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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.

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subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

913 results found.

  1. GRB 160107A: MAXI/GSC detection
  2. Konus-Wind observation of GRB 160101A
  3. GRB 160104B: MAXI/GSC detection
  4. GRB 160102A: Swift-XRT observations
  5. GRB 160102A: Tiled Swift observations
  6. GRB 160102A: MAXI/GSC detection
  7. GRB 160101A: Swift/UVOT Detection
  8. GRB 160101A: Fermi GBM observation
  9. GRB 160101A: Swift-XRT afterglow detection
  10. GRB 160101A: Tiled Swift observations
  11. GRB 160101A: MAXI/GSC detection
  12. LIGO/Virgo G211117: MAXI/GSC observations
  13. Trigger 668877: Swift detection of V 404 Cyg
  14. GRB 151212A iTelescope observation
  15. GRB 151216A: MAXI/GSC detection
  16. GRB151212A: Swift/UVOT observations
  17. GRB 151212A: GROND Optical Afterglow Candidate
  18. GRB 151212A: Swift-XRT afterglow detection
  19. GRB 151212A: Tiled Swift observations
  20. GRB 151212A: MAXI/GSC detection
  21. GRB 151205C: Optical follow-up observations at Kiso
  22. GRB 151205C: Swift-XRT observations
  23. GRB 151205C: Tiled Swift observations
  24. GRB 151205C: MAXI/GSC detection
  25. GRB 151112A: MAXI/GSC detection
  26. Swift-BAT trigger 663164 is not a burst.
  27. LIGO/Virgo G194575: MAXI/GSC further analysis
  28. GRB 151027A: MAXI/GSC detection
  29. LIGO/Virgo G194575: MAXI/GSC observations
  30. Konus-Wind observation of GRB 151006A
  31. GRB 151001B: Swift-XRT refined Analysis
  32. Konus-Wind observation of GRB 150922A
  33. GRB 150907A: Swift-XRT afterglow detection
  34. GRB150907A: Swift/UVOT observations
  35. GRB 150907A: Swift-XRT observations
  36. GRB 150907A: Tiled Swift observations
  37. GRB 150907A: MAXI/GSC detection
  38. GRB 150811A: LCOGT-McDonald afterglow detection
  39. GRB 150801A: Swift-XRT observations
  40. GRB 150801A: Tiled Swift observations
  41. GRB 150801A: MAXI/GSC detection
  42. Konus-Wind observation of GRB 150725A
  43. GRB 150725A: MAXI/GSC detection
  44. GRB 150622A: Swift-XRT afterglow detection
  45. V404 Cyg activity (Swift, Fermi, INTGRAL, KONUS, MAXI detection): optical observations in TSHAO, Khureltogot, and AAO
  46. GRB 150622A: Swift-XRT observations
  47. GRB 150622A: Tiled Swift observations
  48. GRB 150622A: MAXI/GSC detection
  49. GRB 150608A: Swift-XRT follow-up observations
  50. Konus-Wind observation of GRB 150608A
  51. GRB 150608A: Swift-XRT afterglow detection
  52. GRB 150608A: Tiled Swift observations
  53. GRB 150608A: MAXI/GSC detection
  54. GRB 150518A: possible SN observations
  55. GRB 150518A: MAXI-GSC further analysis
  56. GRB 150518A: Mondy optical observations
  57. GRB 150518A: AMI 15 GHz detection of possible radio counterpart
  58. GRB 150518A: MASTER-net before, early and after optical stereoscopic observations with possible MP discovery inside MAXI error box
  59. Konus-Wind observation of GRB 150518A
  60. GRB 150518A: Swift-XRT follow-up observations
  61. GRB 150518A: Correction
  62. GRB 150518A: VLT/X-shooter redshift of the likely host galaxy
  63. Swift/UVOT observations of GRB150518A
  64. GRB 150518A: Swift-XRT afterglow detection
  65. GRB 150518A: Tiled Swift observations
  66. GRB 150518A: MAXI/GSC detection
  67. Konus-Wind observation of GRB 150430A
  68. GRB 150430A: Fermi GBM Detection
  69. GRB 150430A: MAXI/GSC detection
  70. GRB 150428C: Swift-XRT observations
  71. GRB 150428A: MASTER-net early optical observation
  72. GRB 150428C: Tiled Swift observations
  73. GRB 150428C/MAXI J0400+678: MAXI/GSC detection
  74. GRB 150424B: Fermi GBM detection
  75. GRB 150424B: Tiled Swift observations
  76. GRB 150424B: MAXI/GSC detection
  77. Konus-Wind observation of GRB 150418A
  78. GRB150418A: Swift/UVOT did not detect a new source
  79. GRB 150418A: Swift-XRT observations
  80. GRB 150418A: Tiled Swift observations
  81. GRB 150418A: MAXI/GSC detection
  82. GRB 150413A: MAXI/GSC detection
  83. GRB 150413A: MASTER very bright unusual OT observations
  84. GRB 150413A: MASTER bright OT detection
  85. GRB 150313A: MAXI/GSC detection
  86. GRB 150311A: Konus-Wind trigger at 16:16:24 is not a GRB
  87. GRB 150311A: MAXI/GSC possible afterglow detection
  88. GRB 150222B: MAXI/GSC detection
  89. Konus-Wind observation of GRB 150206A
  90. Trigger 630047: Swift detection of 1RXS J180408.9-342058
  91. GRB 150206A: MAXI/GSC detection
  92. GRB 150123A: MASTER inspection
  93. Konus-Wind observation of GRB 150126A reveals its ultra-long nature
  94. GRB 150126A: Fermi GBM Detection
  95. GRB 150126A: MAXI/GSC afterglow candidate detection
  96. Konus-Wind observation of GRB 150123A
  97. GRB 150123A: Swift/UVOT observations
  98. GRB 150123A: Swift-XRT observations
  99. GRB 150123A Tiled Swift observations
  100. GRB 150123A: MAXI/GSC detection

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