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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"

3050 results found.

  1. GRB 170510A: Swift-XRT observations
  2. Swift XRT observations of GRB 170424A
  3. LIGO/Virgo G284239: Fermi-LAT search for a high-energy gamma-ray counterpart
  4. GRB 170428A: Swift-XRT refined Analysis
  5. GRB 170419A: Swift-XRT refined Analysis
  6. Swift trigger 748858: Swift BAT, XRT, and UVOT refined analysis
  7. GRB 170405A: Swift-XRT refined Analysis
  8. GRB 170405A: Fermi-LAT detection
  9. IceCube-170321A: Swift-XRT observations
  10. GRB 170330A: Swift-XRT refined Analysis
  11. GRB 170331A: Swift-XRT refined Analysis
  12. GRB 170329A: Fermi-LAT detection
  13. INTEGRAL pointed follow-up of IceCube-170321A
  14. LIGO/Virgo G277583: INTEGRAL search for an X-ray and gamma-ray counterpart
  15. GRB 170318B: Swift-XRT refined Analysis
  16. GRB 170318A: Swift-XRT refined Analysis
  17. GRB 170317A: MITSuME Okayama Ks-band upper-limit
  18. GRB 170317A: Swift-XRT refined Analysis
  19. IceCube-170312A: Swift-XRT observations
  20. LIGO/Virgo G275697: Fermi-LAT search for a high-energy gamma-ray counterpart
  21. GRB 170311A: Swift-XRT refined Analysis
  22. LIGO/Virgo G275404 and AGL J1914+1043: INTEGRAL follow-up
  23. GRB 170306B: Swift-XRT observations
  24. GRB 170306A: Swift-XRT refined Analysis
  25. LIGO/Virgo G275697: Further Swift-XRT sources
  26. GRB170305A: Fermi GBM detection
  27. LIGO/Virgo G275697: Further Swift-XRT sources
  28. LIGO/Virgo G275697: Further Swift-XRT sources
  29. LIGO/Virgo G275697: Further Swift-XRT sources
  30. LIGO/Virgo G275697: Fermi-LAT search for a high-energy gamma-ray counterpart
  31. LIGO/Virgo G275697: Swift-XRT sources
  32. LIGO/Virgo G275404: Fermi-LAT search for a high-energy gamma-ray counterpart
  33. LIGO/Virgo G275404: Swift-XRT sources
  34. GRB 170222A: Swift-XRT observations
  35. LIGO/Virgo G274296: Fermi-LAT search for a high-energy gamma-ray counterpart
  36. GRB 170214A: Swift-XRT afterglow detection
  37. GRB 170214A: Swift-XRT observations
  38. GRB 170208B: IRSF upper limits
  39. GRB 170208A: IRSF upper limits
  40. GRB 170209A: Swift-XRT observations
  41. GRB 170208A: Swift-XRT refined Analysis
  42. GRB 170208B: Swift-XRT refined Analysis
  43. GRB 170206B: Swift-XRT refined Analysis
  44. GRB 170205A: Swift-XRT refined Analysis
  45. GRB 170202A: Swift-XRT refined Analysis
  46. GRB 170202A: Kanata optical and infrared observations
  47. GRB 170131A: Swift-XRT observations
  48. GRB 170127C: Swift-XRT observations
  49. GRB 170127B: Swift-XRT refined Analysis
  50. GRB 170127A: Swift-XRT refined Analysis
  51. GRB 170126A: Swift-XRT refined Analysis
  52. GRB 170121B: Swift-XRT and UVOT observations
  53. LIGO/Virgo G270580: Fermi-LAT search for a high-energy gamma-ray counterpart
  54. LIGO/Virgo G270580: Swift-XRT sources
  55. GRB 170117A: Swift-XRT observations
  56. GRB 170115B: Swift-XRT observations
  57. LIGO/Virgo G268556: Swift-XRT observations of iPTF17cw
  58. GRB 170115A: Swift-XRT refined Analysis
  59. GRB 170113A: Swift-XRT refined Analysis
  60. GRB 170112A: Swift-XRT observations
  61. GRB 170111A: Swift-XRT refined Analysis
  62. LIGO/Virgo G268556: Swift-XRT confirms that ATLAS17aeu is fading in X-rays
  63. Swift Trigger 730874 is not astrophysical
  64. LIGO/Virgo G268556: Swift-XRT detection of ATLAS17aeu
  65. LIGO/Virgo G268556: Fermi-LAT search for high-energy gamma-ray counterpart
  66. LIGO/Virgo G268556: Swift-XRT sources
  67. GRB 161224A: Swift-XRT refined Analysis
  68. GRB 161220A: Swift-XRT refined Analysis
  69. GRB 161219B: Swift-XRT refined Analysis
  70. GRB 161217A: Swift-XRT refined Analysis
  71. GRB 161214B: Swift-XRT refined Analysis
  72. GRB 161202A: Swift-XRT refined Analysis
  73. GRB 161129A: MITSuME Okayama Ks-band Observation
  74. GRB 161129A: Swift-XRT refined Analysis
  75. GRB 161123A: Swift-XRT observations
  76. GRB 161117B: Swift-XRT refined Analysis
  77. GRB 161117A: Swift-XRT refined Analysis
  78. GRB 161113A: Swift-XRT refined Analysis
  79. GRB 161109A: Swift/UVOT Upper Limits
  80. GRB 161104A: Chandra X-ray observations
  81. GRB 161109A: Swift-XRT observations
  82. GRB 161105A: Swift/UVOT Upper Limits
  83. GRB 161108A: Swift-XRT refined Analysis
  84. GRB 161105A: Swift-XRT refined Analysis
  85. GRB 161104A: Swift-XRT refined Analysis
  86. IceCube-161103: Swift-XRT observations
  87. GRB 161023A: Swift-XRT afterglow detection
  88. GRB 161022A: Swift-XRT refined Analysis
  89. GRB 161015A: further Swift-XRT follow-up observations
  90. GRB 161017A: Swift-XRT refined Analysis
  91. GRB 161015A: Swift/UVOT observations
  92. GRB 161015A: Swift-XRT observations
  93. GRB 161014A: Swift-XRT refined Analysis
  94. GRB 161014A: Swift/UVOT Detection
  95. GRB 161014A: Swift-XRT and UVOT afterglow detection
  96. GRB 161011A: Swift-XRT refined Analysis
  97. GRB 161010A: Swift-XRT afterglow detection
  98. GRB 161007A: Swift-XRT refined Analysis
  99. GRB 161001A: IRSF upper limits
  100. GRB 161004B: Swift-XRT refined Analysis

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