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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').

2808 results found.

  1. GRB 220618A: Swift-XRT refined Analysis
  2. GRB 220617A: Swift-XRT observations
  3. GRB 220611A: Gemini Ks counterpart detection
  4. GRB 220611A: Gemini South Infrared Detection
  5. GRB 220611A: Swift-XRT refined Analysis
  6. GRB 220606B: Swift follow-up observations
  7. GRB 220527A: Swift/UVOT detection
  8. GRB 220527A: Swift-XRT afterglow detection
  9. Fermi GRB 220523A: Global MASTER-Net observations report
  10. GRB 220521A: Swift-XRT refined Analysis
  11. GRB 220518A: Swift-XRT refined Analysis
  12. Continued Chandra monitoring of GW170817 at ~4.8 yr post-merger
  13. GRB 220514B: Swift-XRT observations
  14. GRB 220511A: Swift-XRT afterglow detection
  15. GRB 220511A: Swift-XRT observations
  16. GRB 220506A: Swift-XRT afterglow detection
  17. GRB 220430A: Swift-XRT refined Analysis
  18. GRB 220426A: Swift-XRT and UVOT observations
  19. GRB 220427A: Swift-XRT refined Analysis
  20. GRB 220418B: Swift-XRT observations
  21. GRB 220403C: Further Swift-XRT observations
  22. GRB 220412B: Swift-XRT observations
  23. GRB 220412A: Swift-XRT refined Analysis
  24. GRB 220403C: Swift-XRT observations
  25. GRB 220408A: Swift-XRT refined Analysis
  26. Chandra upper limit at the location of GRB 220408A
  27. GRB 220403B: Swift-XRT refined Analysis
  28. GRB 220325A: Swift-XRT refined Analysis
  29. GRB 220319A: Swift-XRT refined Analysis
  30. GRB 220310C: Swift-XRT observations
  31. GRB 220306B: Swift-XRT refined Analysis
  32. GRB 220305A: Swift-XRT refined Analysis
  33. GRB 220302A: Swift-XRT refined Analysis
  34. GRB 220219B: Swift-XRT observations
  35. ZTF22aaajecp/AT2022cmc: Swift Observation and a UV Detection
  36. ZTF22aabjpxh/AT2022cva: NICER X-ray detection is consistent with a GRB afterglow
  37. IceCube-220205B - IceCube observation of a high-energy neutrino candidate track-like event
  38. GRB 220117B: Swift-XRT refined Analysis
  39. GRB 220117A: Swift-XRT refined Analysis
  40. Confirmation of the X-ray afterglow of GRB 220107B
  41. GRB 220107A: Swift/UVOT Detection
  42. GRB 220107B: Swift-XRT afterglow detection
  43. GRB 220107A: Swift-XRT afterglow detection
  44. GRB 220101A: Swift-XRT refined Analysis
  45. GRB 211229A: Swift-XRT and UVOT observations
  46. Fermi GRB 211229B: Global MASTER-Net observations report
  47. GRB 211227A: Swift-XRT refined Analysis
  48. GRB 211221A: Swift-XRT refined Analysis
  49. GRB 211106A: XMM-Newton monitoring campaign detections
  50. GRB 211211A: Swift-XRT refined Analysis
  51. Chandra observation of GW170817 at ~1573 days since merger (Epoch 1 of 4)
  52. GRB 211207A: Swift-XRT refined Analysis
  53. GRB 211129A: Swift-XRT refined Analysis
  54. Chandra observations of GRB 210905A
  55. GRB 211106A: Swift/UVOT upper limits
  56. GRB 211107B: Swift-XRT afterglow detection
  57. GRB 211106A: Swift-XRT afterglow detection
  58. GRB 211107B: Swift-XRT observations
  59. GRB 211106A: Swift-XRT observations
  60. Swift Trigger 1082569 is probably not a GRB
  61. GRB 211024A: Swift-XRT observations
  62. GRB 211018A: Swift-XRT observations
  63. GRB 211025A: Swift-XRT refined Analysis
  64. GRB 211024B: CAHA 2.2m Detection; ultra-long GRB?
  65. GRB 211024B: Swift-XRT refined Analysis
  66. GRB 211023B: Swift-XRT refined Analysis
  67. GRB 210928A: Swift-XRT analysis (replaces GCN 30914)
  68. GRB 210928A: Swift-XRT refined Analysis
  69. GRB 210930A: Swift/UVOT Upper Limits
  70. GRB 210930A: Swift-XRT refined Analysis
  71. GRB 210919A: Swift-XRT refined Analysis
  72. GRB 210912A: Swift-XRT refined Analysis
  73. GRB 210826A: further Swift-XRT observations
  74. Fermi trigger No 652927551: Global MASTER-Net observations report
  75. GRB 210905A: Swift-XRT refined Analysis
  76. GRB 210901A: Swift-XRT refined Analysis
  77. GRB 210827A: further Swift-XRT observations
  78. GRB 210827A: Swift-XRT observations
  79. GRB 210826A: Swift-XRT observations
  80. GRB 210826A: Fermi-LAT detection
  81. GRB 210824A: Swift-XRT refined Analysis
  82. GRB 210822A: Swift-XRT refined Analysis
  83. GRB 210820A: Swift-XRT refined Analysis
  84. GRB 210818A: Swift-XRT refined Analysis
  85. GRB 210802A: Further Swift/XRT observation and afterglow confirmation
  86. GRB 210807C: Swift-XRT refined Analysis
  87. GRB 210807A: Swift-XRT refined Analysis
  88. GRB 210802A: Swift-XRT afterglow detection
  89. GRB 210731A: Swift-XRT refined Analysis
  90. GRB 210726A: Chandra detection of the X-ray afterglow
  91. GRB 210730A: Swift-XRT refined Analysis
  92. GRB 210726A: Swift-XRT refined Analysis
  93. GRB 210725B: Swift-XRT refined Analysis
  94. GRB 210725A: Swift-XRT refined Analysis
  95. GRB 210724A: Swift-XRT refined Analysis
  96. GRB 210723A: Swift-XRT refined Analysis
  97. GRB 210722A: Swift-XRT refined Analysis
  98. GRB 210712A: Swift-XRT refined Analysis
  99. GRB 210706A: Swift/XRT afterglow confirmation
  100. GRB 210708A: Swift-XRT refined Analysis

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