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GCN Circulars

GCN Circulars are rapid bulletins submitted by and distributed to the community. 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"

28221 results found.

  1. GRB 050412: LCO Optical Observations
  2. GRB 050412: Optical observations
  3. GRB050412: P60 Observations
  4. GRB 050412: Swift XRT Position
  5. Swift-BAT Detection of GRB 050412: A Bright, Long Burst
  6. GRB 050412: IR Observations
  7. GRB050408: Radio Observations
  8. GRB 050401: Optical limit
  9. GRB 050408: Optical limit
  10. GRB050410: P60 Observations
  11. GRB 050410: Early Optical/Ultraviolet Observations with Swift/UVOT
  12. GRB 050410, optical observations
  13. GRB 050408: PROMPT VRcIc Observations
  14. GRB 050408: Early Optical/Ultraviolet Observations with Swift/UVOT
  15. GRB050410 : Null detection report
  16. GRB 050410, optical observations
  17. GRB050410: Radio Observations
  18. GRB 050408: Swift XRT measurement of possible jet break
  19. GRB 050410: Early observations with Swift-UVOT
  20. Swift-BAT detection of GRB 050410
  21. GRB 050410: Swift XRT Position
  22. GRB 050408: Retraction of Proposed Host Galaxy
  23. GRB 050408: Inconsistency of host galaxy identification
  24. GRB 050408: Subaru Observations
  25. GRB 050408: WIDGET simultaneous optical observations
  26. GRB 050408: SOAR UBVRc Observations
  27. GRB 050408: Properties of the Host Galaxy
  28. GRB 050408: Mercator Optical Observations
  29. GRB050408: Radio Observations
  30. GRB 050408: Swift XRT analysis
  31. GRB 050408, SMARTS optical/IR afterglow observations
  32. GRB 050408: Optical limit at 20 min after the burst
  33. GRB 050408, optical observations
  34. GRB050408: REM NIR and Optical observation
  35. GRB 050408: Moderate-resolution Gemini Spectroscopy
  36. GRB 050408 Optical Observations
  37. GRB 050408: Emission and absorption redshift
  38. GRB 050408: Mercator Optical Observations
  39. GRB 050408: Magellan astrometry and photometry
  40. GRB 050408: Optical afterglow confirmed
  41. GRB 050408, optical observations
  42. GRB 050408 optical candidate
  43. GRB 050408: Swift XRT Position
  44. GRB050401: Radio Detection
  45. Swift-UVOT Optical Counterpart Candidate to XRF 050406
  46. GRB 050406: Magellan optical observations
  47. GRB 050406: early Swift XRT analysis results
  48. GRB 050406: Swift XRT Position
  49. Swift-BAT detection of GRB 050406
  50. GRB050401: Radio observation at 610 MHz with GMRT
  51. GRB 050401: VLT spectroscopic redshift
  52. GRB 050401 Optical Observations
  53. GRB050401: Maidanak optical observation
  54. GRB 050401 BAT refined analysis
  55. Very questionable identity of Swift-BAT GRB050402 (Trig=113225)
  56. GRB050401: TNG R-band observation
  57. GRB 050402A: IR Analysis
  58. GRB050402: XDSS counterpart
  59. GRB050401: ROTSE-III Detection of Prompt Optical Counterpart
  60. GRB 050401: Optical afterglow confirmed
  61. GRB 050401: Optical afterglow candidate
  62. Swift-BAT detection of GRB 050401
  63. GRB 050401: Prompt XRT position
  64. GRB050331: No Afterglow Detected
  65. Swift-BAT detection of GRB 050331b
  66. GRB 050331: Swift UVOT Source
  67. Swift-BAT detection of GRB 050331
  68. GRB 050331: Swift XRT Position
  69. GRB050319: radio observation
  70. GRB 050326 XMM-Newton observation
  71. GRB 050326: Swift XRT Position
  72. GRB050326: delayed XRT observation
  73. Swift-BAT detection of a bright GRB 050326
  74. GRB050319, color indices
  75. GRB050319: optical observation, March 20-22
  76. Swift-BAT detection of a bright outburst from SGR1806-20
  77. Swift-BAT trigger 112060 is not a real GRB
  78. GRB 050319: Absorption redshift from the Nordic Optical Telescope
  79. GRB 050319: ROTSE-III Refined Analysis
  80. Refined Swift XRT positions for GRB050315, GRB050318 and GRB050319
  81. GRB050319: VLA Observations
  82. GRB050319: radio observation
  83. GRB 050319 R band observations
  84. GRB 050319: Swift-UVOT detection of the afterglow
  85. GRB050319: Radio Observations
  86. GRB 050319: NIR afterglow candidate
  87. GRB 050319:Near IR afterglow
  88. GRB050319: BR optical photometry
  89. GRB 050318: Absorption redshift from Magellan
  90. GRB 050319: Optical observation
  91. GRB 050319 : Confirmation of optical afterglow decay
  92. Swift Detection of GRB 050319
  93. GRB 050319: Detection of Possible Optical Counterpart
  94. GRB 050318: Swift/UVOT detection of afterglow emission
  95. GRB 050318: Magellan optical afterglow identification
  96. GRB050318: Swift XRT position
  97. Swift-BAT detection of GRB 050318
  98. GRB 050315, SMARTS optical afterglow decay
  99. GRB050223: analysis of the XMM-Newton observation
  100. GRB 050306: ROTSE-III early limits

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