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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"

28051 results found.

  1. GRB 071001: Swift detection of a burst
  2. VLA observation of GRB 070923
  3. GRB 070911, SMARTS optical/IR afterglow observations
  4. GRB 070925: Gemini South Imaging
  5. GRB070925: Swift-XRT Position
  6. GRB 070920B: ROTSE-III Early Optical Limits
  7. GRB 070925: a long GRB detected by INTEGRAL
  8. GRB 070923, Swift-BAT refined analysis
  9. GRB 070920B: XRT observations
  10. GRB 070917: Suzaku/WAM observation of the prompt emission
  11. GRB 070920B: TAROT La Silla observatory optical observations
  12. GRB 070920B, Swift-BAT refined analysis
  13. GRB 070911: Swift/BAT and Suzaku/WAM joint spectral analysis
  14. GRB 070920B: NOT optical observations
  15. GRB 070920, Swift-BAT refined analysis
  16. GRB 070920: TAROT Calern observatory optical observations
  17. GRB 070917: P60 Observations
  18. Konus-Wind observation of GRB 070917
  19. Swift Status and XRT Calibration Uncertainties
  20. GRB 070917: Swift-XRT observations
  21. GRB 070917: MITSuME Akeno Ic upper limit
  22. GRB 070917: R band observations
  23. GRB 070917, Swift-BAT refined analysis
  24. GRB 070911: Suzaku WAM observation of the prompt emission
  25. GRB 070913: Swift-XRT detection of the possible X-ray afterglow
  26. GRB 070809: The Swift evidence for the SHB nature of this burst
  27. GRB 070913: Afterglow candidate detected by TAROT La Silla observatory
  28. GRB 070913: Swift-BAT refined analysis
  29. GRB 070913: SMARTS optical/IR observations
  30. GRB 070913: TAROT La Silla observatory optical observations
  31. GRB 070911: PAIRITEL IR Observations
  32. GRB 070911: Swift XRT refined analysis
  33. GRB 070911, Swift-BAT refined analysis
  34. Intense burst from SGR 1806-20 detected on September 7
  35. GRB 070809: Confirmation of optical transient
  36. Candidate Orphan GRB Optical Transient in IC 4779
  37. Las Campanas observations of possible TAROT GRB transient near IC
  38. Orphan GRB candidate in IC 4779 at TAROT La Silla observatory
  39. GRB 070824 - Combined SuperAGILE/IPN Localization
  40. GRB 070731: Swift/UVOT Upper Limit
  41. GRB 070805: UVOT afterglow candidate retraction
  42. GRB 070810B : Faulkes Telescope South Observations
  43. GRB 070810A: Continued Keck Imaging
  44. GRB 070810B: Keck spectroscopy of possible host galaxies
  45. GRB070810B: Swift/UVOT Upper Limits
  46. GRB 070810B: XRT refined analysis
  47. GRB 070810B, Swift-BAT refined analysis
  48. Swift Trigger 287421: False trigger due to star tracker loss
  49. GRB 070810A: Swift-BAT refined analysis
  50. GRB 070810B: Xinglong TNT optical Upper Limit
  51. GRB070810B: Optical observations with KANATA
  52. A giant outburst from Cygnus X-1 detected by Konus-Wind and Suzaku-WAM
  53. GRB 070809: Swift/UVOT Upper Limits
  54. VLA upper limit on the short hard burst GRB 070729
  55. No radio detection in superAGILE burst 070724B
  56. GRB 070809: Keck Imaging
  57. GRB 070810: Swift-XRT Team Refined Analysis
  58. GRB 070809: Swift-XRT refined analysis
  59. GRB 070810: enhanced Swift-XRT position
  60. GRB 070810: Swift/UVOT Optical Counterpart
  61. GRB 070809, Swift-BAT refined analysis
  62. GRB 070808: Swift/UVOT upper limits
  63. GRB 070809: Swift detection of a short burst
  64. GRB 070808 : Faulkes Telescope South Observations
  65. GCN Swift XRT update position notices and enhanced position circulars
  66. GRB 070808: Swift XRT refined analysis
  67. GRB 070808, Swift-BAT refined analysis
  68. GRB 070808: OPTIMA-Burst optical upper limit
  69. GRB 070808: Xinglong TNT optical Upper Limit
  70. GRB070808: Optical observations with KANATA
  71. GRB070808 - SDSS Pre-Burst Observations
  72. GRB 070808: ROTSE-III Optical Limits
  73. GRB070805 XRT and UVOT afterglow candidate
  74. GRB070612A: Radio upper limit from GMRT
  75. GRB 070721B: correct afterglow position
  76. Swift/UVOT observations of GRB070805
  77. GRB 070805, Swift-BAT refined analysis
  78. UVOT observations of SAXJ1810.8-2609
  79. Swift detection of a outburst from SAX J1810.8-2609
  80. VLA non-detection of GRB 070721B
  81. GRB 070802: REM optical observations
  82. GRB 070802: Swift-XRT refined analysis
  83. GRB070802: Swift/UVOT upper limits
  84. GRB 070802, Swift-BAT refined analysis
  85. GRB 070802: V-band detection of the candidate afterglow
  86. GRB 070802: GROND J band candidate
  87. GRB 070731, Swift-BAT refined analysis
  88. Konus-A observation of GRB 070729
  89. Swift/UVOT detection of GRB070714B
  90. VLA upper limit on short hard burst GRB 070714B
  91. Intense burst from SGR 1806-20 detected on July 27
  92. GRB070729: Swift/UVOT upper limits
  93. GRB 070729: Swift-XRT refined analysis
  94. GRB 070729, Swift-BAT refined analysis
  95. GRB 070724B: P60 Observations
  96. GRB 070724B: Swift/UVOT Upper limits
  97. GRB 070724B: Swift-XRT afterglow likely candidate
  98. GRB 070721A: optical observations
  99. GRB 070724A: further VLT observations
  100. GRB 070724B: Suzaku WAM observation of the prompt emission

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