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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"

19941 results found.

  1. Second-epoch VLA observations of SGR 1806-20
  2. SGR1806: Detection of a Sudden Ionospheric Disturbance
  3. DETECTION OF POLARIZATION OF THE RADIO EMISSION FROM SGR 1806-20
  4. VLA observations of SGR 1806-20
  5. SGR1806 VLA Observations
  6. VLA observations of SGR 1806-20
  7. SGR1806-20: RXTE-PCA observation of the 041227 super-flare
  8. GRB 041217: Optical observations
  9. SGR1806-20: Swift-BAT observation of the 041227 super-flare
  10. Detection of the SGR 1806-20 giant outburst back-scattered by the
  11. The giant outburst from SGR 1806-20
  12. Giant flare from SGR 1806-20 detected by INTEGRAL
  13. GRB041228: ROTSE-III Optical Observations
  14. GRB041228: Swift-BAT detection of a burst
  15. GRB041219; RXTE ASM Observations
  16. NIR Observations of GRB 041219
  17. GRB041226: ROTSE-III Optical Observations
  18. GRB041226: Swift-BAT detection of a burst
  19. GRB041223: decay of the afterglow
  20. GRB041224: ROTSE-III Optical Observations
  21. GRB 041223: XRT afterglow spectrum and light curve
  22. GRB 041223 Fluence measured by Swift-BAT
  23. GRB041224: Swift-BAT detection of a soft burst
  24. GRB041223: optical and NIR observations with REM
  25. Swift-BAT Time History of GRB041219
  26. GRB041223: Swift XRT Detection of X-ray Afterglow Emission
  27. GRB041223: ROTSE-III Optical Observations
  28. GRB041223: Swift-BAT detection of a bright long burst
  29. Very high activity of SGR 1806-20
  30. GRB041220: Swift-BAT burst
  31. GRB 041219 Optical Observations
  32. GRB041219c: Third Burst in One Day from Swift-BAT
  33. GRB041219b: A Swift-BAT burst
  34. Swift-BAT detection of the bright long burst GRB041219
  35. GRB041217: optical limit 30 min after GRB
  36. GRB041217: Optical Observations
  37. GRB041217: NIR and optical observations with REM
  38. GRB041217: P60 Optical Observations
  39. GRB041217: Infrared Observations
  40. GRB041217: The First GRB Located On-Board Swift
  41. Summary of the recent bursts from SGR 1806-20
  42. IBAS GRB Alert # 2034
  43. Bright bursts from SGR1806-20
  44. Konus-Wind observation of a series SGR 1806-20 bursts on 041005
  45. Bursts from SGR 1806-20: Preliminary INTEGRAL results
  46. Very strong outburst from SGR 1806-20 detected with INTEGRAL
  47. SGR 1806-20 still active
  48. GRB040916: Optical observations
  49. An intense burst from SGR1806-20
  50. Very bright burst detected from SGR 1806-20
  51. Increase of SGR 1806-20 activity
  52. Bursting activity from SGR 1806-20 detected with IBAS
  53. Ongoing activity of SGR 1806-20
  54. GRB040706:observation at University of Miyazaki
  55. SGR 1806-20: no IR variability of the proposed counterparts
  56. SGR 1806-20, potential NIR counterpart
  57. Activivty of SGR 1806-20
  58. IBAS GRB Alerts n.1785 to 1791
  59. GRB040422: optical and NIR observations at the VLT
  60. Summary of recent bursts from SGR 1806-20 detected by INTEGRAL
  61. IBAS GRB Alert 1694
  62. IBAS GRB alerts 1679, 1680, 1681
  63. GRB040223, improved XMM position
  64. IBAS results on a burst from SGR1806-20
  65. SN 2003jd (SN/GRB?) - possible association with GRB 030929
  66. IBAS alert 1180 refers to a burst from SGR 1806-20
  67. Ongoing Bursting Activity from SGR 1806-20 detected with IBAS
  68. SGR1806-20 bursts on 031008. Helicon detection and small error box.
  69. SGR 1806-20 bursts with INTEGRAL and IBAS announcement on Soft Gamma-Ray Repeaters
  70. A burst from SGR 1806-20 detected with IBAS
  71. IPN triangulation of GRB030926 (short/hard; large error box)
  72. IBAS detection of bursts from SGR 1806-20
  73. Radio Observations of SGR1806-20
  74. INTEGRAL ToO OBSERVATIONS OF SGR1806-20: CALL FOR CORRELATED OBSERVATIONS
  75. Summary of recent IPN and HETE detections of SGR bursts
  76. Clarification of GCN 2354 on SGR1806-20
  77. IPN detection of continued activity from SGR1806-20
  78. 030813 SGR event (Konus-Wind observation)
  79. SGR 1808-20 (=H2802): A Possible new SGR
  80. SGR 1806-20, submm observations
  81. RXTE PCA Observations of SGR1806-20 Region
  82. HETE detection of burst from SGR1806-20
  83. GRB030329 observed as a sudden ionospheric disturbance (SID)
  84. IPN triangulation of GRB021219
  85. IPN detection of continued activity from SGR1806-20
  86. IPN detection of renewed activity from SGR1806-20
  87. IPN detection of continued SGR1900+14 activity
  88. IPN confirmation of the reactivation of SGR1900+14
  89. IPN detection of possible reactivation of SGR1900+14
  90. IPN triangulation of bursts from SGR1900+14, November 1-2, 2002
  91. SGR1900+14 activity, November 2-4, 2002
  92. Detection of activity from SGR 1900+14 with the RXTE/PCA
  93. IPN detection of a burst from SGR1900+14
  94. Gemini IR Detection of AXP 1E 2259+586 Post-Burst
  95. SGR-like X-ray Bursts from AXP 1E 2259+586: follow-up
  96. AXP 1E2259+586: quasi-simultaneous optical observation
  97. AXP 1E2259+586 optical observations
  98. SGR-like Bursts from the AXP 1E 2259+586
  99. IPN detection of possible bursts from SGR1806-20
  100. XRF 020427: Sudden Ionospheric Disturbance (SID)

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