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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"

19544 results found.

  1. SGR 1806-20, RHESSI observations of the 041227 giant flare
  2. Third epoch observations of SGR 1806-20 with VLA
  3. Second Epoch VLA observations of SGR 1806-20
  4. Second-epoch VLA observations of SGR 1806-20
  5. SGR1806: Detection of a Sudden Ionospheric Disturbance
  6. DETECTION OF POLARIZATION OF THE RADIO EMISSION FROM SGR 1806-20
  7. VLA observations of SGR 1806-20
  8. SGR1806 VLA Observations
  9. VLA observations of SGR 1806-20
  10. SGR1806-20: RXTE-PCA observation of the 041227 super-flare
  11. GRB 041217: Optical observations
  12. SGR1806-20: Swift-BAT observation of the 041227 super-flare
  13. Detection of the SGR 1806-20 giant outburst back-scattered by the
  14. The giant outburst from SGR 1806-20
  15. Giant flare from SGR 1806-20 detected by INTEGRAL
  16. GRB041228: ROTSE-III Optical Observations
  17. GRB041228: Swift-BAT detection of a burst
  18. GRB041219; RXTE ASM Observations
  19. NIR Observations of GRB 041219
  20. GRB041226: ROTSE-III Optical Observations
  21. GRB041226: Swift-BAT detection of a burst
  22. GRB041223: decay of the afterglow
  23. GRB041224: ROTSE-III Optical Observations
  24. GRB 041223: XRT afterglow spectrum and light curve
  25. GRB 041223 Fluence measured by Swift-BAT
  26. GRB041224: Swift-BAT detection of a soft burst
  27. GRB041223: optical and NIR observations with REM
  28. Swift-BAT Time History of GRB041219
  29. GRB041223: Swift XRT Detection of X-ray Afterglow Emission
  30. GRB041223: ROTSE-III Optical Observations
  31. GRB041223: Swift-BAT detection of a bright long burst
  32. Very high activity of SGR 1806-20
  33. GRB041220: Swift-BAT burst
  34. GRB 041219 Optical Observations
  35. GRB041219c: Third Burst in One Day from Swift-BAT
  36. GRB041219b: A Swift-BAT burst
  37. Swift-BAT detection of the bright long burst GRB041219
  38. GRB041217: optical limit 30 min after GRB
  39. GRB041217: Optical Observations
  40. GRB041217: NIR and optical observations with REM
  41. GRB041217: P60 Optical Observations
  42. GRB041217: Infrared Observations
  43. GRB041217: The First GRB Located On-Board Swift
  44. Summary of the recent bursts from SGR 1806-20
  45. IBAS GRB Alert # 2034
  46. Bright bursts from SGR1806-20
  47. Konus-Wind observation of a series SGR 1806-20 bursts on 041005
  48. Bursts from SGR 1806-20: Preliminary INTEGRAL results
  49. Very strong outburst from SGR 1806-20 detected with INTEGRAL
  50. SGR 1806-20 still active
  51. GRB040916: Optical observations
  52. An intense burst from SGR1806-20
  53. Very bright burst detected from SGR 1806-20
  54. Increase of SGR 1806-20 activity
  55. Bursting activity from SGR 1806-20 detected with IBAS
  56. Ongoing activity of SGR 1806-20
  57. GRB040706:observation at University of Miyazaki
  58. SGR 1806-20: no IR variability of the proposed counterparts
  59. SGR 1806-20, potential NIR counterpart
  60. Activivty of SGR 1806-20
  61. IBAS GRB Alerts n.1785 to 1791
  62. GRB040422: optical and NIR observations at the VLT
  63. Summary of recent bursts from SGR 1806-20 detected by INTEGRAL
  64. IBAS GRB Alert 1694
  65. IBAS GRB alerts 1679, 1680, 1681
  66. GRB040223, improved XMM position
  67. IBAS results on a burst from SGR1806-20
  68. SN 2003jd (SN/GRB?) - possible association with GRB 030929
  69. IBAS alert 1180 refers to a burst from SGR 1806-20
  70. Ongoing Bursting Activity from SGR 1806-20 detected with IBAS
  71. SGR1806-20 bursts on 031008. Helicon detection and small error box.
  72. SGR 1806-20 bursts with INTEGRAL and IBAS announcement on Soft Gamma-Ray Repeaters
  73. A burst from SGR 1806-20 detected with IBAS
  74. IPN triangulation of GRB030926 (short/hard; large error box)
  75. IBAS detection of bursts from SGR 1806-20
  76. Radio Observations of SGR1806-20
  77. INTEGRAL ToO OBSERVATIONS OF SGR1806-20: CALL FOR CORRELATED OBSERVATIONS
  78. Summary of recent IPN and HETE detections of SGR bursts
  79. Clarification of GCN 2354 on SGR1806-20
  80. IPN detection of continued activity from SGR1806-20
  81. 030813 SGR event (Konus-Wind observation)
  82. SGR 1808-20 (=H2802): A Possible new SGR
  83. SGR 1806-20, submm observations
  84. RXTE PCA Observations of SGR1806-20 Region
  85. HETE detection of burst from SGR1806-20
  86. GRB030329 observed as a sudden ionospheric disturbance (SID)
  87. IPN triangulation of GRB021219
  88. IPN detection of continued activity from SGR1806-20
  89. IPN detection of renewed activity from SGR1806-20
  90. IPN detection of continued SGR1900+14 activity
  91. IPN confirmation of the reactivation of SGR1900+14
  92. IPN detection of possible reactivation of SGR1900+14
  93. IPN triangulation of bursts from SGR1900+14, November 1-2, 2002
  94. SGR1900+14 activity, November 2-4, 2002
  95. Detection of activity from SGR 1900+14 with the RXTE/PCA
  96. IPN detection of a burst from SGR1900+14
  97. Gemini IR Detection of AXP 1E 2259+586 Post-Burst
  98. SGR-like X-ray Bursts from AXP 1E 2259+586: follow-up
  99. AXP 1E2259+586: quasi-simultaneous optical observation
  100. AXP 1E2259+586 optical observations

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