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GCN Circulars

GCN Circulars are rapid bulletins submitted by and distributed to the community. 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"

28125 results found.

  1. GRB 061210: Optical sources near XRT positions
  2. GRB 061210: Swift XRT analysis - Possible counterparts
  3. GRB 061210 : Faulkes North Telescope optical limit
  4. GRB 061214(?): Swift detection of a possible burst
  5. GRB 061210: Gemini/GMOS Observations
  6. GRB 061126: Radio Observations
  7. GRB061201, VLT optical decay: correction
  8. GRB 061210: Swift-BAT detection of a short burst
  9. Optical Afterglow observations of GRB 061126
  10. GRB061126: optical observations
  11. GRB 060926: MASTER: discovery of the optical flare
  12. GRB061126: update on the Swift-XRT afterglow light curve
  13. GRB 061201: UVOT Observations of a Fading Optical Afterglow
  14. GRB 061201: VLT optical decay
  15. GRB 061201: SOAR Confirmation of Candidate Afterglow
  16. GRB 061202: Swift XRT refined analysis
  17. GRB061202: optical/NIR observations with REM
  18. GRB061202: Swift/UVOT Upper Limits
  19. GRB 061202: Swift detection of a burst
  20. GRB 061201: Swift XRT Team refined analysis
  21. GRB 061201: VLT optical observations
  22. GRB 061201: Initial UVOT Observations
  23. GRB 061201: Swift detection of a short hard burst
  24. GRB 061201: Coincidence with a Galaxy Cluster
  25. GRB 061122: GETS observation
  26. GRB 061121, SMARTS optical/IR observations
  27. GRB 061121: flattening of the decay
  28. INT+WFC observations of GRB 061126
  29. GRB 061126: Possible Jet Break
  30. GRB 061121: Second Epoch ATCA Radio Observations
  31. GRB 061126: RAPTOR Optical Detection During Gamma-Ray Emission
  32. Swift XRT on-board boresight update
  33. GRB 061121: ATCA & WSRT Radio Observations
  34. GRB061121: optical observations
  35. GRB 061126: Early Super-LOTIS Observations
  36. GRB 061126: optical observation
  37. GRB 061126: Tautenburg afterglow observations
  38. GRB061126: Optical afterglow observations from MIRO
  39. GRB061126: Optical afterglow observations from MIRO
  40. GRB 061126: Swift-XRT refined analysis
  41. GRB 061126: Swift/UVOT Observations
  42. GRB 061126: Early Detection of the IR Afterglow
  43. GRB 061126: Faulkes Telescope North Optical Observations
  44. GRB 061126: Swift/UVOT Afterglow Detection
  45. GRB 061126: XRT position
  46. GRB 061126: Swift detection of a burst
  47. GRB 061122: Confirmation of X-ray/Optical Afterglow
  48. GRB061121: optical observations
  49. GRB 061122: Candidate Optical Afterglow
  50. GRB 061121: Ep,i - Eiso correlation
  51. GRB 061121: MDM Optical Decay
  52. GRB061122: Swift/UVOT Optical Observations
  53. GRB 061121: ART detection in Ic
  54. GRB061121: P60 Observations
  55. Radio detection of GRB 061121
  56. GRB061122: Swift-XRT position
  57. GRB 061121 declared "Burst of Interest" by Swift team
  58. Swift-BAT trigger 239987 is not a GRB
  59. GRB 061121: Swift/UVOT Observations
  60. GRB 061121: Swift-XRT Team Refined Analysis
  61. GRB 061121: Optical observation at the KANATA 1.5m telescope
  62. GRB 061121: Faulkes Telescope North Optical Observation
  63. GRB061121: Spectroscopic Redshift
  64. GRB061121: Keck spectroscopic observations
  65. GRB 061121: Swift detection of a bright burst with an optical counterpart
  66. GRB 060605: NIR Observations
  67. GRB 050915B: optical afterglow
  68. GRB 060111B: Swift UVOT Refined Magnitudes
  69. GRB 061110A: refined R-band analysis
  70. GRB 061110B: NIR Observations
  71. Swift TOO observations of GRB061110A
  72. Swift/UVOT Upper Limits for GRB061110b
  73. Swift/UVOT Upper Limits for GRB061110a
  74. GRB 061110A - VLT tentative redshift
  75. GRB 061110B: Swift XRT refined analysis
  76. GRB 061110B: VLT redshift
  77. GRB 061110A: Swift XRT refined analysis
  78. GRB 061110B: Swift/XRT position
  79. GRB 061110B : Liverpool Telescope Optical Afterglow Detection
  80. GRB 061110B: Swift-UVOT Initial Observation
  81. GRB 061110B: Swift detection of a burst
  82. GRB 061110: NOT observations
  83. GRB 061110: Candidate confirmed
  84. GRB 061110 : Optical afterglow candidate
  85. GRB 061110: ROTSE-III Optical Limits
  86. GRB 061110: Swift detection of a burst
  87. GRB061110A - Optical Non-detection
  88. GRB 061109: Swift detection of a possible burst
  89. GRB061028: MAGIC telescope GeV observation
  90. GRB 061007: Third Epoch ATCA Radio Observations
  91. GRB061019: second epoch CrAO observations
  92. GRB 061028: Swift/XRT Astrometry Correction
  93. GRB 061102: Swift/UVOT Magnitude Upper Limits
  94. GRB 061102, XRT refined analysis
  95. GRB 061004: Further VLT/NTT observations
  96. GRB 061028: Optical R passband observations
  97. GRB 061102B: Swift detection of a possible burst
  98. GRB 061102: Swift detection of a burst
  99. GRB 061028: VLA Observation
  100. GRB 061004: Swift/XRT Astrometry Correction

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