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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"

18568 results found.

  1. GRB 070512: IPN localization and Konus spectrum of a bright burst
  2. GRB 070508: pseudo-z from 4 different spectral analyses
  3. GRB 070509: Swift/UVOT Upper Limits
  4. Konus-Wind and Konus-A observation of GRB 070508
  5. Swift-BAT trigger 278987 is not a GRB
  6. GRB 070510: Swift detection of a possible burst
  7. GRB070509: Swift-XRT Refined Analysis
  8. GRB 070509, Swift-BAT refined analysis
  9. GRB 070508: Suzaku/WAM observation of the prompt emission
  10. GRB 070509: REM observations
  11. GRB 070509: Swift detection of a burst
  12. GRB 070509: ROTSE-III Optical Limits
  13. GRB070508: Swift/UVOT Observations
  14. GRB 070508, Swift-BAT refined analysis
  15. GRB 070508: Swift-XRT refined analysis
  16. GRB 070508: TAROT La Silla observatory optical observations
  17. GRB 070508: Swift detection of an intense burst with an optical counterpart
  18. GRB070412: MAGIC telescope GeV observation
  19. Swift-BAT trigger 278809 is not a GRB
  20. GRB 070507: Swift detection of a possible cosmic ray shower event or a possible burst
  21. GRB070506: Swift/UVOT Observations
  22. GRB070506: Swift XRT refined analysis
  23. GRB 070506, Swift-BAT Refined Analysis
  24. GRB 070506: Swift detection of a burst with optical afterglow
  25. GRB 070429A: Swift XRT further analysis
  26. GRB 070309: Swift-XRT afterglow confirmation
  27. VLA observation of GRB 070429B
  28. Swift/UVOT observations of GRB070429B
  29. GRB 070429B, Swift-BAT refined analysis
  30. Swift/UVOT observations of GRB070429A
  31. GRB 070429A: Swift XRT refined analysis
  32. GRB 070429A, Swift-BAT refined analysis
  33. GRB 070429B: Swift XRT refined analysis
  34. GRB 070429B: ROTSE-III Optical Limits
  35. GRB 070429B: Swift detection of a short burst
  36. GRB 070429: ROTSE-III Optical Limits
  37. GRB 070429: Swift detection of a burst
  38. GRB 070427, Swift-BAT Refined Analysis
  39. GRB 070427: Swift detection of a burst
  40. GRB070419B: Suzaku WAM observation of the prompt emission
  41. GRB 070411, deep LBT photometry
  42. GRB 070420: pseudo-z~1.56 from spectral parameters of the prompt
  43. GRB 070420 Swift-BAT Refined Analysis
  44. GRB070419A: Kuiper Optical detection
  45. GRB070419a: Swift UVOT observations
  46. GRB 070419A: MARGE Observations
  47. GRB 070420: optical rebrightening observed at Mt. John
  48. GRB 070420: Swift XRT refined analysis
  49. GRB070420: Swift UVOT continuing observations
  50. GRB 070420: Faulkes Telescope South Observations
  51. GBR 070419A: Swift/XRT refined analysis
  52. GRB 070420: TAROT La Silla observatory optical observations
  53. GRB 070420: NIR and optical afterglow confirmed
  54. GRB 070420: Swift detection of a burst with optical afterglow
  55. GRB 070419A: Early Super-LOTIS Observations
  56. GRB 070419B, Swift-BAT refined analysis
  57. GRB 070419A Swift-BAT Refined Analysis
  58. GRB 070419A: RAPTOR Detection of Early Emission
  59. GRB 070419B: Swift XRT refined analysis
  60. GRB 070419A, Optical observations
  61. GRB070419 - SDSS Pre-Burst Observations
  62. GRB 070419A: Faulkes Telescope North Optical Observations
  63. GRB 070419B optical afterglow candidate
  64. GRB 070419B: optical afterglow candidate
  65. GRB070419A, optical observation
  66. GRB070330: Correction to UVOT position
  67. GRB 070419B: Swift detection of a burst
  68. GRB 070419A: ROTSE-III Optical Limits
  69. GRB 070419: Swift detection of a burst
  70. Swift-BAT Trigger 276045 is a Cosmic Ray Shower event
  71. Trigger 276045: Swift detection of a possible burst
  72. GRB 070406: Swift XRT refined analysis
  73. GRB 070411: TLS data shows plateau, flares
  74. GRB070412: Swift UVOT observations
  75. GRB 070411: Swift/UVOT observations
  76. GRB 070412, Swift-BAT refined analysis
  77. GRB 070412: Swift-XRT refined analysis
  78. GRB 070411: Swift-XRT refined analysis
  79. GRB 070412: Optical observations at Crni Vrh
  80. GRB 070412: Swift-XRT refined position
  81. GRB 070411, Swift-BAT refined analysis
  82. GRB 070412: Swift detection of a burst
  83. GRB 070411: ROTSE-III Detection of Optical Counterpart
  84. GRB 070411: Tautenburg RRM Afterglow Confirmation
  85. GRB 070411: Swift detection of a burst with optical afterglow
  86. GRB 070406: Swift XRT team further analysis
  87. GRB 070406: Astrometrically Refined XRT Position, Unfading Source
  88. GRB 070406, Swift-BAT refined analysis
  89. GRB070406: Swift UVOT observations
  90. GRB 070406: Swift XRT Team analysis - Possible X-ray counterpart
  91. GRB 070406: SARA upper limit
  92. GRB 070406: Xinglong TNT optical Upper Limit
  93. GRB 070406: Swift detection of a burst
  94. INTEGRAL ToO Observation of SGR1806-20
  95. UVOT observations of GRB070330
  96. GRB 070330, Swift-BAT refined analysis
  97. GRB 070330: TAROT La Silla observatory optical observations
  98. GRB 070330: Swift-XRT refined analysis
  99. GRB 070330: Swift detection of a burst
  100. GRB 070328: pseudo-z~2.75 from spectral parameters of the prompt

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