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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"

8476 results found.

  1. GRB 060218: spectroscopic observations
  2. GRB 060218: Likely an underluminous GRB
  3. GRB060218: Radio Afterglow Discovery
  4. GRB 060219: Swift-BAT detection of a weak burst
  5. Brightening of the Optical Counterpart of the Possible GRB 060218
  6. GRB 060218: MDM Observations
  7. GRB 060218: Pre-burst detection of a possible host galaxy
  8. Further UVOT Observations of the Candidate Optical Afterglow for GRB 060218
  9. GRB 060218: Swift-BAT detection of a possible burst
  10. GRB 060213: optical afterglow not confirmed
  11. Swift UVOT observations of GRB060213
  12. GRB 060213: optical afterglow candidate
  13. GRB060213: Swift XRT observations and possible afterglow candidate
  14. GRB060213: MASTER final result
  15. GRB060213:_MASTER_optical_observation
  16. GRB 050826: Optical Afterglow and Host Galaxy
  17. GRB 060210: Optical Observations
  18. GRB060211.7: MASTER_optical_observation under the snow
  19. GRB 060211B: Swift-BAT detection of a burst
  20. GRB 060211: Swift detection of a long burst
  21. GRB 060210: Refined analysis of the Swift-BAT burst
  22. GRB060210:Faulkes Telescope North Afterglow Confirmation
  23. GRB 060210: candidate afterglow
  24. GRB 060210: Swift detection of a burst
  25. GRB060210: Optical afterglow
  26. GRB060209A: MASTER optical observation
  27. GRB 060209(?): Swift-BAT detection of a possible burst
  28. GRB 060203: Swift/UVOT upper limits
  29. Retraction of orphan GRB afterglow candidate
  30. Orphan GRB Afterglow candidate
  31. GRB 060204A: ROSAT Pointing
  32. GRB060206: Liverpool Telescope observation
  33. GRB 060206: RAPTOR observations of afterglow candidate variability.
  34. GRB060204a: Swift XRT Detection of an Afterglow Candidate
  35. GRB060206: Swift-BAT detection of a burst
  36. GRB 060204b: Keck/LRIS Afterglow Confirmation
  37. GRB 060204C: Liverpool Telescopes optical limit
  38. GRB 060204C: Swift-BAT detection of a burst
  39. GRB060204B: Faulkes OT candidate
  40. GRB 060204B: Swift detection of a burst
  41. GRB 060203: P60 Confirmation of Optical Afterglow
  42. Possible GRB 060203: candidate optical counterpart
  43. GRB 060202: Gemini-N J, H, K_s observations
  44. GRB 060202: Optical Afterglow Candidate from Keck/LRIS
  45. GRB 060202: Swift/UVOT upper limits
  46. GRB060202: Faulkes North observation
  47. GRB 060202: Swift detection of a burst
  48. GRB 060130: Swift/XRT observation
  49. GRB 051211A: MDM Observations
  50. GRB050121b: optical observation
  51. GRB 060124: Confirmation of the Afterglow
  52. GRB 060124: XRT position
  53. GRB 060124: Optical Afterglow Candidate from Tautenburg
  54. GRB 060124: Optical Observations at Tautenburg
  55. GRB060124:MASTER optical observation
  56. GRB 060121: Liverpool Telescopes optical limits
  57. GRB 060121: candidate optical counterpart
  58. GRB060121: SARA Observations
  59. GRB060117 - ATCA 3/6cm radio limits - correction
  60. GRB060117 - ATCA 3/6cm radio limits
  61. GRB 060116: photometric redshift - the farthest GRB?
  62. GRB 060116: PROMPT Observations
  63. GRB 060117: FRAM refined analysis
  64. GRB 060117: FRAM optical afterglow candidate
  65. GRB 060117: nearby galaxy
  66. GRB 060116: VLT optical observations
  67. GRB 060116: IR Candidate Afterglow
  68. GRB060116: Faulkes North observation
  69. GRB 060116: Swift-BAT detection of a burst
  70. GRB 060115: OT photometry with MITSuME
  71. GRB 060115: Swift/UVOT upper limits
  72. GRB 060115: MITSuME optical afterglow candidate
  73. GRB 060115: Swift detection of a burst
  74. GRB060114: Faulkes North observation
  75. GRB 060108: IR observations of afterglow
  76. GRB060108: Faulkes North afterglow evidence
  77. GRB 060111A: refined UVOT anaysis
  78. GRB 060111B: MITSuME detection of optical afterglow
  79. GRB060111A: RTT150 optical observations
  80. GRB 060111B: Swift detection of a burst
  81. GRB060111.2:_MASTER optical limit
  82. GRB 060111: possible UVOT counterpart
  83. GRB 060111: Swift detection of a burst
  84. GRB 060110: Mitsume optical observations
  85. GRB 060110: Swift-BAT refined analysis
  86. GRB 060110: IR Candidate Afterglow
  87. GRB 060110: Super-LOTIS observations
  88. GRB 060110: Optical observation
  89. GRB 060110: Correction
  90. GRB 050110: IR Observations
  91. GRB 060110: Optical limit
  92. GRB 060110: Swift-BAT detection of a burst
  93. GRB 060109: Swift Detection of a long burst
  94. GRB060108: Faulkes Telescope observation
  95. GRB060108: Swift detection of its 100th GRB
  96. GRB 060105: Swift/UVOT upper limits
  97. GRB 060102 - no XRT afterglow
  98. GRB060105 : Kiso optical observation
  99. GRB060105: Swift detection of a bright long burst
  100. Swift-BAT trigger 175653 is not an astrophysical source

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