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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').
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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.

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subject:"Swift"
body:"GRB"
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603 results found.

  1. VLA observations of SGR 1806-20
  2. SGR1806-20: RXTE-PCA observation of the 041227 super-flare
  3. Detection of the SGR 1806-20 giant outburst back-scattered by the
  4. The giant outburst from SGR 1806-20
  5. Giant flare from SGR 1806-20 detected by INTEGRAL
  6. Very high activity of SGR 1806-20
  7. Summary of the recent bursts from SGR 1806-20
  8. IBAS GRB Alert # 2034
  9. Bright bursts from SGR1806-20
  10. Konus-Wind observation of a series SGR 1806-20 bursts on 041005
  11. Bursts from SGR 1806-20: Preliminary INTEGRAL results
  12. Very strong outburst from SGR 1806-20 detected with INTEGRAL
  13. SGR 1806-20 still active
  14. An intense burst from SGR1806-20
  15. Very bright burst detected from SGR 1806-20
  16. Increase of SGR 1806-20 activity
  17. Bursting activity from SGR 1806-20 detected with IBAS
  18. Ongoing activity of SGR 1806-20
  19. GRB040706:observation at University of Miyazaki
  20. SGR 1806-20: no IR variability of the proposed counterparts
  21. SGR 1806-20, potential NIR counterpart
  22. Activivty of SGR 1806-20
  23. IBAS GRB Alerts n.1785 to 1791
  24. Summary of recent bursts from SGR 1806-20 detected by INTEGRAL
  25. IBAS GRB Alert 1694
  26. IBAS GRB alerts 1679, 1680, 1681
  27. IBAS results on a burst from SGR1806-20
  28. IBAS alert 1180 refers to a burst from SGR 1806-20
  29. Ongoing Bursting Activity from SGR 1806-20 detected with IBAS
  30. SGR1806-20 bursts on 031008. Helicon detection and small error box.
  31. SGR 1806-20 bursts with INTEGRAL and IBAS announcement on Soft Gamma-Ray Repeaters
  32. A burst from SGR 1806-20 detected with IBAS
  33. IPN triangulation of GRB030926 (short/hard; large error box)
  34. IBAS detection of bursts from SGR 1806-20
  35. Radio Observations of SGR1806-20
  36. INTEGRAL ToO OBSERVATIONS OF SGR1806-20: CALL FOR CORRELATED OBSERVATIONS
  37. Summary of recent IPN and HETE detections of SGR bursts
  38. Clarification of GCN 2354 on SGR1806-20
  39. IPN detection of continued activity from SGR1806-20
  40. 030813 SGR event (Konus-Wind observation)
  41. SGR 1808-20 (=H2802): A Possible new SGR
  42. SGR 1806-20, submm observations
  43. RXTE PCA Observations of SGR1806-20 Region
  44. HETE detection of burst from SGR1806-20
  45. GRB030329 observed as a sudden ionospheric disturbance (SID)
  46. IPN triangulation of GRB021219
  47. IPN detection of continued activity from SGR1806-20
  48. IPN detection of renewed activity from SGR1806-20
  49. IPN detection of continued SGR1900+14 activity
  50. IPN confirmation of the reactivation of SGR1900+14
  51. IPN detection of possible reactivation of SGR1900+14
  52. IPN triangulation of bursts from SGR1900+14, November 1-2, 2002
  53. SGR1900+14 activity, November 2-4, 2002
  54. Detection of activity from SGR 1900+14 with the RXTE/PCA
  55. IPN detection of a burst from SGR1900+14
  56. Gemini IR Detection of AXP 1E 2259+586 Post-Burst
  57. SGR-like X-ray Bursts from AXP 1E 2259+586: follow-up
  58. AXP 1E2259+586: quasi-simultaneous optical observation
  59. AXP 1E2259+586 optical observations
  60. SGR-like Bursts from the AXP 1E 2259+586
  61. IPN detection of possible bursts from SGR1806-20
  62. XRF 020427: Sudden Ionospheric Disturbance (SID)
  63. Mars Odyssey joins the IPN
  64. IPN detection and localization of Cygnus X-1 flares
  65. RXTE Observations of SGR 1900+14
  66. SGR1900+14 activity
  67. IPN/HETE Detection of Bursts from SGR1900+14
  68. IPN detection of further activity from SGR1806-20
  69. Optical observation of SGR 1806-20 at the 6-m SAO telescope
  70. Probable SGR or Short Duration GRB Detected by HETE
  71. Dramatic Increase in the Rate of X-ray Bursts Reported by HETE
  72. Possible burst from SGR1806-20
  73. IPN detection of SGR1900+14
  74. X-ray precursors to the large flare from SGR 1900+14
  75. SGR 1900+14: No evidence of extended X-ray emission
  76. SGR 1900+14 : RXTE observations
  77. BeppoSAX/NFI Follow-up Observation of SGR 1900+14
  78. SGR1900+14
  79. SGR 1900+14: Correction to GCN 1049
  80. Millimeter observation of SGR 1900+14
  81. SGR 1900+14: Detection of extended X-ray emission
  82. Chandra Observations of SGR 1900+14
  83. SGR 1900+14, Chandra observations
  84. Chandra Observations of SGR 1900+14
  85. SGR1900+14, I-band observations
  86. SGR 1806-20 burst activity
  87. BATSE GRB trigger criteria
  88. X-ray/GRB 1SAX J0835.9+5118, BATSE Observation
  89. GRB990308 not a new SGR
  90. GRB990308, Possible new SGR~0209+70
  91. SGR1900+14, BeppoSAX-GRBM observations
  92. SGR1627-41
  93. SGR1627-41, RXTE/ASM observations
  94. Reduced error box of SGR 1627-41
  95. SGR 1627-41
  96. Discovery of a new SGR source, SGR1627-41
  97. SGR 1900+14
  98. SGR1900+14
  99. SGR1900+14
  100. BATSE on-board GRB trigger change

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