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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"

25822 results found.

  1. GRB 080413A: Swift-XRT refined analysis
  2. GRB 080413A, Swift-BAT refined analysis
  3. GRB 080413A Bootes observation
  4. GRB080413B: REM NIR & Optical Observation
  5. GRB 080413B: GROND detection of afterglow in all bands
  6. GRB 080413B: Swift detection of a possibly short burst with optical counterpart
  7. GRB 080413A: REM detection of the NIR Afterglow
  8. GRB 080413: Enhanced Swift-XRT position
  9. GRB 080413: TAROT Calern observatory optical observations
  10. GRB 080413: Swift detection of a burst with an optical afterglow
  11. GRB 080413: ROTSE-III Detection of Optical Counterpart
  12. GRB 080411: Swift/UVOT refined analysis
  13. GRB 080411, Swift-BAT refined analysis
  14. GRB 080411: Swift-XRT Refined Analysis
  15. GRB 080411: Enhanced Swift-XRT position
  16. GRB 080411: GROND detection of optical afterglow candidate
  17. GRB 080411: Swift detection of a bright burst
  18. GRB 080409: Swift-BAT refined analysis
  19. GRB 080408: GROND detection of optical/NIR afterglow candidate
  20. GRB 080330 optical observations
  21. Swift/UVOT observations of GRB080409
  22. GRB 080409: Swift XRT refined analysis
  23. GRB 080408: Swift-XRT position of a possible afterglow
  24. GRB 080409: Enhanced Swift-XRT position
  25. GRB 080409: REM optical/NIR observations
  26. GRB 080409: Swift detection of a burst
  27. GRB 080408: Analysis of AGILE Gamma-ray data
  28. GRB 080408: GRB Localization by SuperAGILE
  29. GRB 080319A: Early RAPTOR optical limits
  30. GRB 080319B: HST observations
  31. GRB 080319B: Potential Jet Break Observed by Swift-XRT and UVOT
  32. GRB 080405: Swift-BAT refined analysis
  33. GRB 080405: Swift-XRT position
  34. GRB 080405: Mars Oddysey and Swift-BAT detection, possible host galaxy
  35. GRB 080325: optical upper limit
  36. GRB 080328: GAO 150cm telescope Optical Observation
  37. GRB080330: Improved Swift XRT Position
  38. GRB080330: optical observations
  39. GRB080328, RIMOTS optical upper limit
  40. GRB080330: Swift XRT refined analysis
  41. GRB 080330: REM optical observations
  42. GRB 080330 Swift-UVOT refined analysis
  43. GRB 080328: Suzaku WAM observation of the prompt emission
  44. GRB080330: TNT optical observations
  45. GRB 080330, Swift-BAT refined analysis
  46. Konus-Wind observation of GRB 080328
  47. GRB 080330: GROND Observations
  48. GRB 080330: TAROT Calern observatory optical observations
  49. GRB 080330A: PAIRITEL Infrared Detections
  50. GRB 080330: error in reported XRT position
  51. GRB080330 - SDSS Pre-Burst Observations
  52. GRB 080330A: ROTSE-III Detection of Optical Counterpart
  53. GRB 080330: Swift detection of a burst with an optical counterpart
  54. GRB 080330: TAROT Calern observatory optical detection
  55. GRB 080328, Swift-BAT refined analysis
  56. GRB 080325, Swift-BAT refined analysis
  57. Swift/UVOT observations of GRB080328
  58. GRB080319B, BVRcIc field calibration
  59. GRB 080328: Enhanced Swift-XRT position
  60. GRB 080328: Swift detection of a burst with an optical counterpart
  61. GRB 080325: Subaru detection of NIR afterglow candidate
  62. GRB 080325: GROND Observations
  63. GRB 080325: Swift/UVOT Upper Limits
  64. GRB 080325: Early observations from OSN
  65. GRB 080325: NIR afterglow candidate
  66. GRB 080319D: GROND Detection of the Optical Counterpart
  67. GRB 080325: Enhanced Swift-XRT position
  68. GRB 080325: Swift detection of a burst
  69. GRB 080319B : Apparent spectral evolution in very early Swift/XRT WT mode data: intrinsic or pile-up effect?
  70. GRB 080319B: Spitzer Mid-infrared Observations
  71. GRB 080319C: Suzaku WAM observation of the prompt emission
  72. Radio Detection of GRB 080319B
  73. GRB 080320, Swift-BAT refined analysis
  74. GRB 080319D: GROND Observations
  75. GRB 080319B: optical upper limit
  76. GRB 080319D: optical upper limit
  77. GRB 080319D, Swift-BAT refined analysis
  78. GRB 080319C: UVOT Observations
  79. GRB 080319B: UVOT Observations
  80. GRB 080319A: UVOT Observations
  81. GRB 080320: Swift XRT refined analysis
  82. GRB 080320: J detection with FLAMINGOS
  83. GRB 080319D: Swift XRT refined analysis
  84. GRB 080320: optical limit
  85. GRB 080320: Gemini-N optical afterglow
  86. GRB 080319C, Swift-BAT refined analysis
  87. GRB 080320: Enhanced Swift-XRT position
  88. GRB 080320 - SDSS Pre-Burst Observations
  89. GRB 080320: Swift detection of a burst
  90. GRB 080319B : Lulin observation of temporal break at 0.2 days
  91. GRB 080319C - SDSS Pre-Burst Observations
  92. GRB 080319A SDSS Pre-Burst Observations
  93. GRB080319B - SDSS Pre-Burst Observations
  94. GRB 080319A: Swift-XRT Team Refined Analysis
  95. GRB 080319B, Swift-BAT refined analysis
  96. GRB 080319C: Swift-XRT Team Refined Analysis
  97. GRB 080319B: Swift-XRT Team Refined Analysis
  98. GRB 080319D: Swift/UVOT Refined Analysis of the Fading Optical Afterglow Candidate
  99. GRB 080319C: AGILE-MCAL observation of the prompt emission
  100. GRB 080319D: MASTER-VWF-Kislovodsk optical observation

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