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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"

28047 results found.

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

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