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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"

6667 results found.

  1. GRB 180613A: Swift-XRT refined Analysis
  2. GRB 180611A: Fermi GBM observation
  3. GRB 180605A: Fermi GBM observation
  4. GRB 180602B: Fermi GBM detection
  5. GRB 180602A: Swift-XRT refined Analysis
  6. GRB 180514A: Swift/UVOT Upper Limits
  7. GRB 180514A: 1.5m OSN optical observations
  8. GRB 180514A: Swift-XRT refined Analysis
  9. GRB 180512A: Swift-XRT refined Analysis
  10. GRB 180510B: Swift-XRT refined Analysis
  11. GRB 180510A: Swift-XRT refined Analysis
  12. Chandra observations of GW170817 reveal a fading afterglow
  13. Chandra observations of GW170817 260 days since merger: first statistically significant evidence for an X-ray decay
  14. GRB 180505A: Fermi GBM detection
  15. GRB 180504A: Swift-XRT refined Analysis
  16. Konus-Wind observation of GRB 180427A
  17. GRB 180427A: Fermi GBM detection
  18. GRB 180425A: Swift-XRT refined Analysis
  19. GRB 180418A: Xinglong TNT optical upper limit
  20. GRB 180418A: Fermi GBM observation
  21. GRB 180418A: Swift-XRT refined Analysis
  22. LIGO/Virgo G299232: LOFAR follow-up
  23. GRB 180416A: Fermi GBM detection
  24. GRB 180409A: Swift-XRT afterglow detection
  25. GRB 180411B: CALET Gamma-Ray Burst Monitor detection
  26. GRB 180410A: Fermi GBM observation
  27. GRB 180411A: Fermi GBM detection
  28. GRB 180411A: Swift-XRT refined Analysis
  29. GRB 180410A: Swift-XRT refined Analysis
  30. GRB 180409A: Fermi GBM observation
  31. GRB 180409A: Swift-XRT observations
  32. Chandra observations of GRB161219B 400 days after the explosion
  33. GRB 180404A: Swift-XRT refined Analysis
  34. GRB 180404B: Swift-XRT refined Analysis
  35. GRB 180404B: Fermi GBM observation
  36. GRB 180402A: Swift-XRT refined Analysis
  37. GRB 180331B: Swift-XRT refined Analysis
  38. GRB 180331A: Swift-XRT refined Analysis
  39. GRB 180329B: NOT optical afterglow detection
  40. GRB 180329B: Swift-XRT refined Analysis
  41. GRB 180325A: Swift-XRT refined Analysis
  42. GRB 180324A: Swift-XRT refined Analysis
  43. GRB 180316A: Swift-XRT refined Analysis
  44. GRB 180314B: Swift-XRT refined Analysis
  45. GRB 180313A: Fermi GBM detection
  46. GRB 180314A: Swift-XRT refined Analysis
  47. GRB 180314A: Fermi GBM observation
  48. GRB 180311A: Swift-XRT refined Analysis
  49. GRB 180305A: Swift-XRT afterglow detection
  50. GRB 180305A: Fermi GBM detection
  51. GRB 180305A: Fermi-LAT detection
  52. GRB 180224A: Swift-XRT refined Analysis
  53. GRB 180222A: Swift-XRT refined Analysis
  54. Swift trigger 811074 (possible GRB 180221A): Swift refined analysis
  55. GRB 180218A: Fermi GBM Detection
  56. Swift J1658.2-4242: Swift BAT and XRT refined analysis
  57. Swift J1658.2-4242 (trigger 810300): Swift-XRT position
  58. GRB 180210A: Swift-XRT afterglow detection
  59. GRB 180205A: BAO optical observations
  60. GRB 180210A: Fermi-LAT detection
  61. GRB 180210A: Fermi GBM detection
  62. GRB 180205A: Swift-XRT refined Analysis
  63. GRB 180205A: Xinglong TNT optical observation
  64. GRB 180205A: Fermi GBM observation
  65. GRB 180204A: Fermi GBM detection
  66. GRB 180204A: Swift-XRT refined Analysis
  67. GW170817/GRB170817A: Updated results from the full Chandra dataset
  68. LIGO/Virgo GW170817: Chandra X-ray Emission Continues to Rise ~156 Days Post-Merger
  69. GRB 180120A: Fermi GBM Detection
  70. GRB 180116A CALET Gamma-Ray Burst Monitor detection
  71. GRB 180116A: Fermi GBM Detection
  72. GRB 180115A: Swift-XRT refined Analysis
  73. GRB 180113C: Fermi GBM detection
  74. GRB 180113B: Fermi GBM detection
  75. GRB 180113A: Fermi GBM observation
  76. GRB 180103A: Swift-XRT afterglow detection
  77. GRB 180111A: Swift-XRT refined Analysis
  78. GRB180111A: Xinglong TNT possible optical detection
  79. GRB 180103A: Swift/UVOT Upper Limits
  80. GRB 180103A: Swift-XRT observations
  81. GRB 180102A: Swift-XRT refined Analysis
  82. GRB 180102A: Fermi GBM detection
  83. GRB 171227A: Fermi GBM detection
  84. IceCube-171106A: Konus-Wind upper limits
  85. IceCube-171015A: Konus-Wind upper limits
  86. IceCube-170922A: Konus-Wind upper limits
  87. GRB 171223A: Fermi GBM detection
  88. GRB 171222A: Fermi GBM detection
  89. GRB 171222A: Swift-XRT refined Analysis
  90. GRB 171210A: Further Swift-XRT observations
  91. GRB 171216A: Swift-XRT refined Analysis
  92. GRB 171212A: Swift-XRT refined Analysis
  93. GRB 171212B: Fermi GBM observation
  94. GRB 171212B: Fermi-LAT detection
  95. GRB 171211A: Swift-XRT refined Analysis
  96. GRB 171210A: Swift-XRT and UVOT observations
  97. GRB 171210A: Fermi GBM detection
  98. GRB 171210A: Fermi-LAT detection
  99. GRB 171205A: SAO-RAS optical observations
  100. Swift trigger 796115 is not astrophysical

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