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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"

19611 results found.

  1. IPN Triangulation of GRB 151229B (extremely intense/long)
  2. LIGO/Virgo G211117: Swift observations of PS15dpn
  3. IPN Triangulation of GRB 151225A (short/hard)
  4. LIGO/Virgo G211117: Further Swift-XRT sources
  5. GRB 160104A: Nishi-Harima MINT Observations
  6. GRB 160104A: Swift-XRT refined Analysis
  7. GRB 160104A: Swift-BAT refined analysis
  8. GRB 160104A: Fermi GBM observation
  9. GRB 160104A: Mini-GWAC upper limit during prompt emission phase
  10. GRB 160104A: GWAC upper limit during prompt emission phase
  11. GRB 160104A: Enhanced Swift-XRT position
  12. GRB 160104A: LCOGT-FTN afterglow candidate
  13. GRB 160104A: Swift detection of a burst
  14. GRB 160102A: Swift-XRT observations
  15. GRB 160101A: MITSuME Akeno optical upper limits
  16. GRB 160102A: Tiled Swift observations
  17. GRB 160101A: Swift/UVOT Detection
  18. GRB 160101A: Fermi GBM observation
  19. GRB 160101A: Swift-XRT afterglow detection
  20. GRB 160101A: Tiled Swift observations
  21. Trigger 668949: Swift detection of V 404 Cyg
  22. MASTER-NET observations of V404Cyg Swift Trigger 668877
  23. Trigger 668879: Swift detection of V 404 Cyg again
  24. Trigger 668877: Swift detection of V 404 Cyg
  25. IPN Triangulation of GRB 151227B
  26. GRB 151228A: Correction to GCN 18770
  27. GRB 151228A: Swift-XRT refined Analysis
  28. V404Cyg Swift Trigger 668097: CrAO RT-22 radio observations
  29. V404Cyg Swift Trigger 668097: AbAO optical observations
  30. GRB 151228B: Swift/UVOT Detection
  31. GRB 151229A Swift-BAT Spectral lag analysis
  32. GRB 151228B: MITSuME Akeno optical upper limits
  33. GRB 151229A: Swift-XRT refined Analysis
  34. GRB 151229A: Fermi GBM observation
  35. GRB 151228B: Fermi GBM observation
  36. GRB 151228A: Swift-BAT refined analysis
  37. GRB 151229A: Swift/UVOT observations
  38. GRB 151228B: Swift-BAT refined analysis
  39. GRB 151229A: Swift-BAT refined analysis
  40. GRB 151229A: Enhanced Swift-XRT position
  41. GRB 151228B: Swift-XRT refined Analysis
  42. LIGO/Virgo G211117: Further Swift-XRT sources
  43. GRB 151229A: Swift detection of a short burst
  44. GRB 151228B: Enhanced Swift-XRT position
  45. GRB 151228B: Swift detection of a burst with an optical detection
  46. GRB 151228A: Fermi GBM observation
  47. LIGO/Virgo G211117: Further Swift-XRT sources
  48. LIGO/Virgo G211117: Swift-XRT sources
  49. GRB 151228A: Swift detection of a short burst
  50. V404Cyg Swift Trigger 668097: TSHAO optical observations
  51. V404Cyg Swift Trigger 668097: MASTER-Tunka optical wake up detection
  52. V404Cyg Swift Trigger 668097:
  53. Trigger 668097: Swift detection of V 404 Cyg
  54. GRB151215A: Continued P60 Observations
  55. GRB 151215A: MITSuME Akeno optical upper limits
  56. GRB 151215A: Swift-XRT refined Analysis
  57. GRB 151215A: Swift-BAT refined analysis
  58. GRB151215A: Swift/UVOT detection
  59. GRB 151215A: Enhanced Swift-XRT position
  60. GRB 151215A: GROND Detection of the Optical/NIR Afterglow
  61. GRB 151215A: Prompt enhanced Swift-XRT position
  62. GRB 151215A: Swift detection of a burst
  63. GRB151212A: Swift/UVOT observations
  64. GRB 151212A: GROND Optical Afterglow Candidate
  65. GRB 151212A: Swift-XRT afterglow detection
  66. GRB 151212A: Tiled Swift observations
  67. GRB 151210A: Swift/UVOT Upper Limits
  68. GRB 151210A: Swift-BAT refined analysis
  69. GRB 151210A: Swift-XRT refined Analysis
  70. GRB 151210A: Enhanced Swift-XRT position
  71. GRB 151210A: GROND Afterglow Confirmation
  72. GRB 151210A: Swift detection of a burst
  73. GRB 151205A: Khureltogot upper limit
  74. Swift detection of 4U 1850-03
  75. GRB 151205B: Deep GROND Upper limits
  76. GRB 130831A: MASTER early OT detection and LC
  77. GRB 151205B: further Swift-XRT observations
  78. GRB 151205C: Swift-XRT observations
  79. GRB 151205B, Swift-BAT refined analysis
  80. GRB 151205A: Swift-XRT refined Analysis
  81. GRB 151205A, Swift-BAT refined analysis
  82. GRB 151205C: Tiled Swift observations
  83. GRB 151205B: MASTER-NET early optical observations
  84. GRB 151205A: Fermi GBM detection
  85. GRB 151205A: Garching Telescope Upper Limit
  86. GRB151205B: Initial UVOT observations
  87. GRB 151205B: Swift-XRT observations
  88. GRB 151205A: Swift/UVOT Upper Limits
  89. GRB 151205B: Swift detection of a burst
  90. GRB 151205A: Enhanced Swift-XRT position
  91. GRB 151205A: Swift detection of a burst
  92. GRB 151127A iTelescope observation
  93. GRB 151122A: Further Swift-XRT observations, no afterglow detected.
  94. GRB 151127A: Swift/UVOT Upper Limits
  95. GRB 151127A: Swift-XRT refined Analysis
  96. GRB 151127A: Swift-BAT refined analysis
  97. GRB 151127A: Enhanced Swift-XRT position
  98. GRB 151127A: GROND K-band upper limit
  99. GRB 151127A: Swift detection of a short burst
  100. GRB 151118A iTelescope observation

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