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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"

18779 results found.

  1. GRB 100728B: Swift/UVOT Observations (correction to GCN 11028)
  2. GRB 100728B: Swift/UVOT Observations (correction)
  3. GRB 100728B: Swift/UVOT Observations
  4. GRB 100728B: Lick Observations
  5. GRB 100728B, Swift-BAT refined analysis
  6. GRB 100728B: Swift-XRT Refined Analysis
  7. Konus-Wind observation of GRB 100728A
  8. GRB 100728A: GROND Detection of the NIR Afterglow Candidate
  9. GRB 100727A: Swift/UVOT Upper Limits
  10. GRB 100728A, Swift-BAT refined analysis
  11. GRB 100728B: Enhanced Swift-XRT position
  12. GRB 100728A: Swift/UVOT Upper Limits
  13. GRB 100728B: Fermi GBM observation
  14. GRB 100728A: Swift-XRT refined analysis
  15. GRB 100728B: GROND Detection of the NIR Afterglow
  16. GRB 100728B: optical detection
  17. GRB 100728B: Skynet/PROMPT Detections (correction)
  18. GRB 100728B: KAIT optical afterglow detection (correction)
  19. GRB 100728B: Swift detection of a burst with an optical counterpart
  20. GRB 100728A: Skynet/PROMPT Detections
  21. GRB 100728A: Fermi GBM observation
  22. GRB 100728A: Enhanced Swift-XRT position
  23. GRB 100728A: Swift detection of a burst
  24. GRB 100727A: Swift XRT refined analysis
  25. GRB 100727A: Fermi GBM observation
  26. GRB 100727A, Swift-BAT refined analysis
  27. GRB 100727A: Enhanced Swift-XRT position
  28. GRB100727A: MOA optical upper limit
  29. GRB 100727A: Swift detection of a burst
  30. GRB 100725B: Swift-BAT refined analysis
  31. GRB 100725B: refined XRT analysis
  32. GRB 100725B: Swift/UVOT Upper Limits
  33. GRB 100725A: Swift/UVOT Upper Limits
  34. GRB 100725A: Swift-BAT refined analysis
  35. GRB 100725A: Swift XRT refined analysis
  36. GRB 100725B: Enhanced Swift-XRT position
  37. GRB 100725A: Enhanced Swift-XRT position
  38. GRB100725B: Faulkes Telescope North observations
  39. GRB 100725B: Swift detection of a burst
  40. GRB 100725A: Prompt enhanced Swift-XRT position
  41. GRB 100725A: Swift detection of a burst
  42. GRB 100724A: Swift/BAT spectral lag results
  43. GRB 100724A: Swift XRT refined analysis
  44. GRB 100724A: Enhanced Swift-XRT position
  45. GRB 100724A: Swift/UVOT observations
  46. GRB 100724A: Swift-BAT refined analysis
  47. GRB 100724A, GROND detection of an afterglow candidate
  48. GRB 100724A: Swift detection of a burst
  49. GRB 100614A: 10.4-m GTC deep-optical limit
  50. GRB 100719A: Swift-BAT refined analysis
  51. GRB 100719A: Swift detection of a burst
  52. GRB 100713A: Swift XRT refined analysis
  53. GRB 100713A : IRSF/SIRIUS NIR upper limits
  54. GRB100713A: Swift/UVOT observations
  55. GRB 100713A: GROND upper limits
  56. GRB 100713A: optical upper limit
  57. GRB 100713A: TELMA and 1.5m OSN optical observations
  58. GRB100713A: Swift X-ray afterglow detection
  59. GRB 100628A: Chandra observations
  60. GRB 100628A: Swift XRT/UVOT refined analysis
  61. Tentative redshift of GRB100704A from Swift-XRT data
  62. Konus-Wind observation of GRB 100704A
  63. GRB 100704A: Swift XRT refined analysis
  64. GRB 100704: Swift/UVOT Upper Limits
  65. GRB 100704A: Fermi GBM observation
  66. GRB 100704A: Swift-BAT refined analysis
  67. GRB100704A: MOA optical upper limit
  68. GRB 100704A: Enhanced Swift-XRT position
  69. GRB 100704A: Swift detection of a burst
  70. GRB 100702A, Swift-BAT refined analysis
  71. GRB 100702A: Swift XRT refined analysis
  72. Swift/UVOT observations of GRB100702A - correction
  73. Swift/UVOT observations of GRB100702A
  74. GRB 100702: ROTSE-III Optical Limits
  75. GRB 100702A: Swift detection of a short burst
  76. GRB 100615A: Chandra X-ray ToO Observation
  77. GRB 100213B: Detection of Fading Optical Afterglow
  78. GRB 100625A: Fermi GBM detection
  79. GRB 100628A: Swift XRT refined position
  80. GRB100625A: GROND confirmation of constant source
  81. GRB100628A : MOA optical upper limit
  82. GRB 100628A: Swift/UVOT Upper Limits
  83. GRB 100628A: Swift XRT detection of a possible X-ray afterglow
  84. GRB 100628A: INTEGRAL SPI-ACS light curve
  85. GRB 100628A: Swift-BAT refined analysis
  86. GRB 100628A: Swift detection of a short hard burst
  87. Swift-BAT trigger 426048 is not a burst
  88. GRB 100614A: CrAO optical limit
  89. GRB 100625A: Swift/UVOT Upper Limits
  90. GRB 100625A: Swift-BAT refined analysis
  91. Konus-Wind observation of GRB 100625A
  92. GRB 100625A : IRSF/SIRIUS NIR upper limit
  93. GRB 100625A: Swift-XRT Team refined analysis
  94. GRB 100625A: Enhanced Swift-XRT position
  95. GRB100625A : MOA optical upper limit
  96. GRB 100625A: Swift detection of a short hard burst
  97. GRB 100418A: late time optical observations
  98. Konus-Wind observation of GRB 100621A
  99. GRB 100621A: IRSF/SIRIUS NIR Observation
  100. GRB 100621A MOA-II optical limit

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