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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"

19607 results found.

  1. GRB 151122A: Swift detection of a burst
  2. GRB 151027A: Maidanak optical observations
  3. Swift-BAT refined analysis of trigger 664624 from SGR J1819-1600
  4. Swift Trigger 664610 is not astrophysical
  5. Swift-BAT probable detection of an outburst from SGR J1819-1600 (AX J1818.8-1559)
  6. Swift Trigger 664610: is unlikely a GRB
  7. GRB 151120A: Swift-XRT afterglow detection
  8. GRB 151118A: AAO optical upper limit
  9. GRB 151120A: Swift ToO observations
  10. GRB 151118A, Swift-BAT refined analysis
  11. 610 MHz detection of GRB 151027A with the GMRT
  12. GRB 151118A: ISON-NM early optical limit
  13. GRB 151118A: Swift-XRT refined Analysis
  14. GRB 151118A: Swift/UVOT Upper Limits
  15. GRB 151118A: Enhanced Swift-XRT position
  16. GRB GRB 151118A: MASTER-NET optical observations
  17. GRB 151118A: Swift detection of a burst
  18. Swift-BAT resumption of normal operations
  19. GMRT radio detection of GRB 151027A
  20. GRB 151114A: GROND Detection of the Optical/NIR Afterglow Candidate
  21. GRB 151114A: Swift-XRT refined Analysis
  22. GRB 151114A: Swift-BAT refined analysis
  23. GRB 151112A: GROND photometric redshift and i'-band prediction
  24. GRB 151114A: Swift/UVOT Detection
  25. GRB 151114A: LCOGT-FTS afterglow observations
  26. GRB 151114A: Enhanced Swift-XRT position
  27. GRB 151114A: Swift detection of a burst with an optical counterpart
  28. GRB 151111A: GROND confirmation of the afterglow and photometric redshift estimate
  29. GRB 151112A: Swift/UVOT Upper Limits
  30. GRB 151112A: MAXI/GSC detection
  31. GRB 151112A: GROND Detection of the Optical/NIR Afterglow Candidate
  32. GRB 151112A: Swift-XRT refined Analysis
  33. GRB 151112A: Swift-BAT refined analysis
  34. GRB 151112A: Enhanced Swift-XRT position
  35. GRB 151112A: MASTER-NET optical limit
  36. GRB 151112A: Swift-XRT observations
  37. GRB 151112A: Swift detection of a burst
  38. GRB 151111A: Swift/UVOT upper limits
  39. Swift-BAT trigger 663164 is not a burst.
  40. GRB 151111A: GROND marginal detection of a afterglow candidate
  41. GRB 151111A: Swift-XRT refined Analysis
  42. GRB 151111A: Fermi GBM observation
  43. GRB 151111A: LCOGT-FTS afterglow observations
  44. GRB 151111A: Swift-BAT refined analysis
  45. GRB 151111A: Enhanced Swift-XRT position
  46. GRB 151111A: Swift detection of a burst
  47. GRB 151027A: continued Mondy optical observations
  48. GRB 151107A: Further investigation of the source nature
  49. LIGO/Virgo G194575: Swift observations if iPTF15dld
  50. GRB 151107A, Swift-BAT refined analysis
  51. GRB 151107A: MASTER-NET optical observations
  52. GRB 151107A: Swift detection of a possible burst
  53. Swift-BAT triggers are disabled
  54. GRB 151027A: Mondy optical observations
  55. GRB 150910A: CrAO optical observations
  56. GRB 151031A: GROND observation
  57. GRB 151027B: ATCA radio detection
  58. GRB 151031A: Swift/UVOT Detection
  59. GRB 151031A: Swift-XRT refined Analysis
  60. GRB 151031A: Swift-BAT refined analysis
  61. GRB 151031A: Enhanced Swift-XRT position
  62. GRB 151031A: Swift detection of a burst
  63. Correction to the Trigger Time for Swift GRB 151029A
  64. GRB 151027A: Optical counterpart detection
  65. GRB 151029A: Swift-XRT refined Analysis
  66. GRB 151029A: Swift/UVOT Detection
  67. GRB 151029A: LCOGT-FTS afterglow observations
  68. GRB 151027B: Swift UVOT detection
  69. GRB 151029A: Swift-BAT refined analysis
  70. GRB 151029A: Enhanced Swift-XRT position
  71. GRB 151027A: MAXI/GSC detection
  72. GRB 151029A: GROND afterglow observations
  73. GRB 151029A: Swift detection of a burst with an optical counterpart
  74. GRB 151027B: LCOGT FTN afterglow observations
  75. GRB 151027A: NOT optical and NIR observations
  76. GRB 151027A: T100 observations
  77. GRB 151027B: Swift/UVOT Upper Limits
  78. Konus-Wind observation of GRB 151027A
  79. GRB 151027B: Swift-BAT refined analysis
  80. GRB 151027B: RATIR Observations
  81. GRB 151027B: MASTER-NET early OT detection
  82. GRB 151027A: LCOGT-McDonald afterglow observations
  83. GRB 151027B: Swift-XRT refined Analysis
  84. GRB 151027A: VLA detection
  85. GRB 151027B: GROND Optical/NIR Afterglow Detection
  86. GRB 151027B: VLT/X-shooter redshift
  87. GRB 151027B: Enhanced Swift-XRT position
  88. GRB 151027A: UVOT Observations
  89. GRB 151027B: NOT optical afterglow candidate
  90. GRB 151027B: Swift detection of its 1000-th burst
  91. GRB 151027A: Swift-BAT refined analysis
  92. GRB 151027A: Early RAPTOR Observations
  93. GRB 151027A: Fermi GBM observation
  94. GRB 151027A: Swift-XRT refined Analysis
  95. LIGO/Virgo G194575: Swift observations of LSQ15bjb
  96. Tentative redshift for GRB 151027A from Swift-XRT data
  97. GRB 151027A: Enhanced Swift-XRT position
  98. GRB 151027A : ISON-NM early optical detection
  99. GRB 151027A: KAIT optical afterglow confirmation
  100. GRB 151027A: Swift detection of a burst with a bright optical afterglow

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