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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"

21526 results found.

  1. GRB 090531: GROND upper limits
  2. GRB 090531: Swift detection of a burst
  3. GRB090530: Swift XRT refined analysis
  4. GRB090530: Swift/UVOT afterglow detection
  5. GRB 090529: Swift-XRT refined analysis
  6. GRB 090529: OSN optical observations
  7. GRB 090530: Enhanced Swift-XRT position
  8. GRB 090530: Swift-BAT refined analysis
  9. GRB 090530: PAIRITEL NIR Detections
  10. GRB 090530A: ROTSE-III Detection of Optical Counterpart
  11. GRB 090530: Swift detection of a burst with an optical counterpart
  12. GRB 090529: optical observations
  13. GRB 090529: TLS Afterglow Observations
  14. GRB090529: UVOT/Swift detection of a brightening optical afterglow
  15. GRB 090529: Swift-BAT refined analysis
  16. GRB 090529: Enhanced Swift-XRT position
  17. GRB 090529: Preliminary Swift/UVOT Upper Limit
  18. GRB 090529: Xinglong TNT optical observation
  19. GRB 090529: Swift detection of a burst
  20. GRB 090520B: Fermi GBM detection
  21. GRB 090518 - NOT upper limit
  22. GRB 090516A: Konus-Wind and Swift/BAT joint spectral analysis
  23. GRB 090518: Fermi GBM detection
  24. GRB 090520 Swift-BAT detection of a burst in ground analysis
  25. GRB 090423: Fermi GBM T90 follow-up analysis results
  26. GRB 090516: Fermi GBM observation
  27. GRB 090519: Swift-XRT refined analysis
  28. GRB 090519: GROND observation
  29. GRB 090519: Swift/UVOT Upper Limits
  30. GRB 090519, Swift-BAT refined analysis
  31. GRB 090519: Enhanced Swift-XRT position
  32. GRB 090519: Limits from BOOTES-1B
  33. GRB 090519: NOT afterglow candidate
  34. GRB 090519: FARO Chante Perdrix Observatory optical observations
  35. GRB 090519: TAROT Calern observatory optical observations
  36. GRB 090519: Swift detection of a burst
  37. GRB 090518: Swift/UVOT Upper Limits
  38. GRB090518: GROND upper limits
  39. GRB 090518: P60 Observations
  40. GRB 090518, Swift-BAT refined analysis
  41. GRB 090516, RIMOTS optical upper limits
  42. GRB090518 : Optical upper limit by MOA-II telescope
  43. GRB 090518: Swift-XRT refined analysis
  44. GRB 090518: Enhanced Swift-XRT position
  45. GRB 090518: Swift detection of a burst
  46. GRB 090515: Swift/BAT spectral lag results
  47. GRB 090516: Swift-BAT refined analysis
  48. GRB 090516: GROND OBSERVATIONS
  49. GRB 090516 - Zadko Telescope observations
  50. GRB 090516: Swift XRT refined analysis
  51. GRB 090516: Swift/UVOT Observations
  52. GRB 090516: Enhanced Swift-XRT position
  53. GRB 090516: Faulkes Telescope South optical afterglow
  54. GRB 090516: Swift detection of a burst
  55. GRB 090515: VLA observations
  56. GRB 090515: Lick Upper Limits
  57. GRB 090515: ROVOR Upper Limit
  58. GRB 090515: MMT/MMIRS NIR Upper Limit
  59. GRB 090515: Swift/UVOT Observations
  60. GRB 090515: Swift-XRT refined analysis
  61. GRB 090515: Enhanced Swift-XRT position
  62. GRB 090509: Fermi GBM observation
  63. GRB 090515: Swift-BAT refined spectral analysis
  64. GRB 090515: Swift-BAT refined analysis
  65. GRB 090509 - Zadko Telescope observations
  66. GRB 090515: Gemini-N upper limit
  67. GRB 090515: Super-LOTIS Upper Limits
  68. GRB 090515: PAIRITEL Upper Limits
  69. GRB 090515: KAIT optical upper limits
  70. GRB 090515: ROTSE-III Optical Limits
  71. GRB 090515: Swift detection of a short burst
  72. GRB 090510: Suzaku WAM observation of the prompt emission
  73. GRB090510: VLT/FORS2 spectroscopic redshift
  74. GRB 090510: GROND observations
  75. GRB 090510: Swift/UVOT host galaxy candidates
  76. GRB 090510: Fermi-LAT follow-up analysis
  77. GRB 090509, further Swift-BAT refined analysis
  78. Konus-Wind observation of GRB 090510
  79. GRB 090510: UVOT refined analysis
  80. GRB 090510: Swift XRT refined analysis
  81. GRB 090510: Enhanced Swift-XRT position
  82. GRB 090510: NOT afterglow confirmation
  83. GRB 090510: Swift-BAT refined analysis
  84. GRB 090510: Fermi GBM detection
  85. GRB 090509: Swift-BAT refined analysis
  86. Fermi LAT detection of GRB 090510
  87. GRB 090510: Swift/UVOT Detection of a Candidate Optical Afterglow
  88. GRB 090510: Swift detection of a short hard burst
  89. GRB 090408: optical upper limit
  90. GRB 090418A: optical observation
  91. GRB 090509: GROND afterglow candidate
  92. GRB 090509: Swift detection of a burst
  93. GRB 090423: optical limit
  94. GRB 090424: optical observations
  95. GRB 090429A: ROVOR magnitude limit
  96. GRB 090426: optical observations
  97. GRB 090429D: Fermi GBM detection
  98. GRB 090429B: Swift/UVOT Upper Limits
  99. GRB 090429A: Swift/UVOT Upper Limits
  100. GRB 090429A: Swift-XRT refined analysis

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