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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"

18684 results found.

  1. GRB 100802A: Liverpool Telescope observations
  2. GRB 100802A: ROTSE-III Optical Limits
  3. GRB 100802A: Possible Swift/UVOT Detection of Optical Afterglow
  4. GRB 100802A: Swift detection of a burst
  5. GRB 100725B: TELMA optical observation
  6. GRB 100728B: Swift/UVOT Observations (correction to GCN 11028)
  7. GRB 100728B: Swift/UVOT Observations (correction)
  8. GRB 100728B: Swift/UVOT Observations
  9. GRB 100728B: Lick Observations
  10. GRB 100728B, Swift-BAT refined analysis
  11. GRB 100728B: Swift-XRT Refined Analysis
  12. Konus-Wind observation of GRB 100728A
  13. GRB 100728A: GROND Detection of the NIR Afterglow Candidate
  14. GRB 100727A: Swift/UVOT Upper Limits
  15. GRB 100728A, Swift-BAT refined analysis
  16. GRB 100728B: Enhanced Swift-XRT position
  17. GRB 100728A: Swift/UVOT Upper Limits
  18. GRB 100728B: Fermi GBM observation
  19. GRB 100728A: Swift-XRT refined analysis
  20. GRB 100728B: GROND Detection of the NIR Afterglow
  21. GRB 100728B: optical detection
  22. GRB 100728B: Skynet/PROMPT Detections (correction)
  23. GRB 100728B: KAIT optical afterglow detection (correction)
  24. GRB 100728B: Swift detection of a burst with an optical counterpart
  25. GRB 100728A: Skynet/PROMPT Detections
  26. GRB 100728A: Fermi GBM observation
  27. GRB 100728A: Enhanced Swift-XRT position
  28. GRB 100728A: Swift detection of a burst
  29. GRB 100727A: Swift XRT refined analysis
  30. GRB 100727A: Fermi GBM observation
  31. GRB 100727A, Swift-BAT refined analysis
  32. GRB 100727A: Enhanced Swift-XRT position
  33. GRB100727A: MOA optical upper limit
  34. GRB 100727A: Swift detection of a burst
  35. GRB 100725B: Swift-BAT refined analysis
  36. GRB 100725B: refined XRT analysis
  37. GRB 100725B: Swift/UVOT Upper Limits
  38. GRB 100725A: Swift/UVOT Upper Limits
  39. GRB 100725A: Swift-BAT refined analysis
  40. GRB 100725A: Swift XRT refined analysis
  41. GRB 100725B: Enhanced Swift-XRT position
  42. GRB 100725A: Enhanced Swift-XRT position
  43. GRB100725B: Faulkes Telescope North observations
  44. GRB 100725B: Swift detection of a burst
  45. GRB 100725A: Prompt enhanced Swift-XRT position
  46. GRB 100725A: Swift detection of a burst
  47. GRB 100724A: Swift/BAT spectral lag results
  48. GRB 100724A: Swift XRT refined analysis
  49. GRB 100724A: Enhanced Swift-XRT position
  50. GRB 100724A: Swift/UVOT observations
  51. GRB 100724A: Swift-BAT refined analysis
  52. GRB 100724A, GROND detection of an afterglow candidate
  53. GRB 100724A: Swift detection of a burst
  54. GRB 100614A: 10.4-m GTC deep-optical limit
  55. GRB 100719A: Swift-BAT refined analysis
  56. GRB 100719A: Swift detection of a burst
  57. GRB 100713A: Swift XRT refined analysis
  58. GRB 100713A : IRSF/SIRIUS NIR upper limits
  59. GRB100713A: Swift/UVOT observations
  60. GRB 100713A: GROND upper limits
  61. GRB 100713A: optical upper limit
  62. GRB 100713A: TELMA and 1.5m OSN optical observations
  63. GRB100713A: Swift X-ray afterglow detection
  64. GRB 100628A: Chandra observations
  65. GRB 100628A: Swift XRT/UVOT refined analysis
  66. Tentative redshift of GRB100704A from Swift-XRT data
  67. Konus-Wind observation of GRB 100704A
  68. GRB 100704A: Swift XRT refined analysis
  69. GRB 100704: Swift/UVOT Upper Limits
  70. GRB 100704A: Fermi GBM observation
  71. GRB 100704A: Swift-BAT refined analysis
  72. GRB100704A: MOA optical upper limit
  73. GRB 100704A: Enhanced Swift-XRT position
  74. GRB 100704A: Swift detection of a burst
  75. GRB 100702A, Swift-BAT refined analysis
  76. GRB 100702A: Swift XRT refined analysis
  77. Swift/UVOT observations of GRB100702A - correction
  78. Swift/UVOT observations of GRB100702A
  79. GRB 100702: ROTSE-III Optical Limits
  80. GRB 100702A: Swift detection of a short burst
  81. GRB 100615A: Chandra X-ray ToO Observation
  82. GRB 100213B: Detection of Fading Optical Afterglow
  83. GRB 100625A: Fermi GBM detection
  84. GRB 100628A: Swift XRT refined position
  85. GRB100625A: GROND confirmation of constant source
  86. GRB100628A : MOA optical upper limit
  87. GRB 100628A: Swift/UVOT Upper Limits
  88. GRB 100628A: Swift XRT detection of a possible X-ray afterglow
  89. GRB 100628A: INTEGRAL SPI-ACS light curve
  90. GRB 100628A: Swift-BAT refined analysis
  91. GRB 100628A: Swift detection of a short hard burst
  92. Swift-BAT trigger 426048 is not a burst
  93. GRB 100614A: CrAO optical limit
  94. GRB 100625A: Swift/UVOT Upper Limits
  95. GRB 100625A: Swift-BAT refined analysis
  96. Konus-Wind observation of GRB 100625A
  97. GRB 100625A : IRSF/SIRIUS NIR upper limit
  98. GRB 100625A: Swift-XRT Team refined analysis
  99. GRB 100625A: Enhanced Swift-XRT position
  100. GRB100625A : MOA optical upper limit

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