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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"

21770 results found.

  1. GRB 060110: MARGE observations
  2. GRB 060111(a): P60 Observations
  3. GRB 060111B: Gualba observatory limit
  4. GRB 060111B: ROTSE-III Detection of Optical Counterpart Flare
  5. GRB 060111B: Swift detection of a burst
  6. GRB 060108: VLT K-band observations
  7. GRB 060111: TAROT optical observation
  8. GRB060111 : XRT refined analysis
  9. GRB 060111: ROTSE-III Optical Limits
  10. GRB 060111: Swift detection of a burst
  11. GRB 060110: Mitsume optical observations
  12. GRB 060108: z-band imaging from Gemini-North
  13. GRB 060110a: RAPTOR detection of early optical emission.
  14. GRB 060110: UKIRT K-band observations
  15. GRB 060110: IR Candidate Afterglow
  16. GRB060110, optical observation
  17. GRB 060110: Super-LOTIS observations
  18. GRB 060110: Correction
  19. GRB 050110: IR Observations
  20. GRB 060110: Swift-BAT detection of a burst
  21. GRB 060109: Swift/UVOT upper limits
  22. GRB060109, optical observation
  23. GRB 060108: ISAS early observations and near IR upper limit
  24. GRB060108: P200 Ks Observations
  25. GRB 060108: early UKIRT K-band observations
  26. GRB 060109: Swift Detection of a long burst
  27. GRB 060108: VLT J-band observations
  28. GRB 060108: Mitsume optical observations
  29. GRB 060108: Swift/UVOT upper limits
  30. GRB 060105: quick look analysis of the Suzaku/XIS afterglow observation
  31. GRB060108: SDSS pre-burst observations
  32. GRB060108: Faulkes Telescope observation
  33. GRB060108, optical observation
  34. GRB 060108: Refined analysis of the Swift-BAT burst
  35. GRB060108: Swift detection of its 100th GRB
  36. GRB 060105: MDM Observation
  37. Konus-Wind observation of GRB 060105
  38. GRB 060105: ISAS observations and near IR upper limit
  39. GRB 060105: Swift/UVOT upper limits
  40. GRB 060105: Mitsume optical observations
  41. GRB 060105: BAT refined analysis
  42. GRB 060105: XRT refined analysis
  43. GRB060105: Suzaku-XIS and -HXD observation plan
  44. GRB060105, optical observation
  45. GRB060105: Swift detection of a bright long burst
  46. GRB 060102: MDM Observation
  47. Swift-BAT trigger 175653 is probably not a GRB
  48. GRB 051221B: Optical Observations with Kuiper 1.54m
  49. GRB 051227: optical observation
  50. GRB 051227: optical afterglow
  51. GRB 051227: Swift/UVOT Upper Limits (Possible U-band
  52. GRB 051227: Magellan r'-band Imaging/Astrometry
  53. GRB 051227: refined analysis of VLT images
  54. GRB 051227: P60 Observations
  55. GRB 051227: MDM Observation
  56. GRB 051227: R-band object in the XRT error circle
  57. GRB051227: SDSS pre-burst observations
  58. GRB 051227, optical observation
  59. GRB 051227: Swift detection of a burst
  60. GRB051117B: optical observation
  61. Konus-Wind observation of GRB 051221A
  62. GRB051221A: Suzaku WAM observation of the prompt emission
  63. GRB 051221A: MDM Optical Observations
  64. GRB 051221B: ROTSE-III Optical Limits
  65. GRB 051221B: TAROT optical limits
  66. GRB 051221A: RAPTOR Fading Counterpart Constraint
  67. GRB 051221B: BOOTES optical observations.
  68. Swift-BAT detection of a possible burst
  69. GRB 051221: Swift/UVOT upper limits
  70. GRB 051221: Improved astrometry of the IR counterpart
  71. GRB 051221: Swift detection of a bright short burst
  72. Swift-BAT discovery of hard x-ray transient SWIFT J1626.6-5156
  73. Swift detection of an RS CVn flare star
  74. GRB051211A: possible optical candidate
  75. GRB 051215: near-infrared observations
  76. GRB051215 - SDSS pre-burst observations
  77. GRB 051215: Swift detection of a possible burst
  78. GRB051105: optical observations
  79. GRB 051213: Swift-BAT refined analysis
  80. GRB 051211B, optical observation
  81. GRB 051211A: Swift/UVOT upper limits
  82. GRB 051211B: Swift/UVOT upper limits
  83. GRB 051211A,optical observation
  84. GRB051211B: Liverpool Telescope observation
  85. GRB051211b: P60 Observations
  86. GRB 051211A and GRB051211B: BOOTES simultaneous observations
  87. GRB 051210: Swift/UVOT upper limits
  88. GRB 051210: Magellan Imaging
  89. GRB 051211: TAROT optical limits
  90. GRB 051211B: a possible optical detection by TAROT
  91. GRB 051211:IAC80 optical observations
  92. GRB 051210: Optical imaging from Las Campanas
  93. GRB 051210: SALT detection limit
  94. GRB 051210: FRAM early limit
  95. GRB051210: Swift UVOT Observation
  96. GRB 051210: Swift detection of a burst
  97. An extraordinary long burst on December 3 from SGR1806-20
  98. Possible resuming of the SGR 1806-20 activity
  99. GRB051117b: No Swift/UVOT Detection
  100. GRB 051117A: Swift/UVOT Detection of an Afterglow

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