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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"

35954 results found.

  1. IPN triangulation of GRB031020 (large error box)
  2. IPN triangulation of GRB031016 (two large error boxes)
  3. IBAS alert 1180 refers to a burst from SGR 1806-20
  4. HETE Prompt GRB Light Curves and Color-Color Diagrams
  5. IPN triangulation of GRB031014 (annulus)
  6. SGR1806-20 bursts on 031008. Helicon detection and small error box.
  7. IPN triangulation of GRB031008 (annulus)
  8. IPN detection of continued activity from SGR1806-20
  9. IPN triangulation of GRB031007 (two large error boxes)
  10. XRF 030723: Subaru Optical Observations
  11. IPN triangulation of GRB031004B (annulus)
  12. IPN triangulation of GRB031004A (short/hard; annulus)
  13. IPN triangulation of GRB030929 (short/hard; annulus)
  14. XRF 030824: Early follow-up observation at Kiso observatory
  15. XRF 030824: observations at CFHT
  16. IPN triangulation of GRB030926 (short/hard; large error box)
  17. IPN triangulation of GRB030922B (large error box)
  18. IPN triangulation of GRB030922A (large error box)
  19. IPN triangulation of GRB030921 (large error box)
  20. IPN triangulation of GRB030919 (large error box)
  21. GRB030922 triangulation (annulus)
  22. GRB030913: Subaru Optical Observations
  23. GRB 030913: ROTSE-3c Optical Observations
  24. GRB030913: OT's limit by MASTER
  25. GRB030921 triangulation (annulus)
  26. GRB030913, candidate afterglow observations
  27. GRB 030913, optical candidate
  28. GRB 030913, BOOTES observations
  29. IPN triangulation of GRB030916 (possible short/hard GRB; large error box)
  30. GRB030913 (=H2849): TAROT Observations
  31. GRB030913: wide field imaging (7 sq.deg) of the error box by MASTER
  32. Magellan Observations of GRB030725 (=H2779)
  33. GRB030913 (=H2849): A GRB Possibly Localized by HETE
  34. IPN triangulation of GRB030908 (annulus)
  35. GRB 030913: Optical limit at RIKEN
  36. XRF030824: Optical observations
  37. IPN triangulation of GRB030903 (large error box)
  38. IPN triangulation of GRB030831 (annulus)
  39. IPN triangulation of GRB030830 (large error box)
  40. GRB 030824: Candidate Follow-Up
  41. IPN triangulation of GRB030827 (large error box)
  42. GRB 030823 observation at Ouda
  43. XRF030824: Second-epoch Palomar observations
  44. IPN triangulation of GRB030822 (annulus)
  45. GRB030823: Palomar observations
  46. XRF030824: Palomar observations
  47. GRB 030824: Candidate Afterglow (or Variable/Flare Star?)
  48. IPN triangulation of GRB030821 (=H2814; refined error box)
  49. GRB 030821(=H2814): A Faint, Long GRB Localized by the HETE WXM and the IPN
  50. Summary of recent IPN and HETE detections of SGR bursts
  51. IPN triangulation of GRB030814 (annulus)
  52. IPN detection of continued activity from SGR1806-20
  53. 030813 SGR event (Konus-Wind observation)
  54. GRB 030817 = H2808 TAROT optical observations
  55. SGR 1808-20 (=H2802): A Possible new SGR
  56. GRB 021206 Optical Observations
  57. IPN triangulation of GRB030808 (two large error boxes)
  58. IPN triangulation of GRB030806 (large burst; large error box)
  59. XRF030723(=H2777): Chandra Fading X-ray Afterglow Confirmed
  60. IPN/HETE summary of recent bursts from SGR1806-20
  61. XRF 030723: Detection of a rebrightening in the optical afterglow
  62. GRB030725: Optical observations
  63. XRF030723, BVRcIc field photometry update
  64. IPN triangulation of GRB030801 (large error box)
  65. GRB021206 optical counterpart upper limit
  66. IPN triangulation of GRB030731 (annulus)
  67. IBAS GRB Alerts 1011-1017 NOT CONFIRMED
  68. IPN triangulation of GRB030725 (=H2779; small error box)
  69. XRF030723 (=H2777): Second Epoch Magellan Observations
  70. GRB 030725: optical observations.
  71. GRB030725, optical transient observations
  72. IPN triangulation of GRB030726 (large error box)
  73. IPN triangulation of GRB030722 (large error box)
  74. IPN triangulation of GRB030721 (large error box)
  75. XRF030723 Radio Observations
  76. XRF030723(=H2777): Chandra Observations
  77. Magellan Observations of XRF030723 (=H2777)
  78. GRB030723: Upper limits from historical observations
  79. GRB030725, possible optical transient
  80. XRF030723: Palomar observations and proposed counterpart
  81. GRB030725 (=H2779): A Bright GRB Localized by HETE
  82. XRF030723: optical observations
  83. XRF030723 (= H2777): Chandra Observations Scheduled
  84. XRF030723, BVRcIc field photometry
  85. XRF030723, optical observations
  86. GRB030723, optical observations
  87. IBAS GRB Alerts 969 970
  88. IPN triangulation of GRB030717 (annulus)
  89. GRB030329: Subaru Optical Spectroscopy
  90. Triangulation of GRB030715 (single large error box)
  91. Triangulation of GRB030714 (single large error box)
  92. 030716 NOT a GRB
  93. IPN triangulation of GRB030714 (two large error boxes)
  94. IPN triangulation of GRB030715 (two large error boxes)
  95. GRB030329: RTT150 optical observations
  96. GRBlog: Compilation of all GCN Circ. data
  97. IPN detection of renewed activity from SGR1806-20
  98. IPN triangulation of GRB030711 (annulus, =SGR0525-66?)
  99. IPN triangulation of GRB030710 (annulus)
  100. IPN triangulation of GRB030709 (annulus)

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