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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"

18434 results found.

  1. GRB 120815A: Swift-XRT observations
  2. GRB 120815A: TAROT La Silla observatory optical observations
  3. GRB 120815A: Swift detection of a burst
  4. GRB 120804A: Possible temporal break in the X-ray light-curve
  5. GCN for GRB 120811C
  6. GRB 120811A: Swift/XRT-UVOT Obseravations
  7. GRB120804A: Chandra observations and afterglow detection
  8. GRB 120805A: Enhanced Swift-XRT position
  9. GRB 120811C: EVLA Observations
  10. GRB 120811C: RTT150 optical observations
  11. GRB 120811C: MASTER-Tunka OT observations
  12. GRB 120811C: Swift-BAT refined analysis
  13. GRB 120811A: Swift-BAT refined analysis
  14. GRB 120811C: Bassano Bresciano Observatory optical observations
  15. GRB 120811C: Swift-XRT refined Analysis
  16. GRB 120811C: Swift/UVOT Detection
  17. Improved IPN error box for short hard GRB 120811B
  18. GRB 120811C: RTT150 optical observations
  19. GRB 120811C: Enhanced Swift-XRT position
  20. GRB 120811C: TAROT Calern observatory optical observations
  21. GRB 120811C: Swift detection of a burst with an optical counterpart
  22. IPN Triangulation of short hard GRB 120811B
  23. Trigger 530588: Swift detection of XMM J174457-2850.3
  24. Swift Trigger 530581: GRB 120811A or a galactic transient
  25. GRB 120803A: optical upper limit
  26. GRB 120807A: Swift/UVOT Upper Limits
  27. GRB 120803A: Confirmation of the X-ray afterglow
  28. GRB 120804A: Konus-Wind and Swift/BAT joint spectral analysis
  29. Swift Trigger 530441 is a false trigger
  30. GRB 120807A: Swift-XRT refined Analysis
  31. GRB 120807A: Fermi/LAT upper limit
  32. GRB 120807A: RAPTOR Limits During Gamma-Ray Emitting Interval
  33. GRB 120807A: TAROT La Silla observatory optical observations
  34. GRB 120807A: Swift-BAT refined analysis
  35. GRB 120807A: Enhanced Swift-XRT position
  36. GRB 120807A: Swift detection of a burst
  37. Fermi/GBM detection of an SGR-like burst
  38. Swift-BAT trigger 530214 is noise
  39. GRB 120805A: Swift/UVOT Upper Limits
  40. Swift trigger 530214: uncertain if real or not
  41. Swift-BAT trigger 529813 is due to noise while entering the SAA
  42. GRB 120728A: Fermi GBM observation
  43. GRB 120805A: Swift-BAT refined analysis
  44. GRB 120802A: Swift/UVOT Upper Limits
  45. GRB 120805A: Swift-XRT refined Analysis
  46. GRB120805A: Liverpool Telescope observations
  47. GRB 120805A: TAROT Calern observatory optical observations
  48. GRB 120805A: Swift detection of a burst
  49. GRB 120804A: EVLA Detection
  50. GRB 120804A: Swift-BAT Spectral lag analysis
  51. GRB 120803B: Swift-XRT refined Analysis
  52. GRB 120804A: Swift/UVOT Upper Limits
  53. GRB 120804A: Swift-BAT refined analysis
  54. GRB 120804A: Swift-XRT refined Analysis
  55. GRB 120804A: GROND upper limits
  56. GRB 120802A: EVLA Observations
  57. GRB 120804A: Enhanced Swift-XRT position
  58. GRB 120804A: Swift detection of a short burst
  59. GRB 120803B: Swift-BAT refined analysis
  60. GRB 120803B: Enhanced Swift-XRT position
  61. GRB 120803A: Swift-XRT Observations
  62. GRB 120803A: Swift-BAT refined analysis
  63. GRB 120803B: Swift detection of a burst
  64. GRB 120803A: Swift detection of a possible burst
  65. GRB 120802A: GRT Optical Observation
  66. GRB 120802A: Swift-XRT refined Analysis
  67. GRB 120729A: Fermi GBM observation
  68. GRB 120802A: Swift-BAT refined analysis
  69. GRB 120802A: Enhanced Swift-XRT position
  70. GRB 120802A: MASTER optical observations
  71. GRB 120802A: Swift detection of a burst
  72. GRB 120729A: RTT150 optical observations
  73. GRB 120729A: EVLA Observations
  74. GRB 120729A: Early RAPTOR Observations
  75. GRB 120728A: GROND Afterglow discovery
  76. GRB 120729A: Swift-XRT refined Analysis
  77. Correction to Swift GCN Circular 13538
  78. GRB 120729A: Swift/UVOT Detection
  79. Swift Trigger 529076 is from Swift J1910.2-0546 and is not a GRB
  80. GRB 120729A, Swift-BAT refined analysis
  81. GRB 120728A, Swift-BAT refined analysis
  82. GRB 120729A: Enhanced Swift-XRT position
  83. GRB 120728A: Swift/UVOT Upper Limits
  84. GRB120729A - Faulkes Telescope North Optical Afterglow Candidate
  85. GRB 120729A: Swift detection of a burst with an optical afterglow
  86. GRB 120728A: Swift-XRT refined Analysis
  87. GRB 120728A: Enhanced Swift-XRT position
  88. Trigger 529076: Swift possible detection of SwJ1910.2-0546
  89. GRB 120728A: GROND observations
  90. GRB 120728A: Swift detection of a burst
  91. Swift Trigger 528925 is probably a noise fluctuation
  92. GRB 120722A: optical upper limit
  93. GRB 120724A: optical observation in Maidanak observatory
  94. GRB 120724A, Swift-BAT refined analysis
  95. GRB 120724A: Swift/UVOT Detection of the Optical Afterglow
  96. GRB 120724A: Enhanced Swift-XRT position
  97. GRB 120724A: Swift-XRT refined Analysis
  98. GRB 120724A: Swift detection of a burst
  99. GRB 120709A: Swift re-observation of the field of the X-ray counterpart candidate.
  100. GRB 120722A: Swift/UVOT Upper Limits

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