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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"

19666 results found.

  1. GRB 160127A: VLA Detection
  2. GRB 160127A: Swift/UVOT Detection
  3. GRB 160127A: Swift-BAT refined analysis
  4. GRB 160127A: Swift-XRT refined Analysis
  5. GRB 160123A: TAROT La Silla observatory optical observations
  6. GRB 160127A: Enhanced Swift-XRT position
  7. GRB 160127A: TAROT La Silla observatory optical light curve
  8. GRB 160127A: Swift detection of a burst with an optical counterpart
  9. GRB 160123A: GROND Upper limits
  10. GRB 160121A: TSHAO optical observation
  11. GRB 160123A: Swift/UVOT Upper Limits
  12. GRB 160123A: Swift-XRT refined Analysis
  13. GRB 160123A: Swift-BAT refined analysis
  14. GRB 160123A: Enhanced Swift-XRT position
  15. GRB 160123A: Swift detection of a burst
  16. GRB 160121A: RATIR Optical Observations
  17. GRB 160121A: Swift-XRT refined Analysis
  18. GRB 160121A: Swift/UVOT Upper Limits
  19. GRB 160121A: GROND Afterglow observations
  20. GRB 160121A: TSHAO optical afterglow confirmation
  21. GRB 160121A: Swift-BAT refined analysis
  22. GRB 160121A: Enhanced Swift-XRT position
  23. GRB 160121A: 1.8m MOA optical afterglow detection
  24. GRB 160121A: MASTER-Amur observations
  25. GRB 160121A: Swift detection of a burst
  26. Konus-Wind observation of GRB 160119A
  27. GRB 160117A: Swift-XRT afterglow detection
  28. GRB 160119A: VLA Detection
  29. GRB 160117B: VLA Detection
  30. GRB160119A: BOOTES-2/TELMA Early Upper Limits
  31. GRB 160119A: Swift/UVOT Upper Limits
  32. GRB 160119A: GROND optical/NIR afterglow observations
  33. GRB 160117B: RATIR Optical and NIR Observations
  34. GRB 160119A: Swift-BAT refined analysis
  35. GRB 160119A: Swift-XRT refined Analysis
  36. GRB 160119A: Enhanced Swift-XRT position
  37. GRB 160119A: Swift detection of a burst
  38. GRB 160117A: Swift/UVOT Upper Limits
  39. GRB 151228B: AbAO optical upper limit
  40. GRB 160117A: Swift-XRT observations
  41. GRB 160117B: Swift-XRT refined Analysis
  42. GRB 160117A: Swift-BAT refined analysis
  43. GRB 160117B: Swift/UVOT Detection
  44. GRB 160117B: Enhanced Swift-XRT position
  45. GRB 160117B: LCOGT-SSO optical observations
  46. GRB 160117B: Swift detection of a burst with optical counterpart
  47. GRB 160117A: Swift detection of a burst
  48. IPN Triangulation of GRB 160113A
  49. LIGO/Virgo G211117: Further Swift-XRT sources
  50. IPN Triangulation of GRB 160111A (short/hard)
  51. GRB 160113A: Swift-XRT observations
  52. GRB 160113A: Swift ToO observations
  53. GRB 160113A: iPTF P48 Observations and Optical Transient Candidates
  54. GRB 160104A: Swift/UVOT Detection
  55. IPN Triangulation of GRB 151231A
  56. IPN Triangulation of GRB 151229B (extremely intense/long)
  57. LIGO/Virgo G211117: Swift observations of PS15dpn
  58. IPN Triangulation of GRB 151225A (short/hard)
  59. LIGO/Virgo G211117: Further Swift-XRT sources
  60. GRB 160104A: Nishi-Harima MINT Observations
  61. GRB 160104A: Swift-XRT refined Analysis
  62. GRB 160104A: Swift-BAT refined analysis
  63. GRB 160104A: Fermi GBM observation
  64. GRB 160104A: Mini-GWAC upper limit during prompt emission phase
  65. GRB 160104A: GWAC upper limit during prompt emission phase
  66. GRB 160104A: Enhanced Swift-XRT position
  67. GRB 160104A: LCOGT-FTN afterglow candidate
  68. GRB 160104A: Swift detection of a burst
  69. GRB 160102A: Swift-XRT observations
  70. GRB 160101A: MITSuME Akeno optical upper limits
  71. GRB 160102A: Tiled Swift observations
  72. GRB 160101A: Swift/UVOT Detection
  73. GRB 160101A: Fermi GBM observation
  74. GRB 160101A: Swift-XRT afterglow detection
  75. GRB 160101A: Tiled Swift observations
  76. Trigger 668949: Swift detection of V 404 Cyg
  77. MASTER-NET observations of V404Cyg Swift Trigger 668877
  78. Trigger 668879: Swift detection of V 404 Cyg again
  79. Trigger 668877: Swift detection of V 404 Cyg
  80. IPN Triangulation of GRB 151227B
  81. GRB 151228A: Correction to GCN 18770
  82. GRB 151228A: Swift-XRT refined Analysis
  83. V404Cyg Swift Trigger 668097: CrAO RT-22 radio observations
  84. V404Cyg Swift Trigger 668097: AbAO optical observations
  85. GRB 151228B: Swift/UVOT Detection
  86. GRB 151229A Swift-BAT Spectral lag analysis
  87. GRB 151228B: MITSuME Akeno optical upper limits
  88. GRB 151229A: Swift-XRT refined Analysis
  89. GRB 151229A: Fermi GBM observation
  90. GRB 151228B: Fermi GBM observation
  91. GRB 151228A: Swift-BAT refined analysis
  92. GRB 151229A: Swift/UVOT observations
  93. GRB 151228B: Swift-BAT refined analysis
  94. GRB 151229A: Swift-BAT refined analysis
  95. GRB 151229A: Enhanced Swift-XRT position
  96. GRB 151228B: Swift-XRT refined Analysis
  97. LIGO/Virgo G211117: Further Swift-XRT sources
  98. GRB 151229A: Swift detection of a short burst
  99. GRB 151228B: Enhanced Swift-XRT position
  100. GRB 151228B: Swift detection of a burst with an optical detection

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