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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').
Advanced Search

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.

Advanced Search Examples (click to copy):

subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

45713 results found.

  1. Swift/BAT possible detection of a weak burst GRB050430
  2. GRB 050401: Rc observation
  3. GRB050416a: Radio Detection
  4. GRB 050422: Swift-UVOT observation
  5. GRB 050422: Swift-BAT refined analysis
  6. GRB 050422: Swift XRT Position
  7. Swift Detection of GRB 050422
  8. GRB 050421: NIR observations
  9. GRB 050416: Optical/NIR observations
  10. GRB 050421: SLOTIS observations
  11. GRB 050421: Further Analysis of IR imaging
  12. GRB050421: Radio Observations
  13. GRB050421: Radio Observations
  14. GRB 050421: Swift-UVOT observation
  15. GRB 050421: IR Observations
  16. GRB 050421: Swift-BAT refined analysis
  17. GRB 050421: ROTSE-III Optical Limits
  18. GRB 050421: NIR observations re-examination
  19. GRB050421
  20. GRB 050421: early Swift XRT analysis results
  21. GRB 050421: NIR observations
  22. GRB050421: P60 Observations
  23. GRB 050421: BOOTES-2 simultaneous optical observations
  24. GRB 050421: Optical observations at the INT
  25. Swift Detection of GRB050421
  26. GRB 050416b: Tentative Swift XRT Position
  27. GRB 050315: potential host galaxy
  28. GRB050326: analysis of the XMM-Newton observation
  29. GRB050418: Null Optical Observations
  30. GRB 050412: Chandra observations
  31. GRB050416A, optical observations
  32. GRB 050418: Swift-BAT refined analysis
  33. Swift-BAT detection of the bright and long GRB 050418
  34. GRB 050416: Mitsume optical observation
  35. GRB 050416 : optical observation at Xinglong observatory
  36. GRB 050416B: optical observations
  37. GRB 050416b: Swift-BAT refined analysis
  38. GRB 050416b: LCO observations
  39. GRB 050416b: LCO observations
  40. GRB050416B: IR observations
  41. GRB 050416: Swift/UVOT refined analysis
  42. Swift-BAT detection of GRB 050416b
  43. IBAS GRB Alert # 2463: not a GRB
  44. GRB050412: Radio Observations
  45. GRB 050416: Swift/UVOT detection of afterglow emission
  46. GRB050416: Refined Swift-XRT analysis
  47. GRB050416: Maidanak optical observations
  48. GRB 050416: Swift-BAT refined analysis
  49. GRB 050416: ART observations
  50. GRB 050416,optical observation
  51. GRB 050416: KAIT observations
  52. GRB050416: P200 NIR Observations
  53. GRB 050416: Swift XRT Position
  54. GRB 050416: Radio observations
  55. Confirmation of OT for GRB050416
  56. GRB050416: P60 Afterglow Candidate
  57. Swift BAT/XRT Detection of GRB 050416
  58. GRB 050412: Subaru observations
  59. GRB 050408: RTT150 optical observations
  60. GRB050408: optical observation
  61. GRB 050412: PROMPT VRcIc Observations
  62. GRB 050408: Kuiper 1.5m observations
  63. GRB 050412: optical limit
  64. GRB 050412: optical observations
  65. GRB 050408: refined XRT analysis, no jet break seen yet
  66. GRB 050412: early Swift XRT analysis results
  67. GRB 050412 : XingLong optical observation
  68. GRB 050412: Swift-BAT refined analysis
  69. GRB 050412: ANU 2.3m observations
  70. GRB 050412: Early Optical/Ultraviolet Observations with
  71. GRB 050412: retraction of UVOT transient report
  72. GRB 050412: UVOT transient not in XRT error circle
  73. GRB 050408: SDSS Field Calibration
  74. GRB 050412: Optical limit
  75. GRB 050412: LCO Optical Observations
  76. GRB 050412: Optical observations
  77. GRB050412: P60 Observations
  78. GRB 050412: Swift XRT Position
  79. GRB050412: optical limit before and during GRB
  80. GRB 050412: LCO optical observations
  81. GRB050412: ROTSE-III Optical Limits
  82. Swift-BAT Detection of GRB 050412: A Bright, Long Burst
  83. GRB 050412: IR and Optical observations
  84. GRB 050412: IR Observations
  85. GRB050408: Radio Observations
  86. GRB 050401: Optical limit
  87. GRB 050408: Optical limit
  88. GRB050410: P60 Observations
  89. GRB 050410: Early Optical/Ultraviolet Observations with Swift/UVOT
  90. GRB 050410, optical observations
  91. GRB 050408: PROMPT VRcIc Observations
  92. GRB 050408: Early Optical/Ultraviolet Observations with Swift/UVOT
  93. GRB 050410 R band Optical Observations
  94. GRB050410 : Null detection report
  95. GRB 050410, optical observations
  96. GRB050410: Radio Observations
  97. GRB 050408: Swift XRT measurement of possible jet break
  98. GRB050410: MASTER optical observations
  99. GRB 050410: Early observations with Swift-UVOT
  100. Swift-BAT detection of GRB 050410

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