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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"

24 results found.

  1. GRB 180914B: RTT150 optical observations
  2. GRB 180914B: RTT150 optical observations
  3. INTEGRAL detections of the prompt gamma-ray emission of GRB 180914B
  4. GRB 180914B: OSN Detection and light curve/SED analysis
  5. GRB 180914B: OAJ multi-color follow-up
  6. GRB 180914B: DDOTI/OAN Detection and Confirmation of Fading
  7. GRB 180914B: GOTO optical detection
  8. GRB 180914B: AstroSat CZTI detection
  9. GRB 180914B : continued TSHAO optical observations
  10. GRB 180914B: VLT/X-shooter spectroscopic redshift
  11. GRB 180914B: MASTER OT automatic dtection
  12. GRB 180914B : TSHAO optical observations
  13. GRB 180914B: Continued RATIR Optical and NIR Observations
  14. GRB 180914B: AGILE/MCAL refined analysis
  15. GRB180914B: Swift UVOT detection of an optical afterglow
  16. Konus-Wind of the very bright GRB 180914B
  17. GRB 180914B: Optical counterpart observation from OAJ
  18. GRB 180914B: RATIR Optical and NIR Observations
  19. GRB 180914B: KAIT Optical Afterglow Candidate
  20. GRB 180914B: Swift-XRT afterglow detection
  21. GRB 180914B: Tiled Swift observations
  22. GRB 180914B: Fermi-LAT detection
  23. GRB 180914B: AGILE/GRID detection
  24. GRB 180914B: AGILE/MCAL detection of a burst

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