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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').
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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.

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subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

19224 results found.

  1. GRB 070911, SMARTS optical/IR afterglow observations
  2. GRB 070925: Gemini South Imaging
  3. GRB 070920B: ROTSE-III Early Optical Limits
  4. Recent SGR1806-20 Activity
  5. GRB 070917: Suzaku/WAM observation of the prompt emission
  6. GRB 070920B: TAROT La Silla observatory optical observations
  7. GRB 070911: Swift/BAT and Suzaku/WAM joint spectral analysis
  8. GRB 070920B: NOT optical observations
  9. GRB 070920: TAROT Calern observatory optical observations
  10. SGR1806-20: Swift-BAT detection of enhanced activity
  11. GRB 070917: P60 Observations
  12. Swift Status and XRT Calibration Uncertainties
  13. GRB 070917: MITSuME Akeno Ic upper limit
  14. GRB 070917: R band observations
  15. GRB 070917, Swift-BAT refined analysis
  16. GRB 070917: Swift detection of a bright burst
  17. GRB 070911: Suzaku WAM observation of the prompt emission
  18. GRB 070913: Swift-XRT detection of the possible X-ray afterglow
  19. GRB 070913: SMARTS optical/IR observations
  20. GRB 070913: TAROT La Silla observatory optical observations
  21. GRB 070913: Swift detection of a burst
  22. GRB 070911: PAIRITEL IR Observations
  23. GRB 070911, Swift-BAT refined analysis
  24. Intense burst from SGR 1806-20 detected on September 7
  25. GRB 070809: Confirmation of optical transient
  26. Candidate Orphan GRB Optical Transient in IC 4779
  27. Las Campanas observations of possible TAROT GRB transient near IC
  28. Orphan GRB candidate in IC 4779 at TAROT La Silla observatory
  29. Konus-Wind observation of GRB 070824
  30. GRB 070824 - Combined SuperAGILE/IPN Localization
  31. Konus-Wind observation of very bright GRB 070821
  32. GRB 070731: Swift/UVOT Upper Limit
  33. GRB 070805: UVOT afterglow candidate retraction
  34. GRB 070810B : Faulkes Telescope South Observations
  35. GRB 070810A: Continued Keck Imaging
  36. GRB 070810B: Keck spectroscopy of possible host galaxies
  37. GRB070810B: Swift/UVOT Upper Limits
  38. GRB 070810B: Xinglong TNT optical Upper Limit
  39. GRB070810B: Optical observations with KANATA
  40. GRB 070809: Swift/UVOT Upper Limits
  41. VLA upper limit on the short hard burst GRB 070729
  42. No radio detection in superAGILE burst 070724B
  43. GRB 070809: Keck Imaging
  44. GRB 070810: enhanced Swift-XRT position
  45. GRB 070810: Swift/UVOT Optical Counterpart
  46. GRB 070808: Swift/UVOT upper limits
  47. GRB 070809: ROTSE-III Optical Limits
  48. GRB 070809: Swift detection of a short burst
  49. GRB 070808 : Faulkes Telescope South Observations
  50. GCN Swift XRT update position notices and enhanced position circulars
  51. GRB 070808: Swift XRT refined analysis
  52. GRB 070808: Xinglong TNT optical Upper Limit
  53. GRB070808: Optical observations with KANATA
  54. GRB070808 - SDSS Pre-Burst Observations
  55. GRB 070808: ROTSE-III Optical Limits
  56. GRB070805 XRT and UVOT afterglow candidate
  57. GRB070612A: Radio upper limit from GMRT
  58. Swift/UVOT observations of GRB070805
  59. GRB 070805: Swift detection of a burst
  60. UVOT observations of SAXJ1810.8-2609
  61. Swift detection of a outburst from SAX J1810.8-2609
  62. VLA non-detection of GRB 070721B
  63. GRB 070802: REM optical observations
  64. GRB 070802: Swift-XRT refined analysis
  65. GRB070802: Swift/UVOT upper limits
  66. GRB 070802, Swift-BAT refined analysis
  67. GRB 070802: V-band detection of the candidate afterglow
  68. GRB 070802: GROND J band candidate
  69. Swift/UVOT detection of GRB070714B
  70. VLA upper limit on short hard burst GRB 070714B
  71. Intense burst from SGR 1806-20 detected on July 27
  72. GRB070729: Swift/UVOT upper limits
  73. GRB 070729: Swift-XRT refined analysis
  74. GRB 070724B: P60 Observations
  75. GRB 070724B: Swift/UVOT Upper limits
  76. GRB 070721A: optical observations
  77. GRB 070724A: further VLT observations
  78. GRB 070724B: Suzaku WAM observation of the prompt emission
  79. Konus-Wind observation of GRB 070724B
  80. Four radio sources in Swift-XRT error box of GRB 070724
  81. GRB 070724: P60 and Gemini Observations
  82. GRB 060814 - Keck host detection and redshift
  83. Swift/UVOT refined analysis of GRB070724
  84. GRB 070724: Swift-XRT Team refined analysis
  85. GRB 070721B: further observations and analysis
  86. GRB 070724: Swift detection of a burst
  87. GRB 070714B: Keck observations
  88. Swift/UVOT Observations of GRB070721A
  89. GRB 070721B : Faulkes Telescope South observations
  90. GRB 070721A : Faulkes Telescope South optical limit
  91. GRB 070721A: Swift/XRT refined analysis
  92. GRB070721B: A bright UVOT candidate
  93. GRB 070714B : Suzaku WAM observation of the prompt emission
  94. GRB070714B: TNG NIR observations
  95. GRB 070714A: Swift/UVOT Upper limits
  96. GRB 070714B: Swift/UVOT Upper Limits
  97. GRB 070714B: confirmation of optical afterglow
  98. GRB 070616: No Evidence for I Band Afterglow
  99. GRB 070714A: Swift XRT refined analysis
  100. GRB070714B: Swift-XRT refined analysis

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