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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"

18430 results found.

  1. GRB 100906A: optical observations at Mt.Terskol
  2. GRB 100901A: optical observation in Maidanak, break confirmation
  3. GRB 100909A: Faulkes Telescope North afterglow candidate
  4. GRB 100909A: ROTSE-III Optical Limits
  5. GRB 100902A : Confirmation of afterglow and re-brightening with CFHT r’-band imaging
  6. GRB 100909A: Swift target of opportunity observation
  7. EVLA detection of radio afterglow of GRB100901A
  8. GRB 100901A: CrAO optical observations
  9. GRB100906A: R band observations
  10. Konus-Wind observation of GRB 100906A
  11. GRB 100906A: Fermi GBM observation
  12. GRB 100901A: TLS Detection at 5.5 days
  13. GRB 100906A: Swift-XRT refined analysis
  14. GRB 100906A: Enhanced Swift-XRT position
  15. GRB 100906A: Swift/UVOT Observations
  16. GRB 100906A: TLS Multicolor Observations
  17. GRB 100905A: Swift/UVOT Upper Limits
  18. GRB 100901A: ISON-NM optical observations
  19. GRB 100906A: Swift-BAT refined analysis
  20. GRB 100906A: MASTER preliminary polarization prompt light curve
  21. GRB 100906A : Faulkes Telescope North optical observations
  22. GRB 100906A: MASTER early OT observations
  23. GRB 100906A: Swift detection of a burst with an optical afterglow
  24. GRB 100905A: Swift-XRT refined analysis.
  25. GRB 100905A: Enhanced Swift-XRT position
  26. GRB 100905A: Swift-BAT refined analysis
  27. GRB100904A: BOOTES-3 Upper Limit
  28. GRB 100905A: MASTER Prompt Optical Observations
  29. GRB 100905A: Faulkes Telescope North observations
  30. GRB 100905A: Swift detection of a burst
  31. GRB 100904A: Swift-BAT refined analysis
  32. GRB 100904A: Swift detection of a burst
  33. GRB 100902A: Swift-BAT refined analysis
  34. GRB 100901A: optical observation at Mt.Terskol
  35. GRB 100901A: multicolor photometry at Mt.Terskol
  36. IPN Triangulation of the very bright GRB 100829A
  37. GRB 100901A: Lightbuckets Optical Observations
  38. GRB 100902A: 1.5m OSN I-band Upper Limits
  39. Tentative redshift of GRB100902A from Swift-XRT data
  40. GRB 100902A: Swift XRT refined analysis
  41. GRB 100902A: Swift/UVOT Upper Limits
  42. GRB 100902A: optical observation at Mt.Terskol
  43. GRB 100901A: optical observation at Mt.Terskol
  44. GRB 100902A: Enhanced Swift-XRT position
  45. GRB 100901A: TLS Observations: Break?
  46. GRB 100902A: MASTER Prompt Optical Observations
  47. GRB 100901A: ISON-NM optical observations
  48. GRB 100902A: MASTER Optical Early Limit
  49. GRB 100902A: Swift detection of a burst
  50. GRB 100901A: 1.5m OSN BVRI-band observations.
  51. GRB 100901A: ROTSE-III Detection
  52. Swift/UVOT Observations of GRB100901A
  53. GRB 100901A: Swift-XRT Team refined analysis
  54. GRB 100901A: Swift-BAT refined analysis
  55. GRB 100901A: optical observation at Mt.Terskol
  56. GRB 100901A: Enhanced Swift-XRT position
  57. GRB 100901A: optical observation at Mt.Terskol
  58. GRB 100901A: MASTER power low decay
  59. GRB 100901A: MASTER: the OT brightenning
  60. GRB 100901A: confirmation of the afterglow
  61. GRB 100901A: MASTER Optical Early Limits
  62. GRB 100901A: Faulkes Telescope North afterglow candidate
  63. GRB 100901A: Swift detection of a burst with an optical afterglow
  64. GRB 100823A: optical upper limit
  65. GRB 100814A: Maidanak optical observations
  66. GRB 100823A: optical observations
  67. GRB 100823A: MAXI/GSC detection
  68. GRB 100725B: Mondy optical upper limit
  69. GRB 100725B: Maidanak optical upper limit
  70. GRB 100823A: Swift/UVOT Evidence for Fading Afterglow Emission
  71. GRB100807A: R band observations
  72. GRB100823A : MOA optical observation
  73. GRB 100823A: Swift XRT refined analysis
  74. GRB 100823: 1.5m OSN I-band observations
  75. GRB 100823A: Swift/UVOT Upper Limits
  76. GRB 100823A: Swift-BAT refined analysis
  77. GRB 100823A: Enhanced Swift-XRT position
  78. GRB 100823A: Swift detection of a burst
  79. GRB 100814A: Suzaku WAM observation of the prompt emission
  80. GRB 100814A: ISON-NM optical observations
  81. EVLA radio afterglow detection of GRB 100814A
  82. GRB 100814A: optical observations
  83. Konus-Wind observation of GRB 100816A
  84. GRB 100816A: Fermi GBM observation
  85. Konus-Wind observation of GRB 100814A
  86. GRB 100816A: Gemini-N spectroscopy
  87. GRB 100816A: Swift UVOT Observations
  88. GRB100816A Swift-XRT refined analysis
  89. GRB 100816A: Swift-BAT spectral lag results
  90. GRB 100816A: 1.23m CAHA optical observations
  91. GRB 100816A, Swift-BAT refined analysis
  92. GRB 100816A: Enhanced Swift-XRT position
  93. GRB100814A - interesting UVOT lightcurve.
  94. GRB 100816A: TAROT Calern observatory optical detection
  95. GRB100816A: TNG optical afterglow confirmation.
  96. GRB 100816A: ROTSE-III Optical Limits
  97. GRB 100816A: Swift detection of a possibly short burst with optical afterglow
  98. Swift-BAT trigger 431756 is not a burst
  99. Swift/UVOT observations of GRB100814A - title correction to GCN 11097
  100. GRB 100814A: Fermi GBM observation

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