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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.

Advanced Search Examples (click to copy):

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

18485 results found.

  1. GRB 060121: OHP optical limits
  2. GRB 060124: TAROT optical limits
  3. GRB060124, optical observation
  4. GRB 060124: Optical Observations at Tautenburg
  5. GRB 060124: Swift-BAT detection of a burst
  6. GRB 060121: Liverpool Telescopes optical limits
  7. GRB 060121: candidate optical counterpart
  8. GRB 060121: Infrared Observations
  9. GRB 060121: optical observations
  10. GRB 060121: Optical imaging
  11. GRB060121 - SDSS pre-burst observations
  12. GRB 060121: A bright short/hard GRB localized by HETE-2 WXM
  13. HETE Alert 4006: MASTER promt optical limit
  14. GRB060117 - ATCA 3/6cm radio limits - correction
  15. GRB060117 - ATCA 3/6cm radio limits
  16. GRB 060116: possible I-J dropout
  17. GRB 060116: UKIRT IR Observations
  18. GRB 060117: FRAM optical afterglow candidate
  19. GRB 060117: nearby galaxy
  20. GRB 060116: VLT optical observations
  21. GRB 060116: IR Candidate Afterglow
  22. GRB 060116: Swift/UVOT upper limits
  23. GRB060115: REM observations
  24. GRB060116: Faulkes North observation
  25. GRB 060116: Swift-BAT detection of a burst
  26. GRB 060115: Swift/UVOT upper limits
  27. GRB 060114: REM observations
  28. GRB 060114: Swift/UVOT Observations
  29. GRB060115, optical observation
  30. GRB 060115: MITSuME optical afterglow candidate
  31. GRB 060115: Swift detection of a burst
  32. GRB060114, optical observation
  33. GRB060114: Faulkes North observation
  34. GRB 060108: IR observations of afterglow
  35. GRB 060108: Evidence for an XRT Position Offset
  36. GRB 060110: KAIT observations
  37. GRB 060111B: MITSuME detection of optical afterglow
  38. GRB 060111B: TAROT optical observation
  39. GRB060111A: RTT150 optical observations
  40. GRB060111B: RTT150, possible host galaxy
  41. GRB 060111(a): P60 Observations
  42. GRB 060111B: Gualba observatory limit
  43. GRB 060111B: Swift detection of a burst
  44. GRB 060111: Swift-BAT Refined Analysis
  45. GRB 060108: VLT K-band observations
  46. GRB 060111: TAROT optical observation
  47. GRB 060111: possible UVOT counterpart
  48. GRB 060111: Swift detection of a burst
  49. GRB 060110: Mitsume optical observations
  50. GRB 060108: z-band imaging from Gemini-North
  51. GRB 060110a: RAPTOR detection of early optical emission.
  52. GRB 060110: UKIRT K-band observations
  53. GRB 060110: IR Candidate Afterglow
  54. GRB060110, optical observation
  55. GRB 060110: Correction
  56. GRB 050110: IR Observations
  57. GRB 060109: Swift/UVOT upper limits
  58. GRB060109, optical observation
  59. GRB 060108: ISAS early observations and near IR upper limit
  60. GRB060108: P200 Ks Observations
  61. GRB 060108: early UKIRT K-band observations
  62. GRB 060109: Swift Detection of a long burst
  63. GRB 060108: VLT J-band observations
  64. GRB 060108: Mitsume optical observations
  65. GRB 060108: Swift/UVOT upper limits
  66. GRB 060105: quick look analysis of the Suzaku/XIS afterglow observation
  67. GRB060108: SDSS pre-burst observations
  68. GRB060108: Faulkes Telescope observation
  69. GRB060108, optical observation
  70. GRB060108: Swift detection of its 100th GRB
  71. GRB 060105: ISAS observations and near IR upper limit
  72. GRB 060105: Swift/UVOT upper limits
  73. GRB 060105: Mitsume optical observations
  74. GRB060105: Suzaku-XIS and -HXD observation plan
  75. GRB060105, optical observation
  76. GRB060105: Swift detection of a bright long burst
  77. Swift-BAT trigger 175653 is probably not a GRB
  78. GRB 051221B: Optical Observations with Kuiper 1.54m
  79. GRB 051227: optical observation
  80. GRB 051227: optical afterglow
  81. GRB 051227: Magellan r'-band Imaging/Astrometry
  82. GRB 051227: refined analysis of VLT images
  83. GRB 051227: P60 Observations
  84. GRB 051227: MDM Observation
  85. GRB 051227: R-band object in the XRT error circle
  86. GRB 051227: Refined analysis of the Swift-BAT burst
  87. GRB051227: SDSS pre-burst observations
  88. GRB 051227, optical observation
  89. GRB 051227: Swift detection of a burst
  90. GRB051117B: optical observation
  91. GRB 051221A: MDM Optical Observations
  92. GRB051016: analysis of the XMM-Newton observation
  93. GRB 051221B: TAROT optical limits
  94. Swift-BAT detection of a possible burst
  95. GRB 051221: Swift/UVOT upper limits
  96. GRB 051221: Improved astrometry of the IR counterpart
  97. GRB 051221: Swift detection of a bright short burst
  98. Swift detection of an RS CVn flare star
  99. GRB051211A: possible optical candidate
  100. GRB 051215: near-infrared observations

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