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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.

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

3798 results found.

  1. GRB 060428B: Refined analysis of the Swift-BAT burst
  2. GRB 060428B: KAIT observations
  3. GRB060425:MASTER optical limit
  4. GRB060425:MASTER survey observations
  5. GRB 060425: IPN localization and KW spectrum of a short, hard burst
  6. GRB 060421: TTT Observations
  7. Konus-Wind observation of GRB 060418
  8. GRB 060322: Confirmation of Swift XRT afterglow
  9. GRB060211B: optical observation
  10. SGR 1900+14: Refined Swift-BAT analysis of the renewed activity
  11. GRB 060322: Refined analysis of the Swift-BAT burst
  12. GRB 060319: Swift detection of a burst
  13. GRB 060312: Refined analysis of the Swift-BAT burst
  14. GRB 060312: ROTSE-III Optical Limits
  15. GRB 060218/SN 2006aj: WIRO optical observations
  16. GRB 060213: IPN localization
  17. GRB 060211A: Further refined analysis of the Swift burst
  18. GRB060105: optical observations
  19. GRB 060211A: Partial refined analysis on the Swift-BAT burst
  20. GRB 050826: Optical Afterglow and Host Galaxy
  21. GRB 060211B: Swift/BAT refined analysis
  22. GRB060211.7: MASTER_optical_observation under the snow
  23. GRB 060211B: Swift-BAT detection of a burst
  24. GRB 060206: Swift/UVOT Observations
  25. GRB 060206: Swift-BAT refined analysis
  26. GRB 060204B: Swift-BAT refined analysis
  27. GRB 060204B: Swift detection of a burst
  28. GRB 060202: PROMPT Observations
  29. GRB060202, optical observation
  30. GRB060114, optical observation
  31. GRB060110, optical observation
  32. GRB060108, optical observation
  33. GRB 051227: Refined analysis of the Swift-BAT burst
  34. GRB 051221A: RAPTOR Fading Counterpart Constraint
  35. GRB 051221: IR Observations at GRB+1hr
  36. GRB 051210: Magellan Imaging
  37. GRB 051111: ROTSE-III Analysis of Prompt Counterpart
  38. GRB051109A: further steepening in the X-ray light curve
  39. GRB051021: A GRB Localized by HETE
  40. GRB 051008, optical observations
  41. Swift-BAT trigger 158700 is a probable Cosmic Ray Shower Event
  42. GRB050922C - Swift UVOT preliminary analysis
  43. GRB 050922C: Swift detection of a bright burst
  44. GRB 050922B: ROTSE-III Optical Limits
  45. WIRO observations in I of GRB 050908
  46. GRB050908 : Swift-XRT refined analysis
  47. GRB 050908: Swift-BAT refined analysis
  48. GRB 050908: Optical observations
  49. GRB 050908 : Swift XRT position
  50. GRB 050908: KAIT observations
  51. GRB 050908: Optical Observations
  52. GRB 050904: Swift/UVOT observations
  53. GRB050827: Swift-BAT detection of a burst
  54. GRB 050826: Optical Candidate
  55. GRB050817: Negative Optical Observations
  56. GRB 050814: Swift XRT Afterglow Localization
  57. GRB 050814: Swift detection of a burst
  58. GRB 050813: Swift-BAT refined analysis
  59. GRB 050813: Swift XRT afterglow localization
  60. GRB050807(=H3889): An X-Ray Rich GRB Localized by HETE
  61. GRB 050802: early Swift XRT analysis results
  62. GRB 050730, corrected photometry and break?
  63. GRB050801: Swift-BAT detection of a burst
  64. GRB 050730, spectra and optical photometry
  65. H3800 and H3801 on 2005 June 11: two bursts from SGR1806-20 localized by HETE
  66. GRB 050603: Afterglow Identification from LCO
  67. Swift/BAT Detection of GRB050603
  68. GRB050528, XRT observations
  69. GRB050504: Ashra-P2/3 monitor and Ashra-AFT response
  70. GRB 050505: early time observations
  71. GRB 050502 - A long GRB detected with INTEGRAL
  72. GRB 050416,optical observation
  73. GRB050412: P60 Observations
  74. GRB 050408: Optical limit
  75. GRB 050410, optical observations
  76. GRB 050408, optical observations
  77. GRB050401: ROTSE-III Detection of Prompt Optical Counterpart
  78. GRB050331: No Afterglow Detected
  79. GRB 050331: Swift XRT Position
  80. GRB050223: analysis of the XMM-Newton observation
  81. GRB 050219b: candidate NIR afterglow
  82. GRB050223 XMM-Newton observation
  83. GRB 050223: Swift XRT Position
  84. GRB050219b: CORRECTION to time of UVOT observations
  85. GRB050219b: No Swift UVOT Detection of Afterglow Emission
  86. GRB 050219b: CORRECTION to refined XRT position
  87. GRB 050219b: Optical and near-IR observations from LCO
  88. GRB050219b: No Swift UVOT Detection of Afterglow Emission
  89. GRB 050219b: Refined XRT position
  90. GRB 050219b: CORRECTION: Swift XRT Position
  91. GRB 050219b: Swift XRT Position
  92. GRB 050209 Optical observations
  93. GRB 050209: Optical observation
  94. GRB 050123: KAIT observations
  95. Third epoch observations of SGR 1806-20 with VLA
  96. GRB041224: Swift-BAT detection of a soft burst
  97. GRB041219: Optical Afterglow Detection
  98. GRB 041006: GETS Optical Afterglow Observation
  99. GRB 041006 : optical follow-up observation at Lulin Observatory
  100. Bursts from SGR 1806-20: Preliminary INTEGRAL results

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