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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').

22 results found.

  1. GRB 150423A: GMG observation limit
  2. GRB 150423A: Chandra X-ray Observation
  3. GRB 150423A: JCMT SCUBA-2 sub-mm observation
  4. GRB 150423A: MITSuME Akeno Optical observation
  5. GRB 150423A: VLT/X-shooter spectroscopy and tentative redshift
  6. GRB 150423A: Continued RATIR optical afterglow monitoring
  7. GRB 150423A: TSHAO optical observations
  8. GRB 150423A: WHT observations
  9. GRB 150423A: Keck redshift of neighboring galaxy
  10. GRB 150423A: MITSuME Okayama upper limits
  11. GRB 150423A: UKIRT NIR observations
  12. GRB 150423A: Swift-BAT refined analysis
  13. GRB 150423A: Swift/UVOT Upper Limits
  14. GRB 150423A: VLT detection
  15. GRB 150423A: Swift-XRT refined Analysis
  16. GRB 150423A: RATIR optical afterglow monitoring
  17. GRB 150423A: Enhanced Swift-XRT position
  18. GRB 150423A: Keck optical afterglow confirmation
  19. GRB 150423A: GROND afterglow candidate
  20. GRB 150423A: KAIT Optical Upper Limit
  21. GRB 150423A: GROND observation
  22. GRB 150423A: Swift detection of a short burst

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