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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"

22 results found.

  1. GRB 180418A: 15 GHz upper limits from AMI
  2. GRB 180418A: TAROT La Silla observatory early optical observations
  3. GRB 180418A: MITSuME Ishigakijima Optical Observation
  4. GRB 180418A : SQUEAN observations
  5. GRB 180418A: Further GROND observations
  6. GRB 180418A: Swift/UVOT Detection
  7. GRB 180418A: Continued RATIR Optical Observations
  8. GRB 180418A: Imaging of the optical afterglow with the 1.3 m DFOT and 3.6 m DOT in ARIES, India
  9. GRB 180418A GROND observations
  10. GRB 180418A: Xinglong TNT optical upper limit
  11. GRB 180418A: NOT optical observations
  12. GRB 180418A: Gemini-North imaging and spectroscopy
  13. GRB 180418A: Swift-BAT refined analysis
  14. GRB 180418A: 1.5m OSN optical observations
  15. GRB 180418A: Fermi GBM observation
  16. GRB 180418A: Swift-XRT refined Analysis
  17. GRB 180418A: RATIR Optical Observations
  18. GRB 180418A: Enhanced Swift-XRT position
  19. GRB 180418A: Swift-XRT observations
  20. GRB 180418A: LCO FTN afterglow confirmation
  21. GRB 180418A: KAIT Optical Afterglow Candidate
  22. GRB 180418A: Swift detection of a short burst

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Download all Circulars as a .tar.gz archive:
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