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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"

28048 results found.

  1. GRB 050422: Swift-BAT refined analysis
  2. Swift Detection of GRB 050422
  3. GRB 050421: SLOTIS observations
  4. GRB 050421: Further Analysis of IR imaging
  5. GRB050421: Radio Observations
  6. GRB050421: Radio Observations
  7. GRB 050421: IR Observations
  8. GRB 050421: Swift-BAT refined analysis
  9. GRB050421
  10. GRB 050421: early Swift XRT analysis results
  11. GRB 050421: NIR observations
  12. GRB050421: P60 Observations
  13. GRB 050421: BOOTES-2 simultaneous optical observations
  14. GRB 050416b: Tentative Swift XRT Position
  15. GRB 050315: potential host galaxy
  16. GRB050326: analysis of the XMM-Newton observation
  17. GRB050418: Null Optical Observations
  18. GRB050416A, optical observations
  19. GRB 050418: Swift-BAT refined analysis
  20. GRB 050416: Mitsume optical observation
  21. GRB050416B: IR observations
  22. GRB050412: Radio Observations
  23. GRB 050416: Swift/UVOT detection of afterglow emission
  24. GRB050416: Refined Swift-XRT analysis
  25. GRB 050416,optical observation
  26. GRB050416: P200 NIR Observations
  27. GRB 050416: Radio observations
  28. Swift BAT/XRT Detection of GRB 050416
  29. GRB 050412: PROMPT VRcIc Observations
  30. GRB 050408: Kuiper 1.5m observations
  31. GRB 050412: early Swift XRT analysis results
  32. GRB 050412: Early Optical/Ultraviolet Observations with
  33. GRB 050408: SDSS Field Calibration
  34. GRB050412: P60 Observations
  35. GRB 050412: Swift XRT Position
  36. Swift-BAT Detection of GRB 050412: A Bright, Long Burst
  37. GRB 050412: IR and Optical observations
  38. GRB 050412: IR Observations
  39. GRB050408: Radio Observations
  40. GRB 050401: Optical limit
  41. GRB050410: P60 Observations
  42. GRB 050410: Early Optical/Ultraviolet Observations with Swift/UVOT
  43. GRB 050408: Early Optical/Ultraviolet Observations with Swift/UVOT
  44. GRB050410: Radio Observations
  45. GRB050410: MASTER optical observations
  46. GRB 050410: Early observations with Swift-UVOT
  47. Swift-BAT detection of GRB 050410
  48. GRB 050408: Inconsistency of host galaxy identification
  49. GRB 050408: Subaru Observations
  50. GRB 050408: WIDGET simultaneous optical observations
  51. GRB 050408: Properties of the Host Galaxy
  52. GRB050408: Radio Observations
  53. GRB 050408: Swift XRT analysis
  54. GRB 050408: Optical limit at 20 min after the burst
  55. GRB050408: REM NIR and Optical observation
  56. GRB 050408,optical observation
  57. GRB 050408: Mercator Optical Observations
  58. GRB 050408: Optical afterglow confirmed
  59. GRB 050408: opitcal observation
  60. GRB 050408, optical observations
  61. GRB 050408 optical candidate
  62. GRB 050408: Swift XRT Position
  63. GRB050408: MASTER optical observations
  64. GRB050401: Radio Detection
  65. GRB 050406: early Swift XRT analysis results
  66. GRB 050406 BAT refined analysis
  67. GRB 050406: Early observations with Swift-UVOT
  68. Swift-BAT detection of GRB 050406
  69. GRB050401, radio observation at 4.8 GHz and 8.64 GHz
  70. GRB 050401: VLT spectroscopic redshift
  71. GRB 050401 BAT refined analysis
  72. GRB050401: TNG R-band observation
  73. GRB 050402: Early observations with Swift-UVOT
  74. Swift Trigger 113225: P60 Observations
  75. GRB 050401: Optical afterglow confirmed
  76. GRB 050401: Prompt XRT position
  77. Retraction of three Swift GRB triggers
  78. GRB050331: No Afterglow Detected
  79. Swift-BAT detection of GRB 050331b
  80. GRB 050331: Swift UVOT Source
  81. Swift-BAT detection of GRB 050331
  82. GRB 050326: Early observations with Swift-UVOT
  83. GRB 050326 XMM-Newton observation
  84. GRB 050326: Swift XRT Position
  85. GRB 050326 BAT refined analysis
  86. GRB050326: delayed XRT observation
  87. GRB050319, color indices
  88. GRB050319: optical observation, March 20-22
  89. GRB050319: RTT150 Optical Observations
  90. Swift-BAT trigger 112060 is not a real GRB
  91. GRB 050318: Swift-BAT refined analysis
  92. GRB050319: VLA Observations
  93. GRB050319: radio observation
  94. GRB 050319: Swift-UVOT detection of the afterglow
  95. GRB 050315: Variability Analysis of Swift BAT Time History
  96. GRB050319: Radio Observations
  97. GRB 050319: NIR afterglow candidate
  98. GRB 050319:Near IR afterglow
  99. GRB 050318: SWIFT-UVOT refined analysis
  100. GRB 050319 : Confirmation of optical afterglow decay

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