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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.

Lucene Examples (click to copy):

subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

23 results found.

  1. LIGO/Virgo S190426c: Lick/KAIT Follow-Up Observations
  2. GRB 081211B: Nearby cluster
  3. GRB 080503: 2nd Epoch Chandra X-ray Observations
  4. GRB 080503: Further HST imaging
  5. GRB 080503: Chandra Observation of X-ray Rebrightening or Flattening
  6. GRB 080503: Hubble Space Telescope Imaging
  7. GRB 080503: Fading in continued Gemini imaging
  8. GRB 080503: VLA radio upper limit
  9. GRB 080503: Observations from NOT
  10. GRB 080503: Slow-rise optical AG ?
  11. GRB 080503: No further optical rebrightening
  12. GRB 080503: Late-time Optical rebrightening (possible mini-SN) - correction
  13. GRB 080503: Late-time Optical rebrightening (possible mini-SN)
  14. GRB 080503, Swift-BAT lag and time-resolved spectral analysis
  15. GRB 080503: MITSuME Ishigakijima optical upper limits
  16. GRB080503: Swift/UVOT Upper Limits
  17. GRB080503 XRT refined analysis
  18. GRB 080503, Swift-BAT refined analysis
  19. GRB 080503: Enhanced Swift-XRT position
  20. GRB 080503: MITSuME Akeno optical upper limits
  21. GRB 080503: New candidate afterglow/host in Gemini imaging
  22. GRB 080503: Optical afterglow candidate and LRIS spectroscopy of the short burst
  23. GRB 080503: Swift detection of a short burst

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Download all Circulars as a .tar.gz archive:
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