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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').

586 results found.

  1. Ongoing activity of SGR 1806-20
  2. GRB040706:observation at University of Miyazaki
  3. SGR 1806-20: no IR variability of the proposed counterparts
  4. SGR 1806-20, potential NIR counterpart
  5. Activivty of SGR 1806-20
  6. IBAS GRB Alerts n.1785 to 1791
  7. Summary of recent bursts from SGR 1806-20 detected by INTEGRAL
  8. IBAS GRB Alert 1694
  9. IBAS GRB alerts 1679, 1680, 1681
  10. IBAS results on a burst from SGR1806-20
  11. IBAS alert 1180 refers to a burst from SGR 1806-20
  12. Ongoing Bursting Activity from SGR 1806-20 detected with IBAS
  13. SGR1806-20 bursts on 031008. Helicon detection and small error box.
  14. SGR 1806-20 bursts with INTEGRAL and IBAS announcement on Soft Gamma-Ray Repeaters
  15. A burst from SGR 1806-20 detected with IBAS
  16. IPN triangulation of GRB030926 (short/hard; large error box)
  17. IBAS detection of bursts from SGR 1806-20
  18. Radio Observations of SGR1806-20
  19. INTEGRAL ToO OBSERVATIONS OF SGR1806-20: CALL FOR CORRELATED OBSERVATIONS
  20. Summary of recent IPN and HETE detections of SGR bursts
  21. Clarification of GCN 2354 on SGR1806-20
  22. IPN detection of continued activity from SGR1806-20
  23. 030813 SGR event (Konus-Wind observation)
  24. SGR 1808-20 (=H2802): A Possible new SGR
  25. SGR 1806-20, submm observations
  26. RXTE PCA Observations of SGR1806-20 Region
  27. HETE detection of burst from SGR1806-20
  28. GRB030329 observed as a sudden ionospheric disturbance (SID)
  29. IPN triangulation of GRB021219
  30. IPN detection of continued activity from SGR1806-20
  31. IPN detection of renewed activity from SGR1806-20
  32. IPN detection of continued SGR1900+14 activity
  33. IPN confirmation of the reactivation of SGR1900+14
  34. IPN detection of possible reactivation of SGR1900+14
  35. IPN triangulation of bursts from SGR1900+14, November 1-2, 2002
  36. SGR1900+14 activity, November 2-4, 2002
  37. Detection of activity from SGR 1900+14 with the RXTE/PCA
  38. IPN detection of a burst from SGR1900+14
  39. Gemini IR Detection of AXP 1E 2259+586 Post-Burst
  40. SGR-like X-ray Bursts from AXP 1E 2259+586: follow-up
  41. AXP 1E2259+586: quasi-simultaneous optical observation
  42. AXP 1E2259+586 optical observations
  43. SGR-like Bursts from the AXP 1E 2259+586
  44. IPN detection of possible bursts from SGR1806-20
  45. XRF 020427: Sudden Ionospheric Disturbance (SID)
  46. Mars Odyssey joins the IPN
  47. IPN detection and localization of Cygnus X-1 flares
  48. RXTE Observations of SGR 1900+14
  49. SGR1900+14 activity
  50. IPN/HETE Detection of Bursts from SGR1900+14
  51. IPN detection of further activity from SGR1806-20
  52. Optical observation of SGR 1806-20 at the 6-m SAO telescope
  53. Probable SGR or Short Duration GRB Detected by HETE
  54. Dramatic Increase in the Rate of X-ray Bursts Reported by HETE
  55. Possible burst from SGR1806-20
  56. IPN detection of SGR1900+14
  57. X-ray precursors to the large flare from SGR 1900+14
  58. SGR 1900+14: No evidence of extended X-ray emission
  59. SGR 1900+14 : RXTE observations
  60. BeppoSAX/NFI Follow-up Observation of SGR 1900+14
  61. SGR1900+14
  62. SGR 1900+14: Correction to GCN 1049
  63. Millimeter observation of SGR 1900+14
  64. SGR 1900+14: Detection of extended X-ray emission
  65. Chandra Observations of SGR 1900+14
  66. SGR 1900+14, Chandra observations
  67. Chandra Observations of SGR 1900+14
  68. SGR1900+14, I-band observations
  69. SGR 1806-20 burst activity
  70. BATSE GRB trigger criteria
  71. X-ray/GRB 1SAX J0835.9+5118, BATSE Observation
  72. GRB990308 not a new SGR
  73. GRB990308, Possible new SGR~0209+70
  74. SGR1900+14, BeppoSAX-GRBM observations
  75. SGR1627-41
  76. SGR1627-41, RXTE/ASM observations
  77. Reduced error box of SGR 1627-41
  78. SGR 1627-41
  79. Discovery of a new SGR source, SGR1627-41
  80. SGR 1900+14
  81. SGR1900+14
  82. SGR1900+14
  83. BATSE on-board GRB trigger change
  84. Untitled
  85. Possible new SGR from US Naval Observatory
  86. RXTE Observations of SGR 1814-13

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