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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"
  1. GRB 050408 Optical Observations
  2. GRB 050408: Emission and absorption redshift
  3. GRB 050408: Mercator Optical Observations
  4. GRB 050408: Magellan astrometry and photometry
  5. GRB 050408: First Optical observations with TFOSC at the RTT150
  6. GRB 050408: steepening of the optical decay
  7. GRB 050408: Optical afterglow confirmed
  8. GRB 050408: opitcal observation
  9. GRB 050408, optical observations
  10. GRB 050408 optical candidate
  11. GRB 050408: Swift XRT Position
  12. GRB 050408: ROTSE-III Optical Limits
  13. GRB 050408 (=H3711): A Long X-Ray-Rich GRB Detected by HETE
  14. GRB050408: MASTER optical observations
  15. GRB050401: Radio Detection
  16. Swift-UVOT Optical Counterpart Candidate to XRF 050406
  17. GRB 050406: Magellan optical observations
  18. GRB 050406: early Swift XRT analysis results
  19. GRB 050406 BAT refined analysis
  20. GRB 050406: Early observations with Swift-UVOT
  21. GRB 050406: Swift XRT Position
  22. Swift-BAT detection of GRB 050406
  23. Konus-Wind observation of GRB 050401
  24. GRB050401: Radio observation at 610 MHz with GMRT
  25. GRB050401, radio observation at 4.8 GHz and 8.64 GHz
  26. GRB 050401: VLT spectroscopic redshift
  27. GRB 050401 Optical Observations
  28. GRB050401: Maidanak optical observation
  29. GRB 050401 BAT refined analysis
  30. Very questionable identity of Swift-BAT GRB050402 (Trig=113225)
  31. GRB050401: TNG R-band observation
  32. GRB 050402A: IR Analysis
  33. GRB050402: XDSS counterpart
  34. GRB 050402A: IR Observations
  35. GRB 050402: Early observations with Swift-UVOT
  36. Swift Trigger 113225: P60 Observations
  37. GRB050401: ROTSE-III Detection of Prompt Optical Counterpart
  38. GRB 050401: Optical afterglow confirmed
  39. GRB 050401: Optical afterglow candidate
  40. Swift-BAT detection of GRB 050401
  41. GRB 050401: Prompt XRT position
  42. Retraction of three Swift GRB triggers
  43. GRB050331: No Afterglow Detected
  44. Swift-BAT detection of GRB 050331b
  45. GRB 050331: Swift UVOT Source
  46. Swift-BAT detection of GRB 050331
  47. GRB 050331: Swift XRT Position
  48. Swift Data Publicly Available Starting April 5, 2005
  49. GRB050319: radio observation
  50. Konus-Wind observation of GRB 050326
  51. GRB050326: optical limit
  52. GRB 050326: Early observations with Swift-UVOT
  53. GRB 050326 XMM-Newton observation
  54. GRB 050326 : Planned XMM-Newton observation
  55. GRB 050326: Swift XRT Position
  56. GRB050326: optical limit 33min before GRB
  57. GRB 050326 BAT refined analysis
  58. GRB050326: delayed XRT observation
  59. Swift-BAT detection of a bright GRB 050326
  60. GRB050319, optical observations
  61. GRB050319, color indices
  62. GRB050319: optical observation, March 20-22
  63. GRB050319: RTT150 Optical Observations
  64. Swift-BAT detection of a bright outburst from SGR1806-20
  65. Swift-BAT trigger 112060 is not a real GRB
  66. GRB 050319: Absorption redshift from the Nordic Optical Telescope
  67. GRB 050319: ROTSE-III Refined Analysis
  68. GRB 050318: Swift-BAT refined analysis
  69. Refined Swift XRT positions for GRB050315, GRB050318 and GRB050319
  70. GRB050319: VLA Observations
  71. GRB050319: radio observation
  72. GRB 050319 R band observations
  73. GRB 050319: Swift-UVOT detection of the afterglow
  74. GRB 050315: Variability Analysis of Swift BAT Time History
  75. GRB050319: Radio Observations
  76. GRB 050319: NIR afterglow candidate
  77. GRB 050319:Near IR afterglow
  78. GRB050319: BR optical photometry
  79. GRB 050318: SWIFT-UVOT refined analysis
  80. GRB 050318: Absorption redshift from Magellan
  81. GRB 050319: Optical observation
  82. GRB 050319 : Confirmation of optical afterglow decay
  83. GRB 050319: Swift-BAT refined analysis
  84. GRB050319,optical observation
  85. Swift Detection of GRB 050319
  86. GRB 050319: Detection of Possible Optical Counterpart
  87. GRB 050318: Swift/UVOT detection of afterglow emission
  88. GRB 050318: Magellan optical afterglow identification
  89. GRB050318: Swift XRT position
  90. RXTE Observations of GRB050318
  91. Swift-BAT detection of GRB 050318
  92. GRB 050315, SMARTS optical afterglow decay
  93. GRB050223: analysis of the XMM-Newton observation
  94. GRB050316: MASTER before, simultanious and follow up optical
  95. GRB 050306: ROTSE-III early limits
  96. GRB050316: MASTER optical observations
  97. GRB 050315: Swift-BAT further refined analysis
  98. GRB 050315, SMARTS optical/IR afterglow observations
  99. GRB 050315 I-band observations
  100. GRB050315: Radio afterglow

Advanced

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