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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"
submitter:"Judith Racusin"

598 results found.

  1. Very high activity of SGR 1806-20
  2. Summary of the recent bursts from SGR 1806-20
  3. IBAS GRB Alert # 2034
  4. Bright bursts from SGR1806-20
  5. Konus-Wind observation of a series SGR 1806-20 bursts on 041005
  6. Bursts from SGR 1806-20: Preliminary INTEGRAL results
  7. Very strong outburst from SGR 1806-20 detected with INTEGRAL
  8. SGR 1806-20 still active
  9. An intense burst from SGR1806-20
  10. Very bright burst detected from SGR 1806-20
  11. Increase of SGR 1806-20 activity
  12. Bursting activity from SGR 1806-20 detected with IBAS
  13. Ongoing activity of SGR 1806-20
  14. GRB040706:observation at University of Miyazaki
  15. SGR 1806-20: no IR variability of the proposed counterparts
  16. SGR 1806-20, potential NIR counterpart
  17. Activivty of SGR 1806-20
  18. IBAS GRB Alerts n.1785 to 1791
  19. Summary of recent bursts from SGR 1806-20 detected by INTEGRAL
  20. IBAS GRB Alert 1694
  21. IBAS GRB alerts 1679, 1680, 1681
  22. IBAS results on a burst from SGR1806-20
  23. IBAS alert 1180 refers to a burst from SGR 1806-20
  24. Ongoing Bursting Activity from SGR 1806-20 detected with IBAS
  25. SGR1806-20 bursts on 031008. Helicon detection and small error box.
  26. SGR 1806-20 bursts with INTEGRAL and IBAS announcement on Soft Gamma-Ray Repeaters
  27. A burst from SGR 1806-20 detected with IBAS
  28. IPN triangulation of GRB030926 (short/hard; large error box)
  29. IBAS detection of bursts from SGR 1806-20
  30. Radio Observations of SGR1806-20
  31. INTEGRAL ToO OBSERVATIONS OF SGR1806-20: CALL FOR CORRELATED OBSERVATIONS
  32. Summary of recent IPN and HETE detections of SGR bursts
  33. Clarification of GCN 2354 on SGR1806-20
  34. IPN detection of continued activity from SGR1806-20
  35. 030813 SGR event (Konus-Wind observation)
  36. SGR 1808-20 (=H2802): A Possible new SGR
  37. SGR 1806-20, submm observations
  38. RXTE PCA Observations of SGR1806-20 Region
  39. HETE detection of burst from SGR1806-20
  40. GRB030329 observed as a sudden ionospheric disturbance (SID)
  41. IPN triangulation of GRB021219
  42. IPN detection of continued activity from SGR1806-20
  43. IPN detection of renewed activity from SGR1806-20
  44. IPN detection of continued SGR1900+14 activity
  45. IPN confirmation of the reactivation of SGR1900+14
  46. IPN detection of possible reactivation of SGR1900+14
  47. IPN triangulation of bursts from SGR1900+14, November 1-2, 2002
  48. SGR1900+14 activity, November 2-4, 2002
  49. Detection of activity from SGR 1900+14 with the RXTE/PCA
  50. IPN detection of a burst from SGR1900+14
  51. Gemini IR Detection of AXP 1E 2259+586 Post-Burst
  52. SGR-like X-ray Bursts from AXP 1E 2259+586: follow-up
  53. AXP 1E2259+586: quasi-simultaneous optical observation
  54. AXP 1E2259+586 optical observations
  55. SGR-like Bursts from the AXP 1E 2259+586
  56. IPN detection of possible bursts from SGR1806-20
  57. XRF 020427: Sudden Ionospheric Disturbance (SID)
  58. Mars Odyssey joins the IPN
  59. IPN detection and localization of Cygnus X-1 flares
  60. RXTE Observations of SGR 1900+14
  61. SGR1900+14 activity
  62. IPN/HETE Detection of Bursts from SGR1900+14
  63. IPN detection of further activity from SGR1806-20
  64. Optical observation of SGR 1806-20 at the 6-m SAO telescope
  65. Probable SGR or Short Duration GRB Detected by HETE
  66. Dramatic Increase in the Rate of X-ray Bursts Reported by HETE
  67. Possible burst from SGR1806-20
  68. IPN detection of SGR1900+14
  69. X-ray precursors to the large flare from SGR 1900+14
  70. SGR 1900+14: No evidence of extended X-ray emission
  71. SGR 1900+14 : RXTE observations
  72. BeppoSAX/NFI Follow-up Observation of SGR 1900+14
  73. SGR1900+14
  74. SGR 1900+14: Correction to GCN 1049
  75. Millimeter observation of SGR 1900+14
  76. SGR 1900+14: Detection of extended X-ray emission
  77. Chandra Observations of SGR 1900+14
  78. SGR 1900+14, Chandra observations
  79. Chandra Observations of SGR 1900+14
  80. SGR1900+14, I-band observations
  81. SGR 1806-20 burst activity
  82. BATSE GRB trigger criteria
  83. X-ray/GRB 1SAX J0835.9+5118, BATSE Observation
  84. GRB990308 not a new SGR
  85. GRB990308, Possible new SGR~0209+70
  86. SGR1900+14, BeppoSAX-GRBM observations
  87. SGR1627-41
  88. SGR1627-41, RXTE/ASM observations
  89. Reduced error box of SGR 1627-41
  90. SGR 1627-41
  91. Discovery of a new SGR source, SGR1627-41
  92. SGR 1900+14
  93. SGR1900+14
  94. SGR1900+14
  95. BATSE on-board GRB trigger change
  96. IRAS 18119-1342 and the possible new SGR
  97. Possible new SGR from US Naval Observatory
  98. RXTE Observations of SGR 1814-13

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