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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"

615 results found.

  1. ATCA observations of SGR 1806-20
  2. SGR 1806-20, RHESSI observations of the 041227 giant flare
  3. Third epoch observations of SGR 1806-20 with VLA
  4. Second Epoch VLA observations of SGR 1806-20
  5. Second-epoch VLA observations of SGR 1806-20
  6. SGR1806: Detection of a Sudden Ionospheric Disturbance
  7. DETECTION OF POLARIZATION OF THE RADIO EMISSION FROM SGR 1806-20
  8. VLA observations of SGR 1806-20
  9. SGR1806 VLA Observations
  10. VLA observations of SGR 1806-20
  11. SGR1806-20: RXTE-PCA observation of the 041227 super-flare
  12. Detection of the SGR 1806-20 giant outburst back-scattered by the
  13. The giant outburst from SGR 1806-20
  14. Giant flare from SGR 1806-20 detected by INTEGRAL
  15. Very high activity of SGR 1806-20
  16. Summary of the recent bursts from SGR 1806-20
  17. IBAS GRB Alert # 2034
  18. Bright bursts from SGR1806-20
  19. Konus-Wind observation of a series SGR 1806-20 bursts on 041005
  20. Bursts from SGR 1806-20: Preliminary INTEGRAL results
  21. Very strong outburst from SGR 1806-20 detected with INTEGRAL
  22. SGR 1806-20 still active
  23. An intense burst from SGR1806-20
  24. Very bright burst detected from SGR 1806-20
  25. Increase of SGR 1806-20 activity
  26. Bursting activity from SGR 1806-20 detected with IBAS
  27. Ongoing activity of SGR 1806-20
  28. GRB040706:observation at University of Miyazaki
  29. SGR 1806-20: no IR variability of the proposed counterparts
  30. SGR 1806-20, potential NIR counterpart
  31. Activivty of SGR 1806-20
  32. IBAS GRB Alerts n.1785 to 1791
  33. Summary of recent bursts from SGR 1806-20 detected by INTEGRAL
  34. IBAS GRB Alert 1694
  35. IBAS GRB alerts 1679, 1680, 1681
  36. IBAS results on a burst from SGR1806-20
  37. IBAS alert 1180 refers to a burst from SGR 1806-20
  38. Ongoing Bursting Activity from SGR 1806-20 detected with IBAS
  39. SGR1806-20 bursts on 031008. Helicon detection and small error box.
  40. SGR 1806-20 bursts with INTEGRAL and IBAS announcement on Soft Gamma-Ray Repeaters
  41. A burst from SGR 1806-20 detected with IBAS
  42. IPN triangulation of GRB030926 (short/hard; large error box)
  43. IBAS detection of bursts from SGR 1806-20
  44. Radio Observations of SGR1806-20
  45. INTEGRAL ToO OBSERVATIONS OF SGR1806-20: CALL FOR CORRELATED OBSERVATIONS
  46. Summary of recent IPN and HETE detections of SGR bursts
  47. Clarification of GCN 2354 on SGR1806-20
  48. IPN detection of continued activity from SGR1806-20
  49. 030813 SGR event (Konus-Wind observation)
  50. SGR 1808-20 (=H2802): A Possible new SGR
  51. SGR 1806-20, submm observations
  52. RXTE PCA Observations of SGR1806-20 Region
  53. HETE detection of burst from SGR1806-20
  54. GRB030329 observed as a sudden ionospheric disturbance (SID)
  55. IPN triangulation of GRB021219
  56. IPN detection of continued activity from SGR1806-20
  57. IPN detection of renewed activity from SGR1806-20
  58. IPN detection of continued SGR1900+14 activity
  59. IPN confirmation of the reactivation of SGR1900+14
  60. IPN detection of possible reactivation of SGR1900+14
  61. IPN triangulation of bursts from SGR1900+14, November 1-2, 2002
  62. SGR1900+14 activity, November 2-4, 2002
  63. Detection of activity from SGR 1900+14 with the RXTE/PCA
  64. GRB 021008, optical observations
  65. IPN triangulation of GRB021008 (single error box)
  66. IPN triangulation of GRB021008 (two small error boxes)
  67. IPN detection of a burst from SGR1900+14
  68. Gemini IR Detection of AXP 1E 2259+586 Post-Burst
  69. SGR-like X-ray Bursts from AXP 1E 2259+586: follow-up
  70. AXP 1E2259+586: quasi-simultaneous optical observation
  71. AXP 1E2259+586 optical observations
  72. SGR-like Bursts from the AXP 1E 2259+586
  73. IPN detection of possible bursts from SGR1806-20
  74. XRF 020427: Sudden Ionospheric Disturbance (SID)
  75. Mars Odyssey joins the IPN
  76. IPN detection and localization of Cygnus X-1 flares
  77. RXTE Observations of SGR 1900+14
  78. SGR1900+14 activity
  79. IPN/HETE Detection of Bursts from SGR1900+14
  80. IPN detection of further activity from SGR1806-20
  81. Optical observation of SGR 1806-20 at the 6-m SAO telescope
  82. Probable SGR or Short Duration GRB Detected by HETE
  83. Dramatic Increase in the Rate of X-ray Bursts Reported by HETE
  84. Possible burst from SGR1806-20
  85. IPN detection of SGR1900+14
  86. X-ray precursors to the large flare from SGR 1900+14
  87. SGR 1900+14: No evidence of extended X-ray emission
  88. SGR 1900+14 : RXTE observations
  89. BeppoSAX/NFI Follow-up Observation of SGR 1900+14
  90. SGR1900+14
  91. SGR 1900+14: Correction to GCN 1049
  92. Millimeter observation of SGR 1900+14
  93. SGR 1900+14: Detection of extended X-ray emission
  94. Chandra Observations of SGR 1900+14
  95. SGR 1900+14, Chandra observations
  96. Chandra Observations of SGR 1900+14
  97. SGR1900+14, I-band observations
  98. SGR 1806-20 burst activity
  99. BATSE GRB trigger criteria
  100. X-ray/GRB 1SAX J0835.9+5118, BATSE Observation

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