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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"

10376 results found.

  1. GRB 071122: ROTSE-III Optical Limits
  2. GRB071118 MITSuME OAO optical observation
  3. GRB 071117: Swift-XRT revised position
  4. Konus-Wind and Konus-A observations of GRB 071117
  5. Swift/UVOT upper limits for GRB 071117
  6. GRB 071117: Gemini Optical Afterglow Discovery
  7. GRB 071118, Swift-BAT refined analysis
  8. GRB 071117: TAROT La Silla observatory optical observations
  9. GRB 071118: Swift detection of a burst
  10. GRB 071117: Gemini Observations
  11. GRB 071117: Swift-XRT refined analysis
  12. GRB 071117: Swift/XRT position
  13. GRB 071112C: Optical and NIR data observed with KANATA
  14. GRB071112C: Errata of MITSuME Ic band photometry
  15. GRB 071112C: optical observation
  16. GRB071112C MITSuME Okayama Optical Observation
  17. GRB 071112B: Magellan i-band imaging
  18. GRB071112C Xinglong_TNT_and_EST_afterglow observations
  19. GRB 071112B: ROTSE-III Rapid Optical Limits
  20. GRB 071112: Swift detection of a possible burst
  21. GRB 071109: IBIS refined analysis
  22. GRB 071109: BOOTES-2 prompt optical observations
  23. GRB 071109: A long GRB detected by INTEGRAL
  24. GRB 071104: Gamma Ray Burst Localization by SuperAGILE
  25. GRB 071101, Swift-BAT refined analysis
  26. GRB0711101: Two new source from Xinglong TNT observation
  27. GRB 071020: MITSuME Akeno optical observations
  28. GRB 071028: Swift detection of a burst
  29. GRB 071025: Kuiper Telescope Optical Observations
  30. GRB 071018: Revised BAT position
  31. GRB071020, optical upper limit
  32. GRB 071025: Swift-XRT Team refined analysis
  33. GRB 060602A: host redshift
  34. GRB 071025: Early Super-LOTIS Observations
  35. Optical observations of GRB 071020
  36. GRB071021: MITSuME Okayama Optical Upper Limits
  37. GRB 071010B: Fading quickly
  38. Konus-Wind observation of GRB 071020
  39. GRB 071020A: IR Imaging with PAIRITEL
  40. GRB071010b: optical observations
  41. GRB 071018, Swift-BAT refined analysis
  42. GRB 071010B: Suzaku WAM observation of the prompt emission
  43. GRB 071013: Optical observations
  44. GRB071013: optical limit
  45. GRB 20071013: Xinglong TNT optical Upper Limit
  46. GRB 071010C Swift-BAT detection of a burst
  47. GRB 071011: MARGE Optical Limits
  48. GRB 071010B: Gemini Spectroscopic Observations
  49. Optical Observation: GRB 071010
  50. Optical observations: GRB 071010A
  51. Konus-Wind observation of GRB 071010B
  52. GRB071010B: Swift/XRT detection
  53. GRB 071010B, Swift-BAT refined analysis
  54. GRB071008: optical observations
  55. GRB 071010B: Swift detection of a burst
  56. GRB 071010, Swift-BAT refined analysis
  57. Konus-Wind observation of GRB 071006
  58. GRB071008: Swift-XRT observation
  59. GRB 071010: Keck Observations of the Afterglow
  60. GRB 071008: Swift detection of a burst
  61. GRB 070810B: further XRT analysis
  62. Konus-Wind observation of GRB 071003
  63. GRB 071003: Possible rebrightening
  64. GRB 071003: KAIT optical afterglow observations
  65. GRB 071001, Swift-BAT refined analysis
  66. Disregard the Swift-XRT Notices today
  67. GRB 070920B: ROTSE-III Early Optical Limits
  68. GRB 070925: a long GRB detected by INTEGRAL
  69. Recent SGR1806-20 Activity
  70. INTEGRAL ToO observations of SGR1806-20
  71. GRB 070920B, Swift-BAT refined analysis
  72. SGR1806-20: Swift-BAT detection of enhanced activity
  73. Konus-Wind observation of GRB 070917
  74. GRB 070917: KAIT optical limits
  75. GRB 070911: Suzaku WAM observation of the prompt emission
  76. GRB 070913: Swift detection of a burst
  77. IPN search for a GRB associated with TAROT transient on August 31
  78. Intense burst from SGR 1806-20 detected on September 7
  79. GRB 070809: Confirmation of optical transient
  80. Orphan GRB candidate in IC 4779 at TAROT La Silla observatory
  81. Konus-Wind observation of GRB 070824
  82. GRB 070824 - Combined SuperAGILE/IPN Localization
  83. Konus-Wind observation of very bright GRB 070821
  84. IPN Localization of GRB 070821 (long, very bright)
  85. GRB 070810B: Xinglong TNT optical Upper Limit
  86. GRB 070809: Swift/UVOT Upper Limits
  87. GRB 070810B: Swift detection of a short burst
  88. GRB 070810: Swift detection of a burst
  89. GRB 070809: ROTSE-III Optical Limits
  90. GRB 070808: Swift XRT refined analysis
  91. GRB 070808: ROTSE-III Optical Limits
  92. GRB070805 XRT and UVOT afterglow candidate
  93. GRB 070805: Swift XRT initial analysis.
  94. GRB 070802, Swift-BAT refined analysis
  95. GRB 070802: GROND J band candidate
  96. Konus-A observation of GRB 070729
  97. AGILE-ACS position for the SGR 1806-20 July 27 burst
  98. Intense burst from SGR 1806-20 detected on July 27
  99. Konus-Wind observation of GRB 070724B
  100. GRB 070724B: Analysis of AGILE gamma-ray data

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