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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"

28038 results found.

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

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