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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"

19189 results found.

  1. Swift UVOT Observations of the X-ray transient in NGC 2770
  2. Early OT detection of XRF in NGC 2770 in Asiago frames
  3. Bright X-ray Transient in NGC 2770 - A low-luminosity XRF?
  4. GRB 071227: Suzaku WAM observation of the prompt emission
  5. Further Swift-BAT analysis of GRB 071227
  6. Konus-Wind observation of GRB 071227
  7. GRB 071227: Swift-XRT refined analysis
  8. GRB071227: Swift/UVOT refined analysis
  9. Swift-BAT refined analysis of short GRB 071227
  10. GRB 071227: Swift detection of a burst
  11. GRB 070429B: Possible UVOT Detection of an Optical Afterglow
  12. Swift-BAT trigger 298308 is not a GRB
  13. GRB 071208?: Swift detection of a possible burst
  14. GRB 071129, Swift-BAT refined analysis
  15. GRB 071129: Swift detection of a burst
  16. GRB 071126: Enhanced Swift-XRT position
  17. VLA radio detection of GRB 071122
  18. GRB071122: Swift/UVOT Observations
  19. GRB 071122, Swift-BAT refined analysis
  20. GRB 071122 Swift XRT position update sent in error.
  21. GRB 071122 Swift-XRT refined analysis
  22. GRB 071122: ROTSE-III Optical Limits
  23. GRB 071122: Swift detection of a burst
  24. Swift/UVOT observations of GRB071118
  25. GRB 071117: Swift-XRT revised position
  26. Konus-Wind and Konus-A observations of GRB 071117
  27. Swift XRT follow-up observations of GRB071008
  28. Swift/UVOT upper limits for GRB 071117
  29. GRB071118: Swift XRT refined analysis
  30. GRB 071118, Swift-BAT refined analysis
  31. GRB 071117: TAROT La Silla observatory optical observations
  32. GRB 071118: Swift detection of a burst
  33. GRB 071117: Swift-XRT refined analysis
  34. GRB 071117, Swift-BAT refined analysis
  35. GRB 071117: Swift/XRT position
  36. GRB 071117: Initial Swift/UVOT observations
  37. GRB 071117: Swift detection of a bright burst
  38. Swift detection of MXB 0656-072
  39. VLA radio upper limit on GRB 071112C
  40. ATCA radio observations of short hard burst GRB 071112B
  41. Correction to the Swift-BAT Transient Identification (trigger=296683)
  42. GRB 071112C: Swift-BAT refined analysis
  43. GRB 071112C: Swift/UVOT observations
  44. GRB 071112C: Swift XRT refined analysis
  45. Swift UVOT upper limits of GRB071112B
  46. GRB 071112B: Swift-XRT preliminary analysis
  47. GRB 071112B, Swift-BAT partial refined analysis of the SHB
  48. Swift-BAT trigger 296491 is not a GRB
  49. GRB 071112C: TAROT Calern observatory optical observations
  50. Swift XRT follow-up observations of GRB071028B
  51. GRB 071112C: ROTSE-III Confirmation of Optical Counterpart
  52. GRB 071112B: ROTSE-III Rapid Optical Limits
  53. GRB 071112C: Swift detection of a burst with an optical counterpart
  54. GRB 071112B: Swift detection of a short hard burst
  55. GRB 071112: Swift detection of a possible burst
  56. VLA IInd observation of INTEGRAL burst GRB 071109
  57. Swift/UVOT initial analysis of GRB071109
  58. GRB 071109: further Swift-XRT analysis
  59. No radio detection at Swift-XRT position
  60. GRB 071109: Swift-XRT possible X-ray counterpart
  61. GRB 071104: Swift-XRT Team Refined Analysis
  62. GRB 071104: Possible Swift UVOT Afterglow Candidate
  63. GRB 071104: Swift-XRT position
  64. Swift XRT and UVOT observations of GRB071028B
  65. GRB 071101, Swift-BAT refined analysis
  66. GRB 071101: Swift-XRT Team refined analysis
  67. GRB 071101: TAROT Calern observatory optical observations
  68. GRB 071101: Swift XRT position
  69. GRB 071101: BOOTES-2 prompt optical observations
  70. GRB 071101: a nearby galaxy
  71. GRB 071101: Swift detection of a burst
  72. GRB 071031, Swift-BAT refined analysis
  73. GRB 071031: Swift/UVOT detection of afterglow
  74. GRB 071031: Swift-XRT Team refined analysis
  75. GRB 071031: Swift detection of a burst with an optical counterpart
  76. GRB 071028B Swift-BAT detection of a burst
  77. Swift UVOT upper limits to GRB071028
  78. GRB 071028: Swift-XRT Team refined analysis
  79. GRB 071028, Swift-BAT refined analysis
  80. GRB 071028: Swift detection of a burst
  81. GRB 071025: Kuiper Telescope Optical Observations
  82. GRB 071018: Revised BAT position
  83. GRB 071025A: RAPTOR Observations of Complex Early Optical Behavior
  84. GRB071021: MARGE Optical Limits
  85. GRB071020, optical upper limit
  86. GRB 071025 Milagro GeV/TeV Observations
  87. Swift UVOT upper limits
  88. GRB 071025: Swift-XRT Team refined analysis
  89. GRB 071025, Swift-BAT refined analysis
  90. GRB 071025: Early Super-LOTIS Observations
  91. GRB 071025: ROTSE-III Refined Analysis
  92. GRB 071025: Swift XRT refined position
  93. GRB 071025: ROTSE-III Detection of Optical Counterpart
  94. GRB 071025: Swift detection of a burst
  95. GRB 071020: BTA spectroscopy
  96. Possible radio detection of GRB 071021 with the VLA
  97. Radio detection of GRB 071020 with the VLA
  98. GRB 071021: optical and NIR observations
  99. GRB 071021, Swift-BAT refined analysis
  100. GRB 071021: Swift-XRT Team refined analysis

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