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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"

27019 results found.

  1. GRB 091215: Faulkes Telescope North observations
  2. Trigger 379449: Swift detection of a possible burst
  3. GRB 091208A: Suzaku WAM observation of the prompt emission
  4. GRB 091208A: GAO 150cm telescope Optical Observation
  5. Konus-Wind observation of GRB 091208A
  6. GRB 091208B: GAO 150cm telescope Optical Observation
  7. GRB091208A: Swift/UVOT refined analysis
  8. GRB 091208B: GROND observations
  9. GRB 091208A: Swift-XRT observations
  10. GRB091208B: NOT optical observations
  11. GRB 091208B: Swift-XRT refined analysis
  12. GRB091208B: Swift/UVOT refined analysis
  13. GRB 091208B: Fermi GBM observation
  14. GRB 091208B, Swift-BAT refined analysis
  15. GRB 091208A Swift-BAT refined analysis
  16. GRB 091208B: Faulkes Telescope North and South Optical Afterglow
  17. GRB 091208A, RIMOTS optical upper limits
  18. GRB 091208B: MITSuME Akeno Optical Observation
  19. GRB 091208B: MITSuME Okayama Optical Observation
  20. GRB 091208B, RIMOTS optical upper limits
  21. GRB 091208B: Swift detection of a burst with an optical afterglow
  22. GRB 091208B: BOOTES-3 optical afterglow
  23. GRB 091208: ROTSE-III Optical Limits
  24. GRB 091208: Swift detection of a burst
  25. GRB 091123: Suzaku WAM observation of the prompt emission
  26. GRB 091127: Skynet/PROMPT Observations of Possible Host Galaxy
  27. GRB 091127: GAO 150cm telescope Optical Observation
  28. GRB 091109A: GROND confirmation of redshift z = 3.5
  29. GRB091127: Continuing Swift/UVOT Observations
  30. GRB091202: Swift-XRT refined analysis
  31. GRB 091202: Swift/UVOT Upper Limits
  32. GRB 091202: Liverpool Telescope observations
  33. GRB 091127: Zadko Telescope Observations
  34. GRB 091126A: Suzaku WAM observation of the prompt emission
  35. GRB 091202: TAROT Calern observatory optical observations
  36. GRB 091202: Liverpool Telescope Observations
  37. GRB 091117: Chandra Observations
  38. GRB 091127: Skynet/PROMPT Continued Observations of Fading
  39. GRB 091123: Fermi GBM detection of a very long burst
  40. GRB 091126B: Fermi GBM detection
  41. GRB 091127: Suzaku WAM observation of the prompt emission
  42. GRB 091126: Fermi GBM detection
  43. GRB 091130B: Swift-XRT team refined analysis
  44. GRB 091130B: Swift-BAT refined analysis
  45. GRB 091130B: Swift/UVOT Upper Limits
  46. GRB 091127: Skynet/PROMPT Observations of Fading
  47. Swift trigger 377436 (possible GRB 091130A) is not a burst
  48. GRB 091130B: Swift detection of a burst
  49. GRB 091130: Swift detection of a possible burst
  50. GRB 091128: Fermi GBM detection
  51. Konus-Wind observation of GRB 091127
  52. GRB 091127: TAROT La Silla observatory optical observations
  53. GRB 091127: Further NOT optical observations
  54. GRB 091127: Fermi GBM detection
  55. GRB 091127: Swift-XRT afterglow detection and analysis
  56. GRB 091127: TAROT La Silla observatory optical decay
  57. GRB 091127: Swift/UVOT observations
  58. GRB 091127: Swift-BAT refined analysis
  59. GRB 091127 : GROND observations
  60. GRB 091127: Swift/UVOT Detection of an Optical Afterglow
  61. GRB 091127: Liverpool Telescope afterglow candidate
  62. GRB 091127: Swift detection of a burst
  63. GRB 091120: MAXI GSC detection
  64. GRB 091120: Fermi GBM observation
  65. GRB 091117A: Suzaku WAM observation of the prompt emission
  66. GRB 091117A: Swift/UVOT followup observations
  67. GRB 091117: Swift-XRT observations
  68. GRB 091117 BAT refined analysis
  69. GRB091117: Gemini South Observations
  70. GRB 091117: Swift XRT refined analysis
  71. GRB 091117A Detected in ground analysis of BAT data and IPN triangulation
  72. GRB 091112: Suzaku WAM observation of the prompt emission
  73. GRB 091102A: Suzaku WAM observation of the prompt emission
  74. GRB 091109B: Suzaku WAM observation of the prompt emission
  75. GRB091111: Swift XRT refined analysis
  76. Konus-Wind and Konus-RF observations of GRB 091031
  77. GRB 091112: Swift-BAT refined analysis
  78. GRB 091112: Fermi GBM observation
  79. GRB 091031: Fermi LAT detection of a faint burst
  80. GRB 091112: Swift detection of a possible burst
  81. GRB 091109B: Swift/UVOT Upper Limits
  82. GRB 091109B: Swift-XRT Team refined analysis
  83. GRB 091109B: Swift-BAT refined analysis
  84. GRB 091109B: ROTSE-III Optical Limits
  85. GRB 091109B: Swift detection of a short burst
  86. GRB 091030: Fermi GBM detection
  87. GRB 091109: Swift-XRT refined analysis
  88. GRB 091109: Swift/UVOT observations
  89. GRB 091109: Swift-BAT refined analysis
  90. GRB 091109: Swift detection of a burst with optical afterglow
  91. GRB 091029: Observations from Stardome Observatory
  92. GRB 091104: Swift-BAT refined analysis
  93. GRB 091104: Swift XRT Refined Analysis
  94. GRB 091104: Swift/UVOT Upper Limits
  95. GRB 091104: Swift detection of a burst
  96. Fermi LAT Upper Limits on GRB 091010
  97. GRB 091102A: Fermi GBM observation
  98. GRB 091102: Swift-XRT refined analysis
  99. GRB 091102: Swift/UVOT Upper Limits
  100. GRB 091102: GROND Upper Limits

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