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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"

26339 results found.

  1. GRB 050421: early Swift XRT analysis results
  2. GRB 050421: NIR observations
  3. GRB050421: P60 Observations
  4. GRB 050421: BOOTES-2 simultaneous optical observations
  5. GRB 050416b: Tentative Swift XRT Position
  6. GRB 050315: potential host galaxy
  7. GRB050326: analysis of the XMM-Newton observation
  8. GRB050418: Null Optical Observations
  9. GRB050416A, optical observations
  10. GRB 050418: Swift-BAT refined analysis
  11. GRB 050416: Mitsume optical observation
  12. GRB050416B: IR observations
  13. GRB050412: Radio Observations
  14. GRB 050416: Swift/UVOT detection of afterglow emission
  15. GRB050416: Refined Swift-XRT analysis
  16. GRB 050416,optical observation
  17. GRB050416: P200 NIR Observations
  18. GRB 050416: Radio observations
  19. Swift BAT/XRT Detection of GRB 050416
  20. GRB 050412: PROMPT VRcIc Observations
  21. GRB 050408: Kuiper 1.5m observations
  22. GRB 050412: early Swift XRT analysis results
  23. GRB 050412: Early Optical/Ultraviolet Observations with
  24. GRB 050408: SDSS Field Calibration
  25. GRB050412: P60 Observations
  26. GRB 050412: Swift XRT Position
  27. Swift-BAT Detection of GRB 050412: A Bright, Long Burst
  28. GRB 050412: IR and Optical observations
  29. GRB 050412: IR Observations
  30. GRB050408: Radio Observations
  31. GRB 050401: Optical limit
  32. GRB050410: P60 Observations
  33. GRB 050410: Early Optical/Ultraviolet Observations with Swift/UVOT
  34. GRB 050408: Early Optical/Ultraviolet Observations with Swift/UVOT
  35. GRB050410: Radio Observations
  36. GRB050410: MASTER optical observations
  37. GRB 050410: Early observations with Swift-UVOT
  38. Swift-BAT detection of GRB 050410
  39. GRB 050408: Inconsistency of host galaxy identification
  40. GRB 050408: Subaru Observations
  41. GRB 050408: WIDGET simultaneous optical observations
  42. GRB 050408: Properties of the Host Galaxy
  43. GRB050408: Radio Observations
  44. GRB 050408: Swift XRT analysis
  45. GRB 050408: Optical limit at 20 min after the burst
  46. GRB050408: REM NIR and Optical observation
  47. GRB 050408,optical observation
  48. GRB 050408: Mercator Optical Observations
  49. GRB 050408: Optical afterglow confirmed
  50. GRB 050408: opitcal observation
  51. GRB 050408, optical observations
  52. GRB 050408 optical candidate
  53. GRB 050408: Swift XRT Position
  54. GRB050408: MASTER optical observations
  55. GRB050401: Radio Detection
  56. GRB 050406: early Swift XRT analysis results
  57. GRB 050406 BAT refined analysis
  58. GRB 050406: Early observations with Swift-UVOT
  59. Swift-BAT detection of GRB 050406
  60. GRB050401, radio observation at 4.8 GHz and 8.64 GHz
  61. GRB 050401: VLT spectroscopic redshift
  62. GRB 050401 BAT refined analysis
  63. GRB050401: TNG R-band observation
  64. GRB 050402: Early observations with Swift-UVOT
  65. Swift Trigger 113225: P60 Observations
  66. GRB 050401: Optical afterglow confirmed
  67. GRB 050401: Prompt XRT position
  68. Retraction of three Swift GRB triggers
  69. GRB050331: No Afterglow Detected
  70. Swift-BAT detection of GRB 050331b
  71. GRB 050331: Swift UVOT Source
  72. Swift-BAT detection of GRB 050331
  73. GRB 050326: Early observations with Swift-UVOT
  74. GRB 050326 XMM-Newton observation
  75. GRB 050326: Swift XRT Position
  76. GRB 050326 BAT refined analysis
  77. GRB050326: delayed XRT observation
  78. GRB050319, color indices
  79. GRB050319: optical observation, March 20-22
  80. GRB050319: RTT150 Optical Observations
  81. Swift-BAT trigger 112060 is not a real GRB
  82. GRB 050318: Swift-BAT refined analysis
  83. GRB050319: VLA Observations
  84. GRB050319: radio observation
  85. GRB 050319: Swift-UVOT detection of the afterglow
  86. GRB 050315: Variability Analysis of Swift BAT Time History
  87. GRB050319: Radio Observations
  88. GRB 050319: NIR afterglow candidate
  89. GRB 050319:Near IR afterglow
  90. GRB 050318: SWIFT-UVOT refined analysis
  91. GRB 050319 : Confirmation of optical afterglow decay
  92. GRB 050319: Swift-BAT refined analysis
  93. GRB050319,optical observation
  94. GRB 050318: Swift/UVOT detection of afterglow emission
  95. RXTE Observations of GRB050318
  96. GRB050223: analysis of the XMM-Newton observation
  97. GRB050316: MASTER before, simultanious and follow up optical
  98. GRB 050306: ROTSE-III early limits
  99. GRB050316: MASTER optical observations
  100. GRB 050315: Swift-BAT further refined analysis

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