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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').

18 results found.

  1. GRB 091221: Swift/UVOT refined analysis
  2. GRB 091208B: Xinglong TNT optical observation
  3. GRB 091208B: GAO 150cm telescope Optical Observation
  4. GRB 091208B: optical observations
  5. GRB 091208B: Keck HIRES redshift confirmation
  6. GRB 091208B: GROND observations
  7. GRB 091208B: Swift-XRT refined analysis
  8. GRB091208B: Swift/UVOT refined analysis
  9. GRB 091208B: Fermi GBM observation
  10. GRB 091208B, Swift-BAT refined analysis
  11. GRB 091208B: Gemini-North redshift
  12. GRB 091208B: Faulkes Telescope North and South Optical Afterglow
  13. GRB 091208B: MITSuME Akeno Optical Observation
  14. GRB 091208B: Enhanced Swift-XRT position
  15. GRB 091208B: MITSuME Okayama Optical Observation
  16. GRB 091208B, RIMOTS optical upper limits
  17. GRB 091208B: Swift detection of a burst with an optical afterglow
  18. GRB 091208B: BOOTES-3 optical afterglow

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