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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"

19197 results found.

  1. GRB 070714A: Swift/UVOT Upper limits
  2. GRB 070714B: Swift/UVOT Upper Limits
  3. GRB 070714B: Swift-BAT spectral lag for the SHB
  4. GRB 070714A: Swift XRT refined analysis
  5. GRB070714B: Swift-XRT refined analysis
  6. GRB 070707: Swift-XRT follow-up observations
  7. GRB 070714B, Swift-BAT refined analysis of the short hard burst
  8. GRB 070714A, Swift-BAT refined analysis
  9. GRB 070714: Swift detection of a bright burst, possibly short
  10. Swift detection of a possible burst (Trigger 284850)
  11. GRB 070704: Suzaku/WAM observation of the prompt emission
  12. Updated Swift/UVOT calibration
  13. GRB 070707: object inside XRT error circle
  14. Swift/UVOT Observations of GRB070707
  15. Swift XRT observation of GRB 070707
  16. GRB070704: FAVOR optical observations
  17. GRB 070704: Swift-XRT refined analysis
  18. Swift/UVOT Observations of GRB070704
  19. GRB 070704, Swift-BAT refined analysis
  20. GRB 070704: Correction to GCN Circ 6594
  21. GRB 070704: Swift detection of a burst
  22. GRB 070628 Swift-UVOT Refined Analysis
  23. GRB 070628: NIR detection of afterglow
  24. GRB 070628, Swift-BAT refined analysis
  25. GRB 070628: TAROT La Silla observatory optical observations
  26. GRB 070628: Swift XRT refined analysis
  27. GRB 070628: Watcher Observations
  28. Swift UVOT Observations of GRB 070628
  29. GRB 070628: Swift detection of a possible burst
  30. INTEGRAL burst GRB070615: X-ray continued observations
  31. GRB 070616 : WIDGET simultaneous optical observations
  32. GRB 070616: Suzaku/WAM observation of the prompt emission
  33. GRB 070621: Swift/UVOT Upper Limits
  34. GRB 070621: Swift-BAT refined analysis
  35. GRB070621: Swift XRT refined analysis
  36. GRB 070621: UVOT-enhanced XRT position
  37. GRB070621: OPTIMA-Burst optical upper limit
  38. GRB 070621: TAROT Calern observatory optical observations
  39. GRB 070621: Watcher Observations
  40. GRB 070621: ROTSE-III Prompt Optical Limits
  41. GRB 070621: Swift detection of a burst
  42. GMRT upper limit of GRB 070610/SWIFT J195509.6+261406 in 610 MHz
  43. Swift/UVOT detection of GRB070616 optical afterglow.
  44. GRB 070616, Swift-BAT further refined analysis
  45. GRB 070616: Swift XRT refined circular
  46. GRB 070616: BTA optical observations
  47. Swift/UVOT observations of GRB070616
  48. GRB 070616: TLS observation
  49. Swift XRT observations of the INTEGRAL burst GRB070615: Possible
  50. GRB 070616, Swift-BAT partial refined analysis
  51. GRB 070616: Swift detection of a burst
  52. UVOT Observations of INTEGRAL burst GRB070615
  53. SWIFT J195509.6+261406 (GRB 070610): further observations
  54. GRB 070612A: Rapid Decay
  55. GRB 070612A: Suzaku/WAM observation of the prompt emission
  56. SWIFT J195509.6+261406 / GRB 070610: OPTIMA-Burst observations
  57. GRB 070611: Watcher Observations
  58. Swift Trigger 282176 is Cygnus X-1
  59. GRB 070612A: MDM Observations
  60. GRB 070612B, Swift-BAT refined analysis
  61. GRB 070612A, Swift-BAT refined analysis
  62. GRB 070612B: Swift-XRT refined analysis
  63. SWIFT J195509.6+261406 / GRB 070610: SWIFT continued observations
  64. GRB 070612B: Swift/UVOT upper limits
  65. GRB 070612B: FRAM limit
  66. GRB 070612B: KAIT limits
  67. GRB 070612B: Swift XRT position from downlink data
  68. GRB 070610: TAROT Calern observatory optical observations
  69. GRB 070612B: Swift detection of a burst
  70. GRB 070612: Swift detection of a burst
  71. GRB 070610: Swift-XRT refined analysis
  72. GRB 070610: TLS RRM sees flaring behaviour - Galactic transient?
  73. GRB 070611: Swift/UVOT Observations
  74. GRB 070611: Swift-XRT refined analysis
  75. GRB 070611, Swift-BAT refined analysis
  76. GRB 070610: Watcher Observations
  77. GRB 070611: ROTSE-III Detection of Late Rising Optical Counterpart
  78. GRB 070611; Swift-XRT position
  79. GRB 070611: ROTSE-III Optical Limits
  80. GRB 070611: Swift detection of a burst
  81. GRB 070610: Swift-UVOT Upper Limits
  82. GRB 070610: OPTIMA-Burst high-time-resolution optical observations
  83. GRB 070610, Swift-BAT refined analysis
  84. GRB 070610; Swift-XRT position
  85. GRB 070610: Swift detection of a burst
  86. GRB 070412: TAROT Calern observatory optical observations
  87. GRB 070411: TAROT Calern observatory optical observations
  88. Swift/UVOT refined analysis of GRB070531
  89. GRB 070531: Swift-BAT refined analysis
  90. GRB 070531: Swift-XRT position
  91. GRB 070531: Liverpool Telescope Optical Observations
  92. GRB 070531: Swift detection of a burst
  93. Swift/UVOT refined analysis of GRB070529
  94. GRB 070529: MARGE Observations
  95. GRB 070529: Optical aterglow from MIRO
  96. GRB 070529: Swift-XRT refined analysis
  97. GRB 070529, Swift-BAT refined analysis
  98. GRB 070529: Swift detection of a burst with an optical aterglow
  99. GRB 070412: Deep Keck imaging
  100. Swift Triggers 280447, 280450 and 280451 are invalid

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