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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"

788 results found.

  1. LIGO/Virgo G275697: MAXI/GSC observations
  2. LIGO/Virgo G274296 and G275404 : MAXI/GSC observations
  3. LIGO/Virgo G270580: MAXI/GSC observations
  4. LIGO/Virgo G268556/GW170104: MAXI/GSC observations
  5. Trigger 731183: Swift detection of GRS 1716-249/GRO J1719-24/V2293 Oph
  6. GRS 1716-249/GRO J1719-24/V2293 Oph, Swift-BAT refined analysis
  7. IceCube-161210: MAXI/GSC non-detection
  8. GRB 161123A: Swift-XRT observations
  9. GRB 161123A: Tiled Swift observations
  10. GRB 161123A: MAXI/GSC detection
  11. Konus-Wind observation of GRB 160814A
  12. GRB 160814A: MAXI/GSC detection
  13. SGR 1935+2154: CALET Gamma-Ray Burst Monitor detections
  14. GRB 160705A/MAXI J0748-149: MAXI/GSC detection
  15. More FERMI GBM bursts from the magnetar SGR 1935+2154
  16. SGR 1935+2154: MAXI/GSC detection
  17. Konus-Wind observation of GRB 160509A
  18. GRB 160509A: DCT Imaging / Afterglow Confirmation
  19. GRB 160509A: MAXI/GSC refined analysis
  20. GRB 160509A: Fermi GBM Detection
  21. GRB 160509A: optical observations
  22. Correction to GCN 19404; GRB 160509A: MAXI/GSC detection
  23. GRB 160227A: MAXI/GSC detection
  24. GRB 160227A: MAXI/GSC detection
  25. LIGO/Virgo G184098: MAXI/GSC search for an X-ray counterpart of GW150914
  26. GRB 160206A: Swift/UVOT observations
  27. GRB 160206A: Swift-XRT observations
  28. GRB 160206A: Tiled Swift observations
  29. GRB 160206A: MAXI/GSC detection
  30. Konus-Wind observation of GRB 160104B
  31. Konus-Wind observation of GRB 160102A
  32. Konus-Wind observation of GRB 160107A
  33. GRB 160107A: CALET Gamma-Ray Burst Monitor detection
  34. GRB 160107A: Fermi GBM observation
  35. GRB 160107A: MAXI/GSC detection
  36. Konus-Wind observation of GRB 160101A
  37. GRB 160104B: MAXI/GSC detection
  38. GRB 160102A: Swift-XRT observations
  39. GRB 160102A: Tiled Swift observations
  40. GRB 160102A: MAXI/GSC detection
  41. GRB 160101A: Swift/UVOT Detection
  42. GRB 160101A: Fermi GBM observation
  43. GRB 160101A: Swift-XRT afterglow detection
  44. GRB 160101A: Tiled Swift observations
  45. GRB 160101A: MAXI/GSC detection
  46. LIGO/Virgo G211117: MAXI/GSC observations
  47. GRB 151212A iTelescope observation
  48. GRB 151216A: MAXI/GSC detection
  49. GRB151212A: Swift/UVOT observations
  50. GRB 151212A: GROND Optical Afterglow Candidate
  51. GRB 151212A: Swift-XRT afterglow detection
  52. GRB 151212A: Tiled Swift observations
  53. GRB 151212A: MAXI/GSC detection
  54. GRB 151205C: Optical follow-up observations at Kiso
  55. GRB 151205C: Swift-XRT observations
  56. GRB 151205C: Tiled Swift observations
  57. GRB 151205C: MAXI/GSC detection
  58. GRB 151112A: MAXI/GSC detection
  59. LIGO/Virgo G194575: MAXI/GSC further analysis
  60. GRB 151027A: MAXI/GSC detection
  61. LIGO/Virgo G194575: MAXI/GSC observations
  62. GRB 150907A: Swift-XRT afterglow detection
  63. GRB150907A: Swift/UVOT observations
  64. GRB 150907A: Swift-XRT observations
  65. GRB 150907A: Tiled Swift observations
  66. GRB 150907A: MAXI/GSC detection
  67. GRB 150801A: Swift-XRT observations
  68. GRB 150801A: Tiled Swift observations
  69. GRB 150801A: MAXI/GSC detection
  70. Konus-Wind observation of GRB 150725A
  71. GRB 150725A: MAXI/GSC detection
  72. GRB 150622A: Swift-XRT afterglow detection
  73. V404 Cyg activity (Swift, Fermi, INTGRAL, KONUS, MAXI detection): optical observations in TSHAO, Khureltogot, and AAO
  74. GRB 150622A: Swift-XRT observations
  75. GRB 150622A: Tiled Swift observations
  76. GRB 150622A: MAXI/GSC detection
  77. GRB 150608A: Swift-XRT follow-up observations
  78. Konus-Wind observation of GRB 150608A
  79. GRB 150608A: Swift-XRT afterglow detection
  80. GRB 150608A: Tiled Swift observations
  81. GRB 150608A: MAXI/GSC detection
  82. GRB 150518A: possible SN observations
  83. GRB 150518A: MAXI-GSC further analysis
  84. GRB 150518A: Mondy optical observations
  85. GRB 150518A: AMI 15 GHz detection of possible radio counterpart
  86. GRB 150518A: MASTER-net before, early and after optical stereoscopic observations with possible MP discovery inside MAXI error box
  87. Konus-Wind observation of GRB 150518A
  88. GRB 150518A: Swift-XRT follow-up observations
  89. GRB 150518A: Correction
  90. GRB 150518A: VLT/X-shooter redshift of the likely host galaxy
  91. Swift/UVOT observations of GRB150518A
  92. GRB 150518A: Swift-XRT afterglow detection
  93. GRB 150518A: Tiled Swift observations
  94. GRB 150518A: MAXI/GSC detection
  95. Konus-Wind observation of GRB 150430A
  96. GRB 150430A: Fermi GBM Detection
  97. GRB 150430A: MAXI/GSC detection
  98. GRB 150428C: Swift-XRT observations
  99. GRB 150428C: Tiled Swift observations
  100. GRB 150428C/MAXI J0400+678: MAXI/GSC detection

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