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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').
Advanced Search

To narrow the search results, use advanced search syntax. This allows for specifying which circular field to search (submitter, subject, and/or body). For additional information, refer to the advanced search documentation.

Advanced Search Examples (click to copy):

subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

871 results found.

  1. SGR 1808-20 (=H2802): A Possible new SGR
  2. SGR 1806-20, submm observations
  3. RXTE PCA Observations of SGR1806-20 Region
  4. GRBlog: Compilation of all GCN Circ. data
  5. IPN detection of renewed activity from SGR1806-20
  6. HETE detection of burst from SGR1806-20
  7. GRB030329 observed as a sudden ionospheric disturbance (SID)
  8. IPN triangulation of GRB030131 - CORRECTION
  9. IPN triangulation of GRB021219
  10. IPN detection of continued activity from SGR1806-20
  11. IPN detection of renewed activity from SGR1806-20
  12. IPN detection of continued SGR1900+14 activity
  13. IPN confirmation of the reactivation of SGR1900+14
  14. IPN detection of possible reactivation of SGR1900+14
  15. IPN triangulation of GRB021119 (annulus)
  16. IPN triangulation of bursts from SGR1900+14, November 1-2, 2002
  17. SGR1900+14 activity, November 2-4, 2002
  18. Detection of activity from SGR 1900+14 with the RXTE/PCA
  19. IPN triangulation of GRB021025 (annulus)
  20. IPN detection of a burst from SGR1900+14
  21. Gemini IR Detection of AXP 1E 2259+586 Post-Burst
  22. SGR-like X-ray Bursts from AXP 1E 2259+586: follow-up
  23. AXP 1E2259+586: quasi-simultaneous optical observation
  24. AXP 1E2259+586 optical observations
  25. SGR-like Bursts from the AXP 1E 2259+586
  26. IPN detection of possible bursts from SGR1806-20
  27. IPN triangulation of GRB020525
  28. XRF 020427: Sudden Ionospheric Disturbance (SID)
  29. Mars Odyssey joins the IPN
  30. IPN detection and localization of Cygnus X-1 flares
  31. RXTE Observations of SGR 1900+14
  32. SGR1900+14 activity
  33. IPN/HETE Detection of Bursts from SGR1900+14
  34. IPN detection of further activity from SGR1806-20
  35. Optical observation of SGR 1806-20 at the 6-m SAO telescope
  36. Probable SGR or Short Duration GRB Detected by HETE
  37. Dramatic Increase in the Rate of X-ray Bursts Reported by HETE
  38. Possible burst from SGR1806-20
  39. IPN detection of SGR1900+14
  40. X-ray precursors to the large flare from SGR 1900+14
  41. SGR 1900+14: No evidence of extended X-ray emission
  42. SGR 1900+14 : RXTE observations
  43. BeppoSAX/NFI Follow-up Observation of SGR 1900+14
  44. SGR1900+14
  45. SGR 1900+14: Correction to GCN 1049
  46. Millimeter observation of SGR 1900+14
  47. SGR 1900+14: Detection of extended X-ray emission
  48. Chandra Observations of SGR 1900+14
  49. SGR 1900+14, Chandra observations
  50. Chandra Observations of SGR 1900+14
  51. SGR1900+14, I-band observations
  52. IPN triangulation of GRB 001004
  53. SGR 1806-20 burst activity
  54. GRB 991216--Summary of RXTE Observations
  55. BATSE GRB trigger criteria
  56. X-ray/GRB 1SAX J0835.9+5118, BATSE Observation
  57. GRB990308 not a new SGR
  58. GRB990308, Possible new SGR~0209+70
  59. SGR1900+14, BeppoSAX-GRBM observations
  60. SGR1627-41
  61. SGR1627-41, RXTE/ASM observations
  62. Reduced error box of SGR 1627-41
  63. SGR 1627-41
  64. Discovery of a new SGR source, SGR1627-41
  65. SGR 1900+14
  66. SGR1900+14
  67. SGR1900+14
  68. BATSE on-board GRB trigger change
  69. IRAS 18119-1342 and the possible new SGR
  70. Possible new SGR from US Naval Observatory
  71. RXTE Observations of SGR 1814-13

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