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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').

20 results found.

  1. GRB 100424A: Keck host detection and VLT/X-shooter redshift
  2. GRB 100424a. Radio observations
  3. GRB 100424A: CrAO optical observations
  4. GRB 100424A: NIR Afterglow Confirmation
  5. GRB 100424A: Gemini/NIRI H-band observations
  6. GRB 100424A: Swift/UVOT Upper Limits
  7. GRB 100424A: Liverpool Telescope Upper Limits
  8. GRB 100424A: Gemini/NIRI Candidate Afterglow
  9. GRB 100424A: D50 optical limits
  10. GRB100424A: MITSuME optical upper limits
  11. GRB 100424A : Lulin early z'-band upper limit
  12. GRB 100424A: GROND Upper Limits
  13. GRB 100424A: PAIRITEL NIR Upper Limits
  14. GRB 100424A: Swift-XRT refined analysis
  15. GRB 100424A: WHT z-band observations
  16. GRB 100424A: NOT optical observations
  17. GRB 100424A, Swift-BAT refined analysis
  18. GRB 100424A: Enhanced Swift-XRT position
  19. GRB 100424A: Prompt enhanced Swift-XRT position.
  20. GRB 100424A: Swift detection of a burst


Download all Circulars as a .tar.gz archive:
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