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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"

3407 results found.

  1. LIGO/Virgo G298048: Continued Gemini South observations
  2. LIGO/Virgo G298048: Discovery of X-ray emission from SSS17a in NGC4993
  3. LIGO/Virgo G299232: Further Swift/UVOT Observations of Optical Transient SwiftJ014008.5+343403.6
  4. LIGO/Virgo G299232: Optical Transient Discovery by Swift/UVOT
  5. LIGO/Virgo G298936: HAWC follow-up
  6. GRB 170827A: Swift-XRT refined Analysis
  7. LIGO/Virgo G299232/PGWB170825.55: MASTER Global-Net OT inside NGC1343 discovery
  8. LIGO/Virgo G299232 : Fermi-LAT search for high-energy gamma-ray counterpart
  9. LIGO/Virgo G298389: HAWC follow-up
  10. LIGO/Virgo G297595: INTEGRAL pointed follow-up observations
  11. LIGO/Virgo G298048: INTEGRAL pointed follow-up observations
  12. LIGO/Virgo G298936 : Fermi-LAT search for a high-energy gamma-ray counterpart
  13. GRB 170822A: Swift-XRT refined Analysis
  14. LIGO/Virgo G298389 : Fermi-LAT search for a high-energy gamma-ray counterpart
  15. LIGO/Virgo G298048: Possible X-ray detection with Swift
  16. LIGO/Virgo G298048: optical spectral energy distribution of SSS17a
  17. LIGO/VIRGO G298048: Swift UVOT detection and XRT upper limits
  18. LIGO/Virgo G297595: Swift-XRT sources
  19. LIGO/Virgo G297595 : Fermi-LAT search for high-energy gamma-ray counterpart
  20. GRB 170813A: Swift/UVOT Upper Limits
  21. GRB 170813A: Swift-XRT refined Analysis
  22. GRB 170810A: Swift-XRT refined Analysis
  23. LIGO/Virgo G296853: Fermi-LAT search for high-energy gamma-ray counterpart
  24. GRB 170804A: Swift-XRT refined Analysis
  25. Swift Trigger 766161 is not a GRB
  26. GRB 170803A: Swift-XRT refined Analysis
  27. GRB 170714A: Chandra observations
  28. GRB 170728A: Swift-XRT refined Analysis
  29. GRB 170728B: Swift-XRT refined Analysis
  30. GRB 170714A: Bastille Day Burst: ULGRB or RTDE?
  31. GRB 170714A: Swift-XRT refined Analysis
  32. GRB 170711A: Swift-XRT refined Analysis
  33. GRB 170710B: Fermi GBM observation
  34. GRB 170710B: Swift-XRT and UVOT observations
  35. GRB 170710A: Swift-XRT refined Analysis
  36. GRB 170705A: Swift-XRT refined Analysis
  37. GRB 170629A: Swift-XRT refined Analysis
  38. GRB 170626A: Swift-XRT refined Analysis
  39. LIGO/Virgo G288732: Kiso/KWFC optical imaging of the possible Fermi/LAT counterpart
  40. LIGO/Virgo G288732: Swift/UVOT follow up of the possible LAT counterpart
  41. LIGO/Virgo G288732: Swift-XRT follow up of the putative LAT counterpart
  42. LIGO/Virgo G288732: Fermi-LAT detection of a weak candidate
  43. GRB 170607A: Swift-XRT refined Analysis
  44. Swift trigger 755873: Swift BAT and XRT refined analysis
  45. GRB 170522A: confirmation of the X-ray afterglow
  46. GRB 170604A: Swift-XRT refined Analysis
  47. GRB 170531B: Swift-XRT refined Analysis
  48. GRB 170531A: Swift-XRT refined Analysis
  49. GRB 170524B: Swift-UVOT/XRT Confirmation of Afterglow
  50. GRB 170526A: Swift-XRT refined Analysis
  51. GRB 170524B: Swift-XRT observations
  52. GRB 170524A: Swift-XRT refined Analysis
  53. GRB 170522A: Swift-XRT observations
  54. GRB 170519A: KAIT Optical Observations
  55. GRB 170519A: Swift-XRT refined Analysis
  56. GRB 170510A: Swift-XRT afterglow detection
  57. GRB 170516A: Swift-XRT refined Analysis
  58. GRB 170510A: Swift-XRT observations
  59. Swift XRT observations of GRB 170424A
  60. LIGO/Virgo G284239: Fermi-LAT search for a high-energy gamma-ray counterpart
  61. GRB 170428A: Swift-XRT refined Analysis
  62. GRB 170419A: Swift-XRT refined Analysis
  63. Swift trigger 748858: Swift BAT, XRT, and UVOT refined analysis
  64. GRB 170405A: Swift-XRT refined Analysis
  65. GRB 170405A: Fermi-LAT detection
  66. IceCube-170321A: Swift-XRT observations
  67. GRB 170330A: Swift-XRT refined Analysis
  68. GRB 170331A: Swift-XRT refined Analysis
  69. GRB 170329A: Fermi-LAT detection
  70. INTEGRAL pointed follow-up of IceCube-170321A
  71. LIGO/Virgo G277583: INTEGRAL search for an X-ray and gamma-ray counterpart
  72. GRB 170318B: Swift-XRT refined Analysis
  73. GRB 170318A: Swift-XRT refined Analysis
  74. GRB 170317A: MITSuME Okayama Ks-band upper-limit
  75. GRB 170317A: Swift-XRT refined Analysis
  76. IceCube-170312A: Swift-XRT observations
  77. LIGO/Virgo G275697: Fermi-LAT search for a high-energy gamma-ray counterpart
  78. GRB 170311A: Swift-XRT refined Analysis
  79. LIGO/Virgo G275404 and AGL J1914+1043: INTEGRAL follow-up
  80. GRB 170306B: Swift-XRT observations
  81. GRB 170306A: Swift-XRT refined Analysis
  82. LIGO/Virgo G275697: Further Swift-XRT sources
  83. GRB170305A: Fermi GBM detection
  84. LIGO/Virgo G275697: Further Swift-XRT sources
  85. LIGO/Virgo G275697: Further Swift-XRT sources
  86. LIGO/Virgo G275697: Further Swift-XRT sources
  87. LIGO/Virgo G275697: Fermi-LAT search for a high-energy gamma-ray counterpart
  88. LIGO/Virgo G275697: Swift-XRT sources
  89. LIGO/Virgo G275404: Fermi-LAT search for a high-energy gamma-ray counterpart
  90. LIGO/Virgo G275404: Swift-XRT sources
  91. GRB 170222A: Swift-XRT observations
  92. LIGO/Virgo G274296: Fermi-LAT search for a high-energy gamma-ray counterpart
  93. GRB 170214A: Swift-XRT afterglow detection
  94. GRB 170214A: Swift-XRT observations
  95. GRB 170208B: IRSF upper limits
  96. GRB 170208A: IRSF upper limits
  97. GRB 170209A: Swift-XRT observations
  98. GRB 170208A: Swift-XRT refined Analysis
  99. GRB 170208B: Swift-XRT refined Analysis
  100. GRB 170206B: Swift-XRT refined Analysis

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