. Konus-Wind observation of GRB 091120
  15. GRB 091120: MAXI GSC detection
  16. GRB 090926B: MAXI GSC detection
  17. GRB 090831A: Suzaku WAM observation of the prompt emission
  18. GRB 090831A: IPN Triangulation
  19. GRB 090831: MAXI GSC detection
  20. GRB 090621: Swift/UVOT Upper Limits
  21. GRB080916A: Refined Swift/UVOT Observations
  22. GRB 080703: UVOT Follow-Up Observation
  23. GRB 080310: Swift/UVOT Refined Analysis
  24. Transient 080109/ SN 2008D, metallicity of the host galaxy
  25. Swift/UVOT observations of GRB070721B optical afterglow.
  26. Swift/UVOT refined analysis of GRB070529
  27. GRB 060109: Swift/UVOT upper limits

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