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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"

904 results found.

  1. SGR 1935+2154: MAXI/GSC detection
  2. GRB 160601A: Swift/UVOT Upper Limits
  3. Konus-Wind observation of GRB 160509A
  4. GRB 160509A: DCT Imaging / Afterglow Confirmation
  5. GRB 160509A: MAXI/GSC refined analysis
  6. GRB 160509A: Fermi GBM Detection
  7. GRB 160509A: optical observations
  8. Correction to GCN 19404; GRB 160509A: MAXI/GSC detection
  9. GRB 160227A: MAXI/GSC detection
  10. GRB 160227A: MAXI/GSC detection
  11. LIGO/Virgo G184098: MAXI/GSC search for an X-ray counterpart of GW150914
  12. GRB 160206A: Swift/UVOT observations
  13. GRB 160206A: Swift-XRT observations
  14. GRB 160206A: Tiled Swift observations
  15. GRB 160206A: MAXI/GSC detection
  16. Konus-Wind observation of GRB 160104B
  17. Konus-Wind observation of GRB 160102A
  18. Konus-Wind observation of GRB 160107A
  19. GRB 160107A: CALET Gamma-Ray Burst Monitor detection
  20. GRB 160107A: Fermi GBM observation
  21. GRB 160107A: MAXI/GSC detection
  22. Konus-Wind observation of GRB 160101A
  23. GRB 160104B: MAXI/GSC detection
  24. GRB 160102A: Swift-XRT observations
  25. GRB 160102A: Tiled Swift observations
  26. GRB 160102A: MAXI/GSC detection
  27. GRB 160101A: Swift/UVOT Detection
  28. GRB 160101A: Fermi GBM observation
  29. GRB 160101A: Swift-XRT afterglow detection
  30. GRB 160101A: Tiled Swift observations
  31. GRB 160101A: MAXI/GSC detection
  32. LIGO/Virgo G211117: MAXI/GSC observations
  33. GRB 151212A iTelescope observation
  34. GRB 151216A: MAXI/GSC detection
  35. GRB151212A: Swift/UVOT observations
  36. GRB 151212A: GROND Optical Afterglow Candidate
  37. GRB 151212A: Swift-XRT afterglow detection
  38. GRB 151212A: Tiled Swift observations
  39. GRB 151212A: MAXI/GSC detection
  40. GRB 151205C: Optical follow-up observations at Kiso
  41. GRB 151205C: Swift-XRT observations
  42. GRB 151205C: Tiled Swift observations
  43. GRB 151205C: MAXI/GSC detection
  44. GRB 151112A: MAXI/GSC detection
  45. LIGO/Virgo G194575: MAXI/GSC further analysis
  46. GRB 151027A: MAXI/GSC detection
  47. LIGO/Virgo G194575: MAXI/GSC observations
  48. GRB 150907A: Swift-XRT afterglow detection
  49. GRB150907A: Swift/UVOT observations
  50. GRB 150907A: Swift-XRT observations
  51. GRB 150907A: Tiled Swift observations
  52. GRB 150907A: MAXI/GSC detection
  53. GRB 150801A: Swift-XRT observations
  54. GRB 150801A: Tiled Swift observations
  55. GRB 150801A: MAXI/GSC detection
  56. Konus-Wind observation of GRB 150725A
  57. GRB 150725A: MAXI/GSC detection
  58. GRB 150622A: Swift-XRT afterglow detection
  59. V404 Cyg activity (Swift, Fermi, INTGRAL, KONUS, MAXI detection): optical observations in TSHAO, Khureltogot, and AAO
  60. GRB 150622A: Swift-XRT observations
  61. GRB 150622A: Tiled Swift observations
  62. GRB 150622A: MAXI/GSC detection
  63. V404 Cyg: Swift/UVOT Detection
  64. GRB 150608A: Swift-XRT follow-up observations
  65. Konus-Wind observation of GRB 150608A
  66. GRB 150608A: Swift-XRT afterglow detection
  67. GRB 150608A: Tiled Swift observations
  68. GRB 150608A: MAXI/GSC detection
  69. GRB 150518A: possible SN observations
  70. GRB 150518A: MAXI-GSC further analysis
  71. GRB 150518A: Mondy optical observations
  72. GRB 150518A: AMI 15 GHz detection of possible radio counterpart
  73. GRB 150518A: MASTER-net before, early and after optical stereoscopic observations with possible MP discovery inside MAXI error box
  74. Konus-Wind observation of GRB 150518A
  75. GRB 150518A: Swift-XRT follow-up observations
  76. GRB 150518A: Correction
  77. GRB 150518A: VLT/X-shooter redshift of the likely host galaxy
  78. Swift/UVOT observations of GRB150518A
  79. GRB 150518A: Swift-XRT afterglow detection
  80. GRB 150518A: Tiled Swift observations
  81. GRB 150518A: MAXI/GSC detection
  82. Konus-Wind observation of GRB 150430A
  83. GRB 150430A: Fermi GBM Detection
  84. GRB 150430A: MAXI/GSC detection
  85. GRB 150428C: Swift-XRT observations
  86. GRB 150428C: Tiled Swift observations
  87. GRB 150428C/MAXI J0400+678: MAXI/GSC detection
  88. GRB 150424B: Fermi GBM detection
  89. GRB 150424B: Tiled Swift observations
  90. GRB 150424B: MAXI/GSC detection
  91. Konus-Wind observation of GRB 150418A
  92. GRB150418A: Swift/UVOT did not detect a new source
  93. GRB 150418A: Swift-XRT observations
  94. GRB 150418A: Tiled Swift observations
  95. GRB 150418A: MAXI/GSC detection
  96. GRB 150413A: MAXI/GSC detection
  97. GRB 150313A: MAXI/GSC detection
  98. GRB 150311A: Konus-Wind trigger at 16:16:24 is not a GRB
  99. GRB 150311A: MAXI/GSC possible afterglow detection
  100. GRB 150222B: MAXI/GSC detection

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