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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').

32051 results found.

  1. GRB980326 X-ray Observations
  2. GRB980326, optical observations
  3. GRB980326, optical observations
  4. GRB980329, Fading IR counterpart to radio source
  5. GRByymmdd, Announcement of automation
  6. GRB980326 IPN annulus
  7. GRB980329 sub-millimeter observations
  8. GRB980329 IPN annulus
  9. GRB980329 near-IR observations
  10. GRB980326 optical observations
  11. GRB980329 optical observations
  12. GRB980329 VLA observations
  13. GRB980329 near IR observations
  14. GRB980329 optical observations
  15. GRB980329 optical observations
  16. GRB980326 optical observations
  17. GRB980326 optical observations
  18. GRB970508 SAO RAS optical observations
  19. Optical Observations of GRB 970508
  20. GRB 971214: Redshift from Keck Observations
  21. Near-IR follow-up on GRB 971227
  22. GRB971214: Keck R & I-band Observations
  23. GRB 971227: Optical Observations
  24. Optical Observations of the GRB 971227 field
  25. Optical Observations on GRB 971227
  26. GRB971227: Plaskett R-band observations
  27. GRB 971227: Optical clarifications
  28. Optical Observations for GRB 971227
  29. GRB971227: Further CAHA R-band images
  30. GRB971227: LOTIS observations
  31. GRB 971227: CAHA R-band images
  32. GRB 971227: Optical observations
  33. Sub-millimeter Observations of GRB 971214 at the JCMT
  34. GRB 971214: EUVE Observations
  35. GRB 971214: Redshift from Keck Optical Observations
  36. GRB 971214: Redshift from Keck Optical Observations
  37. GRB 971214: Apache Point Observatory Optical Observations
  38. GRB 971214: KPNO Optical Observations
  39. Optical Observations of GRB 971214 at Keck
  40. GRB 971214: Optical Observations
  41. Radio Observations of GRB 971214 at the VLA
  42. GRB 971214: USNOFS Observations Summary
  43. GRB 971024: KPNO Optical Observations Summary
  44. GRB 971024: Refined analysis by USNOFS Observations
  45. GRB 971024: KPNO Optical Observations
  46. GRB 971024: USNO Observations
  47. GRB 970925: BATSE Localization
  48. IRAS 18119-1342 and the possible new SGR
  49. Possible new SGR from US Naval Observatory
  50. GRB 970828: Palomar Observations
  51. GRB 970228: Keck/LRIS Optical Observations

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