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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"

29 results found.

  1. BepiColombo MGNS joins the IPN
  2. GRB 190530A: Observation of the afterglow by NOEMA
  3. GRB 190530A: Further OAJ/OSN photometry and analysis
  4. GRB 190530A: optical follow-up observations at Konkoly
  5. GRB 190530A: R-band observation from HCT
  6. Konus-Wind observation of extremely bright GRB 190530A
  7. GRB 190530A: Insight-HXMT/HE detection
  8. GRB 190530A: Mondy and AbAO optical observations
  9. GRB 190530A: Konkoly optical observations of the afterglow
  10. GRB 190530A: SAO RAS optical observations
  11. GRB 190530A: Swift/UVOT Detection
  12. GRB 190530A: Steep afterglow decay found by OSN
  13. GRB 190530A: AbAO optical observations
  14. GRB 190530A: Xinglong 2.16m optical observation
  15. GRB 190530A: AstroSat CZTI detection
  16. GRB 190530A: optical afterglow detection by 5 MASTER telescopes
  17. GRB 190530A: Fermi GBM observation
  18. GRB 190530A: COATLI Optical Detection of the Fading Afterglow
  19. GRB 190530A: Swift-XRT afterglow detection
  20. GRB 190530A: GWAC-F30 optical detection
  21. GRB 190530A: OAJ optical detection
  22. GRB 190530A: NOT photometry and spectroscopy
  23. GRB 190530A: Bright afterglow confirmed by OSN
  24. GRB 190530A: AGILE/GRID analysis
  25. GRB 190530A: Swift ToO observations
  26. GRB 190530A: MASTER OT detection
  27. GRB 190530A: Fermi-LAT detection
  28. GRB 190530A: AGILE-MCAL detection
  29. GRB 190530A: Fermi GBM Final Real-time Localization

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