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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').
  1. SAX J0840.7+2248 Optical Observations
  2. GRB 980425 optical observations
  3. GRB980425: optical obs.
  4. GRB980425: Radio Observations
  5. GRB 980425 optical observations
  6. report on BSAX observations of GRB980425
  7. GRB 980425 optical observations
  8. GRB 980329 ROSAT observation
  9. GRB980326 X-ray Observations
  10. GRB980326, optical observations
  11. GRB980326, optical observations
  12. GRB980329, Fading IR counterpart to radio source
  13. GRByymmdd, Announcement of automation
  14. GRB980326 IPN annulus
  15. GRB980329
  16. GRB980329 Keck K-band observations
  17. GRB980329 sub-millimeter observations
  18. GRB980329 IPN annulus
  19. GRB980329 optical observations
  20. GRB980329 near-IR observations
  21. GRB980329 near-IR observations
  22. GRB980329 optical observations
  23. GRB980329 infrared observations
  24. GRB980329 optical observations
  25. GRB980326 optical observations
  26. GRB980329 optical observations
  27. GRB980329 VLA observations
  28. GRB980329 near IR observations
  29. GRB980329 optical observations
  30. GRB980329 optical observations
  31. GRB980329 optical observations
  32. GRB980326 optical observations
  33. GRB980326 optical observations
  34. GRB980326 optical observations
  35. GRB980326 optical observations
  36. GRB970508 SAO RAS optical observations
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