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GCN Circulars

GCN Circulars are rapid bulletins submitted by and distributed to the community. 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"

3408 results found.

  1. LIGO/Virgo G298048: Possible Plateau in Ks band revealed by continued Gemini-South observations
  2. LIGO/Virgo G298048: Continued Gemini South observations
  3. LIGO/Virgo G298048: Discovery of X-ray emission from SSS17a in NGC4993
  4. LIGO/Virgo G299232: Further Swift/UVOT Observations of Optical Transient SwiftJ014008.5+343403.6
  5. LIGO/Virgo G299232: Optical Transient Discovery by Swift/UVOT
  6. LIGO/Virgo G298936: HAWC follow-up
  7. GRB 170827A: Swift-XRT refined Analysis
  8. LIGO/Virgo G299232/PGWB170825.55: MASTER Global-Net OT inside NGC1343 discovery
  9. LIGO/Virgo G299232 : Fermi-LAT search for high-energy gamma-ray counterpart
  10. LIGO/Virgo G298389: HAWC follow-up
  11. LIGO/Virgo G297595: INTEGRAL pointed follow-up observations
  12. LIGO/Virgo G298048: INTEGRAL pointed follow-up observations
  13. LIGO/Virgo G298936 : Fermi-LAT search for a high-energy gamma-ray counterpart
  14. GRB 170822A: Swift-XRT refined Analysis
  15. LIGO/Virgo G298389 : Fermi-LAT search for a high-energy gamma-ray counterpart
  16. LIGO/Virgo G298048: Possible X-ray detection with Swift
  17. LIGO/Virgo G298048: optical spectral energy distribution of SSS17a
  18. LIGO/VIRGO G298048: Swift UVOT detection and XRT upper limits
  19. LIGO/Virgo G297595: Swift-XRT sources
  20. LIGO/Virgo G297595 : Fermi-LAT search for high-energy gamma-ray counterpart
  21. GRB 170813A: Swift/UVOT Upper Limits
  22. GRB 170813A: Swift-XRT refined Analysis
  23. GRB 170810A: Swift-XRT refined Analysis
  24. LIGO/Virgo G296853: Fermi-LAT search for high-energy gamma-ray counterpart
  25. GRB 170804A: Swift-XRT refined Analysis
  26. Swift Trigger 766161 is not a GRB
  27. GRB 170803A: Swift-XRT refined Analysis
  28. GRB 170714A: Chandra observations
  29. GRB 170728A: Swift-XRT refined Analysis
  30. GRB 170728B: Swift-XRT refined Analysis
  31. GRB 170714A: Bastille Day Burst: ULGRB or RTDE?
  32. GRB 170714A: Swift-XRT refined Analysis
  33. GRB 170711A: Swift-XRT refined Analysis
  34. GRB 170710B: Fermi GBM observation
  35. GRB 170710B: Swift-XRT and UVOT observations
  36. GRB 170710A: Swift-XRT refined Analysis
  37. GRB 170705A: Swift-XRT refined Analysis
  38. GRB 170629A: Swift-XRT refined Analysis
  39. GRB 170626A: Swift-XRT refined Analysis
  40. LIGO/Virgo G288732: Kiso/KWFC optical imaging of the possible Fermi/LAT counterpart
  41. LIGO/Virgo G288732: Swift/UVOT follow up of the possible LAT counterpart
  42. LIGO/Virgo G288732: Swift-XRT follow up of the putative LAT counterpart
  43. LIGO/Virgo G288732: Fermi-LAT detection of a weak candidate
  44. GRB 170607A: Swift-XRT refined Analysis
  45. Swift trigger 755873: Swift BAT and XRT refined analysis
  46. GRB 170522A: confirmation of the X-ray afterglow
  47. GRB 170604A: Swift-XRT refined Analysis
  48. GRB 170531B: Swift-XRT refined Analysis
  49. GRB 170531A: Swift-XRT refined Analysis
  50. GRB 170524B: Swift-UVOT/XRT Confirmation of Afterglow
  51. GRB 170526A: Swift-XRT refined Analysis
  52. GRB 170524B: Swift-XRT observations
  53. GRB 170524A: Swift-XRT refined Analysis
  54. GRB 170522A: Swift-XRT observations
  55. GRB 170519A: KAIT Optical Observations
  56. GRB 170519A: Swift-XRT refined Analysis
  57. GRB 170510A: Swift-XRT afterglow detection
  58. GRB 170516A: Swift-XRT refined Analysis
  59. GRB 170510A: Swift-XRT observations
  60. Swift XRT observations of GRB 170424A
  61. LIGO/Virgo G284239: Fermi-LAT search for a high-energy gamma-ray counterpart
  62. GRB 170428A: Swift-XRT refined Analysis
  63. GRB 170419A: Swift-XRT refined Analysis
  64. Swift trigger 748858: Swift BAT, XRT, and UVOT refined analysis
  65. GRB 170405A: Swift-XRT refined Analysis
  66. GRB 170405A: Fermi-LAT detection
  67. IceCube-170321A: Swift-XRT observations
  68. GRB 170330A: Swift-XRT refined Analysis
  69. GRB 170331A: Swift-XRT refined Analysis
  70. GRB 170329A: Fermi-LAT detection
  71. INTEGRAL pointed follow-up of IceCube-170321A
  72. LIGO/Virgo G277583: INTEGRAL search for an X-ray and gamma-ray counterpart
  73. GRB 170318B: Swift-XRT refined Analysis
  74. GRB 170318A: Swift-XRT refined Analysis
  75. GRB 170317A: MITSuME Okayama Ks-band upper-limit
  76. GRB 170317A: Swift-XRT refined Analysis
  77. IceCube-170312A: Swift-XRT observations
  78. LIGO/Virgo G275697: Fermi-LAT search for a high-energy gamma-ray counterpart
  79. GRB 170311A: Swift-XRT refined Analysis
  80. LIGO/Virgo G275404 and AGL J1914+1043: INTEGRAL follow-up
  81. GRB 170306B: Swift-XRT observations
  82. GRB 170306A: Swift-XRT refined Analysis
  83. LIGO/Virgo G275697: Further Swift-XRT sources
  84. GRB170305A: Fermi GBM detection
  85. LIGO/Virgo G275697: Further Swift-XRT sources
  86. LIGO/Virgo G275697: Further Swift-XRT sources
  87. LIGO/Virgo G275697: Further Swift-XRT sources
  88. LIGO/Virgo G275697: Fermi-LAT search for a high-energy gamma-ray counterpart
  89. LIGO/Virgo G275697: Swift-XRT sources
  90. LIGO/Virgo G275404: Fermi-LAT search for a high-energy gamma-ray counterpart
  91. LIGO/Virgo G275404: Swift-XRT sources
  92. GRB 170222A: Swift-XRT observations
  93. LIGO/Virgo G274296: Fermi-LAT search for a high-energy gamma-ray counterpart
  94. GRB 170214A: Swift-XRT afterglow detection
  95. GRB 170214A: Swift-XRT observations
  96. GRB 170208B: IRSF upper limits
  97. GRB 170208A: IRSF upper limits
  98. GRB 170209A: Swift-XRT observations
  99. GRB 170208A: Swift-XRT refined Analysis
  100. GRB 170208B: Swift-XRT refined Analysis

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