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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"

18432 results found.

  1. GRB 120722A: Swift-BAT refined analysis
  2. GRB 120722A: Enhanced Swift-XRT position
  3. GRB 120722A: Swift detection of a burst
  4. GRB 120716A: EVLA Detection
  5. GRB 120716A: Swift-XRT detection
  6. GRB 120716A: Swift/XRT position consistent with that of the optical counterpart
  7. GRB 120716A: GROND confirmation of the optical/NIR afterglow
  8. GRB 120714B: Swift/UVOT Detection
  9. GRB 120714B: Swift-XRT refined Analysis
  10. GRB120714A: Swift/UVOT upper limits
  11. GRB 120714B: Swift-BAT refined analysis
  12. Swift-BAT refined analysis of 1E 1841-045 (Trigger=526660)
  13. GRB 120714A: GROND upper limits
  14. GRB 120714B: GROND confirmation of fading afterglow
  15. GRB 120714A: Swift-XRT refined Analysis
  16. Trigger 526660: Swift detection of 1 E 1841-045 (aka Kes 73)
  17. GRB 120714B: Position Correction and Candidate Optical Afterglow
  18. GRB 120714A: Swift-BAT refined analysis
  19. GRB 120714B: Swift detection of a burst
  20. GRB 120714A: Enhanced Swift-XRT position
  21. GRB 120712A: Fermi GBM observation
  22. GRB120714A: UVOT non-detection
  23. GRB 120714A: Swift-XRT observations
  24. GRB 120714A: Swift detection of a burst
  25. IPN Triangulation of GRB 120709A
  26. GRB 120712A: Swift/UVOT Detection
  27. GRB 120712A: Swift-XRT refined Analysis
  28. GRB 120712A: GROND Detection of the Optical/NIR Afterglow Candidate and photo-z
  29. GRB 120712A: Enhanced Swift-XRT position
  30. GRB 120712A: Swift-BAT refined analysis
  31. GRB 120712A: Swift detection of a burst with optical afterglow
  32. GRB 120711B: Swift-XRT refined Analysis
  33. GRB 120711B: Swift-BAT refined analysis
  34. GRB 120711B: Swift/UVOT Upper Limits
  35. GRB 120711A: Swift/UVOT Observations
  36. GRB 120709A: Swift/UVOT Observations
  37. GRB 120711A: Fermi LAT detection
  38. GRB 120711A: Swift-XRT observations
  39. Swift detection of GRB 120711B or a new Galactic transient
  40. GRB 120709A: Swift-XRT observations
  41. IPN Triangulation of GRB 120707A
  42. GRB 120709A: Fermi-LAT Detection
  43. GRB 120703A: Swift/UVOT Detection
  44. GRB 120703A: Fermi GBM detection
  45. GRB 120703A: Swift-XRT refined Analysis
  46. GRB 120703A: Enhanced Swift-XRT position
  47. GRB 120703A: Swift-BAT refined analysis
  48. GRB 120624B Suzaku WAM observation of the prompt emission
  49. Konus-Wind observation of GRB 120703A
  50. GRB 120701A: Swift/UVOT Detection
  51. GRB 120701A: GROND detection of the afterglow
  52. GRB 120703A: Swift detection of a bright burst with an optical afterglow
  53. Swift Trigger 525554 is noise
  54. GRB 120701A: Swift-XRT afterglow detection and analysis
  55. GRB 120630A: Swift-BAT/-XRT/-UVOT refined analysis
  56. GRB 120701A: Swift-BAT refined analysis
  57. GRB 120630A: NOT optical source within the XRT error circle
  58. Swift Trigger 525554 is probably not a GRB
  59. GRB120624B: Chandra observations and afterglow detection
  60. GRB 120624B Further Swift-XRT analysis
  61. GRB 120624B: Swift/UVOT Upper Limits
  62. Watcher follow-up observations of IGR J17062-6143 (Swift trigger 525148)
  63. GRB 120624B: Swift-XRT observations
  64. GRB 120624B: GROND upper limits
  65. GRB 120624B: NIR counterpart candidate from HAWKI
  66. Skynet/PROMPT observations of IGR J17062-6143 (Swift trigger 525148)
  67. GRB 120624B: Discussion of Fermi and Swift measurements and future Swift observations
  68. Swift detection of Ginga 0834-430
  69. GRB 120624B: NOT optical upper limit
  70. Swift detection of IGR J17062-6143
  71. GRB 120624B: optical observations
  72. GRB 120624B, Swift-BAT refined analysis
  73. GRB 120624B: Swift detection of a burst
  74. GRB 120624B: Fermi-LAT Detection
  75. IPN Triangulation of GRB 120624A (short/intense)
  76. Swift Trigger 524949: Noise fluctuation near a galaxy
  77. Swift trigger 524642 / SwJ1910.2-0546
  78. GRB 120602A: Suzaku WAM observation of the prompt emission
  79. Swift Trigger 524642 is Swift J1910.2-0546
  80. Trigger 524584: Swift detection of Algol
  81. Swift triggers (#524542) on a Galactic source
  82. IPN Triangulation of GRB 120602A (long/very bright)
  83. GRB 120612A: Swift/UVOT observations
  84. GRB 120612A: Swift-XRT refined Analysis
  85. GRB 120612A: Swift-BAT refined analysis
  86. GRB 120612A: Enhanced Swift-XRT position
  87. GRB 120612A: BOOTES-3 optical upper limit
  88. GRB 120612A: Swift detection of a burst
  89. GRB 120603A: Suzaku WAM observation of the prompt emission
  90. GRB 120519A: Suzaku WAM observation of the prompt emission
  91. GRB 120512A: Suzaku WAM observation of the prompt emission
  92. GRB 120521C: EVLA Localization of Afterglow
  93. GRB 120521C: EVLA 22 GHz Detection
  94. GRB 120521B: Fermi GBM observation
  95. GRB 120521C: Early Tautenburg limits
  96. GRB 120521C: EVLA 22 GHz Upper Limit
  97. GRB 120521A: GROND Upper limits
  98. GRB 120521C: Swift-XRT refined Analysis
  99. GRB 120521C: Swift-BAT refined analysis
  100. GRB 120521C: Swift/UVOT Upper Limits

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