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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"

6098 results found.

  1. GRB 180715A: Swift-XRT observations
  2. IceCube-170922A: First Optical observations of the Neutrino Trigger by MASTER Global Net and 25 IceCube alerts inspection.
  3. GRB 180705A: OSN observations
  4. GRB 180709A: Swift-XRT refined Analysis
  5. GRB 180703B: further analysis of CGBM data
  6. GRB 180703A: Swift-XRT afterglow detection
  7. GRB 180705A: Swift-XRT refined Analysis
  8. GRB 180706A: Fermi GBM observation
  9. GRB 180706A: Swift-XRT refined Analysis
  10. GRB 180703B: Fermi GBM detection
  11. GRB 180703A: Fermi GBM detection
  12. GRB 180704A: Swift-XRT refined Analysis
  13. GRB 180703A: Swift-XRT observations
  14. GRB 180703B: Fermi-LAT detection
  15. GRB 180703A: Fermi-LAT detection
  16. GRB 180630A: Swift/UVOT Detection
  17. GRB 180630A: Swift-XRT refined Analysis
  18. GRB 180630A: Fermi GBM detection
  19. GRB 180626A: Swift-XRT refined Analysis
  20. GRB 180624A: Swift-XRT refined Analysis
  21. GRB 180623A: Swift-XRT refined Analysis
  22. Konus-Wind observation of GRB 180618A (a short GRB with extended emission)
  23. GRB 180613A: Afterglow confirmation and added photometry
  24. GRB 180620B: Swift-XRT refined Analysis
  25. GRB 180620B: Fermi GBM detection
  26. GRB 180620A: Swift-XRT refined Analysis
  27. GRB 180618A: Fermi GBM detection
  28. GRB 180618A: Swift-XRT refined Analysis
  29. GRB 180614A: Swift/UVOT Upper Limits
  30. GRB 180614A: Swift-XRT refined Analysis
  31. GRB 180613A: Possible IR afterglow
  32. GRB 180613A: Swift-XRT refined Analysis
  33. GRB 180611A: Fermi GBM observation
  34. GRB 180605A: Fermi GBM observation
  35. GRB 180602B: Fermi GBM detection
  36. GRB 180602A: Swift-XRT refined Analysis
  37. GRB 180514A: Swift/UVOT Upper Limits
  38. GRB 180514A: 1.5m OSN optical observations
  39. GRB 180514A: Swift-XRT refined Analysis
  40. GRB 180512A: Swift-XRT refined Analysis
  41. GRB 180510B: Swift-XRT refined Analysis
  42. GRB 180510A: Swift-XRT refined Analysis
  43. Chandra observations of GW170817 reveal a fading afterglow
  44. Chandra observations of GW170817 260 days since merger: first statistically significant evidence for an X-ray decay
  45. GRB 180505A: Fermi GBM detection
  46. GRB 180504A: Swift-XRT refined Analysis
  47. Konus-Wind observation of GRB 180427A
  48. GRB 180427A: Fermi GBM detection
  49. GRB 180425A: Swift-XRT refined Analysis
  50. GRB 180418A: Xinglong TNT optical upper limit
  51. GRB 180418A: Fermi GBM observation
  52. GRB 180418A: Swift-XRT refined Analysis
  53. LIGO/Virgo G299232: LOFAR follow-up
  54. GRB 180416A: Fermi GBM detection
  55. GRB 180409A: Swift-XRT afterglow detection
  56. GRB 180411B: CALET Gamma-Ray Burst Monitor detection
  57. GRB 180410A: Fermi GBM observation
  58. GRB 180411A: Fermi GBM detection
  59. GRB 180411A: Swift-XRT refined Analysis
  60. GRB 180410A: Swift-XRT refined Analysis
  61. GRB 180409A: Fermi GBM observation
  62. GRB 180409A: Swift-XRT observations
  63. Chandra observations of GRB161219B 400 days after the explosion
  64. GRB 180404A: Swift-XRT refined Analysis
  65. GRB 180404B: Swift-XRT refined Analysis
  66. GRB 180404B: Fermi GBM observation
  67. GRB 180402A: Swift-XRT refined Analysis
  68. GRB 180331B: Swift-XRT refined Analysis
  69. GRB 180331A: Swift-XRT refined Analysis
  70. GRB 180329B: NOT optical afterglow detection
  71. GRB 180329B: Swift-XRT refined Analysis
  72. GRB 180325A: Swift-XRT refined Analysis
  73. GRB 180324A: Swift-XRT refined Analysis
  74. GRB 180316A: Swift-XRT refined Analysis
  75. GRB 180314B: Swift-XRT refined Analysis
  76. GRB 180313A: Fermi GBM detection
  77. GRB 180314A: Swift-XRT refined Analysis
  78. GRB 180314A: Fermi GBM observation
  79. GRB 180311A: Swift-XRT refined Analysis
  80. GRB 180305A: Swift-XRT afterglow detection
  81. GRB 180305A: Fermi GBM detection
  82. GRB 180305A: Fermi-LAT detection
  83. GRB 180224A: Swift-XRT refined Analysis
  84. GRB 180222A: Swift-XRT refined Analysis
  85. Swift trigger 811074 (possible GRB 180221A): Swift refined analysis
  86. GRB 180218A: Fermi GBM Detection
  87. Swift J1658.2-4242: Swift BAT and XRT refined analysis
  88. Swift J1658.2-4242 (trigger 810300): Swift-XRT position
  89. GRB 180210A: Swift-XRT afterglow detection
  90. GRB 180205A: BAO optical observations
  91. GRB 180210A: Fermi-LAT detection
  92. GRB 180210A: Fermi GBM detection
  93. GRB 180205A: Swift-XRT refined Analysis
  94. GRB 180205A: Xinglong TNT optical observation
  95. GRB 180205A: Fermi GBM observation
  96. GRB 180204A: Fermi GBM detection
  97. GRB 180204A: Swift-XRT refined Analysis
  98. GW170817/GRB170817A: Updated results from the full Chandra dataset
  99. LIGO/Virgo GW170817: Chandra X-ray Emission Continues to Rise ~156 Days Post-Merger
  100. GRB 180120A: Fermi GBM Detection

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