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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"

20866 results found.

  1. Swift/BAT possible detection of a weak burst GRB050430
  2. GRB050416a: Radio Detection
  3. GRB 050422: Swift-BAT refined analysis
  4. Swift Detection of GRB 050422
  5. GRB 050421: SLOTIS observations
  6. GRB 050421: Further Analysis of IR imaging
  7. GRB050421: Radio Observations
  8. GRB050421: Radio Observations
  9. GRB 050421: IR Observations
  10. GRB 050421: ROTSE-III Optical Limits
  11. GRB 050421: NIR observations re-examination
  12. GRB050421
  13. GRB 050421: early Swift XRT analysis results
  14. GRB 050421: NIR observations
  15. GRB050421: P60 Observations
  16. GRB 050421: BOOTES-2 simultaneous optical observations
  17. Swift Detection of GRB050421
  18. GRB 050416b: Tentative Swift XRT Position
  19. GRB 050315: potential host galaxy
  20. GRB050326: analysis of the XMM-Newton observation
  21. GRB050418: Null Optical Observations
  22. GRB050416A, optical observations
  23. GRB 050418: Swift-BAT refined analysis
  24. GRB 050416: Mitsume optical observation
  25. GRB 050416b: Swift-BAT refined analysis
  26. GRB050416B: IR observations
  27. GRB050412: Radio Observations
  28. GRB 050416: Swift/UVOT detection of afterglow emission
  29. GRB 050416: Swift-BAT refined analysis
  30. GRB 050416,optical observation
  31. GRB050416: P200 NIR Observations
  32. GRB 050416: Radio observations
  33. Swift BAT/XRT Detection of GRB 050416
  34. GRB 050412: Subaru observations
  35. GRB 050412: PROMPT VRcIc Observations
  36. GRB 050408: Kuiper 1.5m observations
  37. GRB 050412 : XingLong optical observation
  38. GRB 050412: Swift-BAT refined analysis
  39. GRB 050412: Early Optical/Ultraviolet Observations with
  40. GRB 050408: SDSS Field Calibration
  41. GRB 050412: Optical limit
  42. GRB050412: P60 Observations
  43. GRB050412: ROTSE-III Optical Limits
  44. Swift-BAT Detection of GRB 050412: A Bright, Long Burst
  45. GRB 050412: IR and Optical observations
  46. GRB 050412: IR Observations
  47. GRB050408: Radio Observations
  48. GRB 050401: Optical limit
  49. GRB 050408: Optical limit
  50. GRB050410: P60 Observations
  51. GRB 050410: Early Optical/Ultraviolet Observations with Swift/UVOT
  52. GRB 050410, optical observations
  53. GRB 050408: PROMPT VRcIc Observations
  54. GRB 050408: Early Optical/Ultraviolet Observations with Swift/UVOT
  55. GRB050410: Radio Observations
  56. GRB050410: MASTER optical observations
  57. GRB 050410: Early observations with Swift-UVOT
  58. GRB 050408: Inconsistency of host galaxy identification
  59. GRB 050408: Subaru Observations
  60. GRB 050408: WIDGET simultaneous optical observations
  61. GRB 050408: Properties of the Host Galaxy
  62. GRB050408: Radio Observations
  63. GRB 050408, optical observations
  64. GRB050408: REM NIR and Optical observation
  65. GRB 050408,optical observation
  66. GRB 050408: Emission and absorption redshift
  67. GRB 050408: Mercator Optical Observations
  68. GRB 050408: Optical afterglow confirmed
  69. GRB 050408: opitcal observation
  70. GRB 050408, optical observations
  71. GRB 050408: Swift XRT Position
  72. GRB 050408: ROTSE-III Optical Limits
  73. GRB050408: MASTER optical observations
  74. GRB050401: Radio Detection
  75. GRB 050406: Magellan optical observations
  76. GRB 050406 BAT refined analysis
  77. GRB 050406: Early observations with Swift-UVOT
  78. Swift-BAT detection of GRB 050406
  79. GRB050401, radio observation at 4.8 GHz and 8.64 GHz
  80. GRB 050401 BAT refined analysis
  81. GRB050401: TNG R-band observation
  82. GRB 050402: Early observations with Swift-UVOT
  83. Swift Trigger 113225: P60 Observations
  84. GRB 050401: Optical afterglow confirmed
  85. GRB050331: No Afterglow Detected
  86. GRB 050331: Swift UVOT Source
  87. Konus-Wind observation of GRB 050326
  88. GRB 050326: Early observations with Swift-UVOT
  89. GRB 050326 XMM-Newton observation
  90. GRB 050326: Swift XRT Position
  91. GRB050326: optical limit 33min before GRB
  92. GRB 050326 BAT refined analysis
  93. GRB050326: delayed XRT observation
  94. GRB050319, optical observations
  95. GRB050319: optical observation, March 20-22
  96. GRB050319: RTT150 Optical Observations
  97. GRB050319: VLA Observations
  98. GRB050319: radio observation
  99. GRB 050319: Swift-UVOT detection of the afterglow
  100. GRB050319: Radio Observations

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